Liberty, Metaphor, and
Mechanism: "checks and balances" and the origins of modern
Professor of Intellectual History at Queen Mary, University of London
"So famous is the political theory of checks and balances, so well known to Americans, that he is a bold man who tries to say new things about it." Stanley Pargellis (1938)
1. Mechanical Systems. My subject is a topic which has been almost invisible to historians of political theory, the history of the concept of "checks and balances". The phrase is widely used in contemporary discussions of power and its regulation, and it is precisely because it has become so commonplace that historians and theorists have found it entirely unproblematic, treating it as if it was not a technical language (with all that that implies in the way of intellectual preconditions and hidden presuppositions) but a mere manner of expression. For Garry Wills, for example, it is, when used by the founding fathers, simply "an old concept borrowed from mixed government theory". There is a marked contrast here with the idea of the separation of powers, whose history has been carefully and intelligently studied. 
To study the phrase, one must make some straightforward distinctions. First, there is the history of the phrase itself, first used by John Adams (1735-1826, the second President of the United States) in his Defense of the Constitutions of the United States in 1787 (but "check and balance", as we shall see, had been used by the radical Whig John Toland as early as 1701, and "balance or check" by the Civil War republican Marchamont Nedham in 1654). Then there are the histories of the words out of which it is composed, for, I will argue, "check" and "balance" have separate histories in political theory. But the history of words and phrases is an empty thing if it is not a way of studying the history of concepts, and any study of the concept of checks and balances needs to include a wider family of words (such as "control", "clog", "counterpoise", and "equilibrium") which were often used to discuss the same or similar ideas. What all these words take for granted, I will maintain, is the idea that a political system can be usefully compared to a machine. Indeed the language I am concerned with here is entirely metaphorical. Nietzsche said that truth is "a mobile army of metaphors, metonyms, and anthropomorphisms," and the scientific revolution serves as a useful illustration of his claim: it is impossible to imagine what has been called the mechanization of the world picture without the metaphors of clock, machine, and automaton, without the metonymic (or perhaps rather synecdochic) distinction between primary and secondary qualities which lies at the heart of the mechanists' enterprise, and without the anthropomorphic conception of God as a clockmaker. And this new mechanical world picture provided in its turn a series of metaphors for talking about political constitutions.
This paper will thus demonstrate the need for a more careful attention to language in the history of political theory. Despite the fact that the Cambridge School have always stressed the importance of linguistic change, only a rather narrow range of terms, such as "state" and "liberty", have been studied historically; part of my purpose here is to show that words that apparently have nothing to do with politics, words such as "system" and "machine", can be central to the history of political theorizing. Indeed a study of the history of a phrase like "checks and balances" may give us a different understanding of its range of possible meanings. The Cambridge School have often claimed that the history of ideas can contribute something to normative moral and political philosophy. The conclusion of my argument is that contemporary references to "checks and balances" miss the most interesting of the ideas that have been embodied in the phrase.
I began with a complaint about the history of political theory, so my first obligation is to show that historians of political theory have failed to think about checks and balances. One example can stand for many. Few texts in the history of political thought have been more widely influential than John Pocock's 1977 introduction to James Harrington's Political Works. There he argues that classical republican theory (a term of art including Ancient Romans such as Cicero, Renaissance theorists such as Machiavelli, and English Civil War republicans such as Harrington) had, since Polybius in the second century BCE, been preoccupied with the idea of how to achieve political stability through balancing monarchy, aristocracy, and democracy. This problem became central to English-language political theory a few weeks before the start of the Civil War, when Charles I issued His Majesty's Answer to the Nineteen Propositions of Parliament, which stated that "There being three kinds of government among men, absolute monarchy, aristocracy and democracy, and all these having their particular conveniences and inconveniences, the experience and wisdom of your ancestors hath so molded this out of a mixture of these as to give to this kingdom (as far as human prudence can provide) the conveniences of all three, without the inconveniences of any one, as long as the balance hangs even between the three estates "  With these words Charles abandoned any claim to absolute rule and provoked what Pocock calls "a true revision of paradigms", a revision embodied in Philip Hunton's A Treatise of Monarchy (1643): "Hunton assumed that England was a mixed government, a balance of the independently subsisting forces of monarchy, aristocracy and democracy, just as described in the Answer to the Nineteen Propositions; and he further pointed out that in a true balance, each power checked, but none controlled, the other two, with the consequence that no human authority was above the balance or was competent to command once it had broken down." Hunton, we are told, "had employed the republican vocabulary" and it would seem natural to assume that that vocabulary was one of balances, checks, controls. It comes as something of a surprise to turn to Hunton and discover that Hunton uses none of these words, either in the Treatise or in its subsequent Vindication (1651). I think it is reasonable to complain that Pocock has read the concept of checks and balances back into the Treatise, where it is not (or is barely) to be found.
It is true that Hunton once addresses the idea of the balanced constitution, though in his own language:
in such a composed state [i.e. a monarchy mixed with aristocratic and democratic elements], if the monarch invade the power of the other two, or run in any course tending to the dissolving of the constituted frame, they ought to employ their power in this case to preserve the state from ruin; yea that is the very end and fundamental aim in constituting all mixed policies: not that they by crossing and jarring should hinder the public good; but that, if one exorbitate, the power of restraint and providing for the public safety should be in the rest: and the power is put into divers hands, that one should counterpoise and keep even the other: so that for such other estates, it is not only lawful to deny obedience and submission to illegal proceedings, as private men may, but it is their duty, and by the foundations of the government they are bound to prevent dissolution of the established frame. 
Restraint and counterpoise, one might argue, are terms strictly analogous to checks and balances. But restraint is a virtue as well as being a metaphor about limitations on freedom of action. Hunton's own summary of this passage, in the Vindication, is "My third argument for mixture was from its end, which was restraint from excess." "Excess" is clearly a normative concept - indeed, in an Aristotelian world, where virtue is defined as a mean, "excess" is by definition a vice. Hunton has no interest in pursuing the concept of a balance beyond this passing remark because he is interested in authority and right, public good and private duty. To think seriously about checks and balances one has to start thinking about political systems in value-free terms, and to see them, indeed, as systems which can usefully be compared with mechanical systems.
It would be surprising indeed if Hunton was interested in doing this because the vocabulary he would have needed would have been as much mechanical as republican. In 1648 we find the first reference to the science of mechanics; it is followed in 1662 by mechanism; and in 1673 the word machine is first used to mean an apparatus for applying mechanical power - engine had been the English translation for the Latin machina until then. Thomas Hobbes, for example, described a watch as a small engine. John Evelyn, the diarist, is credited with being the first to introduce into English another word with a related meaning, but with a Greek origin, automaton (1645). In all the early usages the standard example of a machine or automaton was a clock, and like clocks before them, machines and automata soon became powerful metaphors for thinking of God, thinking of God as a clockmaker and the universe as a giant clock: as early as 1587, in a translation of the leading French Protestant, Philippe de Mornay, we find the heart described as a divinely constructed clock.
The idea of a system of checks and balances implies an idea of a constitution as a mechanical system, and that implies an interest in mechanism. The earliest reference to a "political machine" that I have been able to find is in John Dryden's edition of Plutarch's Lives (1683), in the life of Lycurgus:
when he perceived that his laws had taken deep root in the minds of his countrymen, that custom had rendered them familiar and easy, that his commonwealth grew apace daily, and was able to go alone, he had such a calm joy and contentation of mind, as Plato somewhere tells us the Maker of the World had, when he had finished and set this great machine a moving, and found everything very good and exactly to answer his great Idea; so Lycurgus, taking an unspeakable pleasure in the contemplation of the greatness and beauty of his work, seeing every spring and particular of his new establishment in its due order and course, at last he conceived a vast thought to make it immortal too, and, as far as human forecast could reach, to deliver it down unchangeable to posterity.
Here machine translates the Greek word cosmos.
Within a few years such usages of the word were common. Here the key figures are John Trenchard, his friend Walter Moyle, and their associate John Toland, the three of whom played the central role in refashioning the republican intellectual tradition to justify opposition to William III's efforts to build a strong state, capable of withstanding attack by the France of Louis XIV. These radicals insisted that a professional army (particularly if kept up during peace time) was (as republicans had often claimed) a dangerous threat to political liberty. In An Argument Showing That A Standing Army Is Inconsistent With A Free Government (1697) Trenchard and Moyle say that their objective is "to put in motion this machine of our government, and to make the springs and wheels of it act naturally and perform their function." Soon afterwards, Trenchard, in his "incomparable preface" to his Short History of Standing Armies (1698), argues that "a government is a mere piece of clockwork, and having such springs and wheels, must act after such a manner: and there the art is to constitute it so that it must move to the public advantage." The secret is "to make the interest of the governors and the governed the same", "and then our government will act mechanically, and a rogue will as naturally be hanged as a clock strike twelve when the hour has come."  Moyle, writing An Essay on the Lacedaemonian Government in the same year, maintained that the best constitution provided "a proper distribution of power into several branches, in the whole composing as it were one great machine, and each grand branch was a check upon the other; so that not one of them could exceed its just bounds."  It is not a coincidence that Toland, who may even have collaborated with Trenchard and Moyle in writing the Argument, uses the phrase "check and balance" soon after. One of their critics was dismayed by the effectiveness of this new language: "Can you bear smiling at the simplicity of mankind, to find how many swallow your notions, because you talk so finely for liberty, a militia to defend it, and engineering in your studies?" (This, by the way, is more than twenty years earlier than the OED's first recorded use of "engineering" as a noun.)
In the light of my earlier reading of Hunton, you will expect me now to argue that this new mechanical language was linked to a rejection of moral categories in political analysis. And this is indeed the case. Trenchard, Moyle, and Toland, former Whigs, found themselves in alliance with former Tories, such as Harley, in attacking the new party of big government, the court Whigs. They were well aware that those in power shared (at least in theory) many of their principles. And they repeatedly acknowledged that William, as king, was both a legitimate ruler and a man to be trusted - it was essential that their attacks on his policies should have no hint of Jacobitism. But their claim was that good men would eventually be replaced by bad men (it was only a short step, but one they hesitated to take, to claim that power tends to corrupt, and turns good men into bad), and that in the long run what counts is not the quality of the men or the rectitude of their intentions, but the nature of the political system within which they operate. As Trenchard and Moyle put it, "let us flatter our selves as much as we please, what happened yesterday will come to pass again, and the same causes will produce the like effects in all ages."  Moyle, writing to a friend, adopted a more learned language: "Thus you see, as a good author expresses it, eadem fabula semper in mundo agitur, mutatis duntaxat personis; which agrees with what Thucydides says in his third book, eadem accidere, donec eadem hominum natura." The casuistical terms in which Hunton and his contemporaries had conducted their debates could thus be dismissed as irrelevant. Trenchard, writing years later as Cato, still dismissed the conventional preoccupation with virtue: "The experience of every age convinces us, that we must not judge of men by what they ought to do, but by what they will do." The task of the political analyst was not to judge moral right and wrong, but to follow the chain of causes at work within a political system.
I find it easiest, as you will have noticed, to describe the new political theory by employing the word "system". Harrington had written of "the system of the government" and "a system of politics", but he seems to have had no immediate successors. Samuel Butler, in 1729, was giving the word (which had previously meant little more than an aggregation or grouping) a tightened definition when he wrote "The body is a system or constitution: so is a tree: so is every machine."  Once the word was readily available in this new sense it was quickly re-employed in political theory: it appears a year later in the first definition of the modern idea of a constitution in its political sense, Bolingbroke's statement that "By constitution we mean, whenever we speak with propriety and exactness, that assemblage of laws, institutions, and customs, derived from certain fixed principles of reason, that compose the general system according to which the community hath agreed to be governed." Indeed he uses it over and over again. The constitution is "a noble and wise system, the essential parts of which are so proportioned, and so intimately connected, that a change in one begets a change in the whole." King and people are "parts of the same system, intimately joined and co-operating together, acting and acted upon, limiting and limited, controlling and controlled by one another."  But for the pioneers of the new way of thinking in the final years of the seventeenth century "system" was a word that was too imprecise to serve their purposes. The preferred word to convey the idea of an interacting system was, as in the quotation from Butler, "machine". "Machine" was not a metaphorical term which stood in place of a readily available alternative; at first it was the only available term to convey the idea of complex interaction.
Even when the idea of a system was well-established, the reference to machines remained almost obligatory because the idea of a system remained entangled in the idea of a machine. Thus Adam Smith writes, in the History of Astronomy (c. 1749) (astronomy had played a key role in reshaping the word "system" because of its use in phrases such as "the Copernican system"), "Systems in many respects resemble machines. A machine is a little system, created to perform, as well as to connect together, in reality, those different movements and effects which the artist has occasion for. A system is an imaginary machine invented to connect together in the fancy those different movements and effects which are already in reality performed."  Trenchard and Moyle would have had no difficulty recognising the implicit claim that governments are machines in Hume's rhetorical question in "Of Refinement in the Arts" (1752): "Can we expect, that a government will be well modeled by a people, who know not how to make a spinning-wheel, or to employ a loom to advantage?"  It was still entirely natural for John Adams, writing in 1765, to compare political constitutions at length with the constitution of the body and with machines such as clocks ("a combination of weights, wheels, and levers, calculated for a certain use and end") before concluding "government is a frame, a scheme, a system, a combination of powers for a certain end, namely, - the good of the whole community." Indeed Sir James Steuart's An Inquiry into the Principles of Political Oeconomy (1767) could, when discussing this topic at least, have been written at the end of the previous century:
It is of governments as of machines, the more they are simple, the more they are solid and lasting; the more they are artfully composed, the more they become useful; but the more apt they are to be out of order.
The Lacedaemonian form may be compared to the wedge, the most solid and compact of all the mechanical powers. Those of modern states to watches, which are continually going wrong; sometimes the spring is found too weak, at other times too strong for the machine: and when the wheels are not made according to a determinate proportion, by the able hands of a Graham, or a Julien Le Roy, they do no tally well with one another; then the machine stops, and if it be forced, some part gives way; and the workman's hand becomes necessary to set it right.
There would seem to be an obvious objection to this line of argument. Is not the concept of a political system, or something very like it, already present in Polybius? In the words of a mid-twentieth-century translation, Polybius held that Lycurgus, in reforming the constitution of Sparta, understood the perils of a simple constitution, and therefore:
Combined together all the excellencies and distinctive features of the best constitutions, that no part should become unduly predominate, and be perverted into its kindred vice; and that each power being checked by the others, no one part should turn the scale or decisively outbalance the others; but that by being accurately adjusted in exact equilibrium, the whole might remain long steady like a ship sailing close to the wind. 
There are two things that are disconcerting about this translation. In the first place, it brings together into the same sentence the words check and [out]balance. Here, though, it simply reflects the magnetic attraction of the modern phrase "checks and balances" - the early translations of Polybius that I have been able to consult do not use the word "check", but rather phrases such as "mutually acted upon by opposite powers" or "each separate power being still counteracted by the rest". Even more alarming is the phrase "like a ship sailing close to the wind." In the first place, Greek ships could not sail close to the wind, so this must be a mistranslation; in the second place a ship sailing close to the wind implies a complex balance of a number of different forces - wind, sails, ballast, rudder - so if Polybius thought in such terms his notion of equilibrium would imply some sort of complex machine, not the simplest form of a balance, that of two weights in a scale - the sort of balance that has been familiar for millennia.
In fact, Polybius thought only in terms of the simple balance. The passage about a ship remaining in equilibrium while in movement, which might seem to suggest otherwise, has provoked much debate and continues to puzzle scholars because it contains a word found nowhere else.  The best interpretation as far as the sense is concerned (I am not competent to comment on the technical problems presented by the Greek) is in a French translation of 1792, which assumes, quite properly, that Polybius is thinking of a galley: if only the rowers on the port side row the ship turns clockwise; if only those on the starboard side row it turns anti-clockwise; if both row together an equilibrium is established and it proceeds in a straight line. In other words Polybius is still thinking of a simple balance between two equal forces, not of some complex balance between multiple forces - not of what we would call a "system", which needs to have several interacting parts. The standard modern translation takes Polybius to be talking about loading the cargo in a ship so it remains in trim as it travels along - again a balance of two equal forces.  Moreover Polybius assumed that the balancing of forces would be the result of deliberate action, not the unintended consequence of an interactive process. Theorists such as Trenchard and Moyle were interested in the idea that a political system might be constructed so that it would generate outcomes (such as the public good) that none of the participants had intended to achieve.
Thus to describe Polybius as having the idea of a political system is to read systems analysis (itself an aspect of mechanistic thinking) back into a pre-technological culture. When he was first taken up in English the balance was only one, and not necessarily the preferred, metaphor for the imposition of due limits. Here is His Majesty's Answer again: " as long as the balance hangs even between the three states, and they run jointly on in their proper channel (begetting verdure and fertility in the meadows on both sides), and the overflowing of either on either side raise no deluge or inundation." The mixing of metaphors here is testimony to just how little work the idea of the balance was capable of doing before the rise of mechanistic philosophy.
I have chosen a plainly anachronistic translation of Polybius because I want to stress that Polybius is not a fixed quantity, but was bound to be read differently at different times. What has become for modern commentators the key passage of Polybius's Histories was not always read - it survives only in a fragment, and was omitted from those editions which reproduced only the complete books. The middle of the eighteenth century saw what has been called the "rediscovery" of Polybius, and I want to suggest that this was a rediscovery of this particular passage, and was linked to the intellectual revolution I am discussing.  Even when the passage was translated, its meaning was sometimes far from apparent - a translation of 1634 renders the passage incomprehensible by changing one letter, for instead of saying "Royalty should be restrained from arrogancy by fear of the people" it says, perhaps under the pressure of censorship, perhaps simply through carelessness, "Loyalty should be restrained."
Our own preoccupation with Polybius as the source of the idea of the mixed constitution and of checks and balances is, in any case, somewhat misleading. Adams, in his Defense of the Constitutions of the United States, placed great emphasis on Polybius, and the author of His Majesty's Answer also appears to have had Polybius in mind, but for generations of politicians the idea of the balanced constitution would have been familiar, not from an obscure passage in Polybius, but from a far more widely read passage in Plutarch's life of Lycurgus.  The significance of this passage has been overlooked, perhaps because modern translations do not use the word balance. Here is the sixteenth-century translation of North:
In this change of the state, many things were altered by Lycurgus, but this chiefest alteration was, his law of the erection of a senate, which he made to have a regal power and equal authority with the kings in matters of weight and importance, and was (as Plato saith) to be the healthful counterpoise of the whole body of the Commonweal. The other state before was ever wavering, sometime inclining to tyranny, when the kings were too mighty; and sometime to confusion, when the people would usurp authority. Lycurgus therefore placed between the Kings and the people, a Council of Senators, which was as a strong beam, that held both these extremes in an even balance, and gave sure footing and ground to either part to make strong the state of the Commonweal. For the 28 Senators (which made the whole body of the Senate) took sometime the King's part, when it was needful to pull down the fury of the people: and contrariwise, they held sometimes with the people against the Kings, to bridle their tyrannical government. 
There is still only one balance here, not a series of checks and balances, but it is worth noting that there are close analogues here to Hunton's language of counterpoise, restraint, and foundation, so we can reasonably suspect that it is Plutarch not Polybius that Hunton had in mind.
I have paused over Plutarch's life of Lycurgus partly because Moyle, writing in his Essay on the Lacedaemonian Government about Harrington's scheme of government, said "How nearly this is drawn from Lycurgus's institution you may read with pleasure in his Life writ by Plutarch." This is true to a far greater extent than modern commentators on Harrington have acknowledged. The agrarian; the ballot; rotation of office; the separation between proposing and resolving; the mixture of monarchy, aristocracy and democracy; the idea of a government so constituted that it is capable of surviving for ever: all were described by Plutarch and taken up by Harrington. It was ostensibly on the basis of Plutarch and Harrington (and perhaps also on the basis of a reading of Nedham) that Moyle developed an account of what we now call the separation of powers, an account which surely influenced both Bolingbroke, whose essays in The Craftsman (1730) followed soon after the first publication of Moyle's work (though written in 1698 it did not appear in print until 1727), and Montesquieu (who, like Moyle, writes of the distribution, not the distinction - Nedham's term - or separation of power(s) and who, like Moyle, uses a selective account of an existing constitution to describe the maximum amount of liberty possible within civil society). For our purposes Moyle's essay of 1698, not Hunton's Treatise of 1643, represents the birth of a new language and a new paradigm: he writes of checks, of controls, of the balance of power (although perhaps not in its modern meaning), of machinery. That new paradigm owed a great deal to Harrington's conceptions of political architecture and political anatomy, but its vocabulary was only in part Harrington's. Harrington had written of checks (in the context of providing political supervision of military commanders), and of the law controlling the Lucchese (in the context of a refutation of Hobbes's views on liberty), but he had made no mention of machines, and when Harrington had written of "the balance" he meant the stable state created by an overbalance, not an equilibrium. The traditional idea of a balanced constitution he dismissed as a mere wrestling match between kings, lords, and commons, and in order to avoid the hated term "balance" when talking of constitutional provisions he adapted the term "libration" to a novel use.
Harrington, as his description of the constitution of Oceana draws to a close, quotes Plutarch's account of how Lycurgus had admired his own work and aspired to make it permanent. For readers of Moyle's generation this passage evoked images of machines driven by springs; but Harrington still read it as North had read it, as an account of man imitating God in the construction of an order comparable to that of the heavens: "he conceived such a delight within him, as God is described by Plato to have done when he had finished the creation of the world, and saw his own orbs move below him: for in the art of man (being the imitation of nature, which is the art of God) there is nothing so like the first call of beautiful order out of chaos and confusion as the architecture of a well-ordered commonwealth."  It is this step from the classical art of political architecture to the modern science of political engineering - which Trenchard called "the art of political mechanism" - that is marked by the new language of checks and balances. It is true that both Nedham and Harrington saw the frequent election of representatives as a key process in politics, which Nedham described as "revolution" and Harrington as "rotation", but the whole point of this movement, like the movement of the heavens was that it kept bringing the political system back to its original starting point, a conformity of interests between government and governed: which is why Harrington can mix astronomical and architectural metaphors in a single sentence. The new emphasis on mechanism, by contrast, made it possible for the first time to think about the political process in non-cyclical terms. For later theorists of constitutional machinery the importance of Polybius and Plutarch, of Nedham and Harrington was that they provided apparent precedents for what was in fact a new way of thinking.
Moyle, tracing the idea of the distribution of power back to Lycurgus, was effectively denying the modernity of the new political theory and the institutions it described. A much more subtle view is implicit in Montesquieu's Spirit of the Laws (1748). There Montesquieu writes of moderate governments as requiring the balancing of powers one against another. But mere moderation provides no guarantee of constitutional liberty, which exists only where there is a proper separation of powers. Only in England had the separation of legislature, executive, and judiciary (in the English case the "judge" in criminal cases being the jury) come properly into existence, and thus a constitution in which the separate powers provided adequate checks upon each other, and political liberty is consequently guaranteed, was evidently a modern invention.  However Montesquieu's account of the English constitution was theoretical rather than historical. Nowhere does he give any indication that he grasped that both the division of powers he so admired and the mechanical language he employed to describe their relationship to each other was scarcely older than he was. (He was born in 1689.)
2. Checks and Balances. "Checks and balances" is a phrase now widely employed to describe due process in decision making, and has a more precise meaning in descriptions of political constitutions where power is used to check power, of which the American constitution is the paradigmatic example. Nedham had written of a "balance or check" in 1654; Toland had used the phrase "check and balance" in 1701; and Gouverneur Morris had implied a plural form in 1776, writing of "every check and balance", but the phrase we now use was first used early in 1787 by John Adams in the opening pages of his Defense of the Constitutions of the United States, a work which defended the constitutions of the states and of the continental congress, for it was published a few months before the Convention proposed a new constitution for the federal republic. In that same year Noah Webster used the phrase "checks and balance"; and "balances and checks" was to appear in The Federalist that winter. Others quickly took up Adams's terminology: Jonathan Smith, for example, addressing the Massachusetts ratification convention, represented himself as "a plain man and get my living by the plough. I am not used to speaking in public, but I beg you[r] leave to say a few words to my brother ploughjoggers in this house." His few words were about "checks and balances."
It is time now to ask some straightforward, even obvious, questions. What are checks? What are balances? What exactly is being checked or balanced? And why do we need both checks and balances? At first, when I began to puzzle over the history of this phrase, my assumption was that the balance was the balance-wheel of a clock, that a check might be an escapement mechanism, and that "checks and balances" was a metaphor drawn from clockwork. But this is not the case, and the pre-history of the phrase proves peculiarly complex; my own efforts here are bound to require correction and modification.
Of the two terms, checks and balances, balance is the older, the one used (if I may so put it, for on this all the translators agree) by Polybius. According to seventeenth-century mechanics, the balance was the first of the six simple forces - the others being the lever, the wedge, the screw, the wheel and the pulley. (Of these, the most commonly used as a political metaphor, after the balance, was the screw, as in the following quotation from "A Maryland Farmer", "The aristocracy, who move by system and design, and always under the colorable pretext of securing property, act, as has been frequently said, like the screw in mechanics, always gaining, holding fast what it gains, and never losing."  Harrington had compared his principle of rotation to the working of a screw or a vice.) Whatever advances may have been made in the theory of the balance in the seventeenth century, there was nothing new about balances as such.
It is the idea of a balance between two forces that interested those who read Polybius and Plutarch before the eighteenth century. Thus Contarini (1543), as presented in a translation of 1599, praises Venice as embodying the Polybian ideal: "This only city retaineth a princely sovereignty, a government of the nobility, and a popular authority, so that the forms of all seem to be equally balanced, as it were with a pair of weights."  After The King's Answer the idea of the balance seems to have ceased to be of any significance in English political debate until it was reintroduced by Trenchard and Moyle in An Argument Showing that a Standing Army is Inconsistent with a Free Government (October 1697). The term then runs throughout the political debates of the next few years. Of the texts of this period the one that was best known in later years was Jonathan Swift's A Discourse of the Contests and Dissentions between the Nobles and Commons in Athens and Rome (1701), if only because Swift was so frequently reprinted (he was quoted at length by John Adams in 1787, and had been paraphrased by Benjamin Lincoln in 1785). Swift, who is writing a satire on contemporary politics under the guise of ancient history, opens with a discussion of the "balance of power", a phrase which first appears in English in 1579, in a translation of Guicciardini, and whose usage is said to have become common after the Treaty of Utrecht in 1713. In fact it had already become commonplace during the standing army debate of 1697-1701, being used sometimes in the Harringtonian sense of an overbalance (as in Moyle's "from modern politics we have been taught the name of the balance of power, but it was ancient prudence taught us the thing"), but sometimes also in the modern sense of an equilibrium or near-equilibrium, as when an anonymous critic of Trenchard and Moyle writes of "keeping the balance of power in a due libration, turning it sometimes one way, and sometimes another, according to present emergencies". The same idea of an equilibrium was commonplace during these years in discussions of "the balance of Europe". Here is Swift:
The true meaning of a balance of power, either without or within a state, is best conceived by considering what the nature of balance is. It supposes three things. First the part which is held, together with the hand that holds; and then the two scales, with whatever is weighed therein. Now consider several states in a neighborhood. In order to preserve peace between these states, it is necessary they should be formed into a balance, whereof one or more are to be directors, who are to divide the rest into equal scales, and upon occasions remove from one into the other, or else fall with their own weight upon the lightest. So in a state within itself, the balance must be held by a third hand, who is to deal the remaining power with utmost exactness into the several scales. Now it is not necessary that the power should be equally divided between these three; for the balance may be held by the weakest, who by his address and conduct, removing from either scale and adding of his own, may keep the scales duly poised.
Two things are very noticeable about this passage - the first is the assumption that a balance must always be a balance between two forces, so that if there are three powers they must re-divide themselves into two; the second is the conviction that maintaining a balance requires skill, a conscious analysis of the forces at work. One thinks of Halifax's Character of a Trimmer (1682) - the art of politics consists in knowing when to change sides, to trim the ship of state in order to restore the balance. This way of thinking implicitly likens the constitutional tension between three different institutions (king, lords, commons) to the task of building a coalition of parties within a single chamber. As Montesquieu put it (sliding, as eighteenth-century commentators could not help but do, between the static notion of constitutional equilibrium, and the dynamic notion of coalition formation), the three powers of King, Lords, and Commons "should form an equilibrium or a stasis. But since, in the necessary course of events, they are obliged to act, they will be obliged to act in concert."  It was natural for John Adams, in his influential "Thoughts on Government" of 1776, to assume that to "hold the balance" was synonymous with to "mediate." But it was also obvious that the struggle between two parties might easily degenerate into what Harrington had called a wrestling match. Usbek, in Montesquieu's Persian Letters (1721), maintains that "Monarchy is a state of tension, which always degenerates into despotism or republicanism. Power can never be divided equally between prince and people: it is too difficult to keep the balance. The power must necessarily decrease on one side and increase on the other, but usually the ruler is at an advantage, being in control of the armed forces."
How to escape from this bipolar model, with its associated stress on compromise, craft, and cunning, and its evident risk of instability? Bolingbroke in The Craftsman (in a passage, published in 1730, which is sometimes said to be a source for Montesquieu's doctrine of the separation of powers) distinguished sharply between the dependency of different parts of the government and their independency. In doing so he is discussing checks and the balance, but he uses the word balance coupled with the verb "control": Moyle had followed Nedham in employing the noun "control" in a political context, using it as synonymous with checks.
The constitutional dependency, as I have called it for distinction's sake, consists in this, that the proceedings of each part of the government, when they come forth into action and affect the whole, are liable to be examined and controlled by the other parts. The independency pleaded for consists in this, that the resolutions of each part, which direct these proceedings, be taken independently and without any influence, direct or indirect, on the others. Without the first, each part would be at liberty to attempt destroying the balance by usurping or abusing power; but without the last there can be no balance at all.
What was new about this was that it replaced the idea that there must in the end be only two forces in balance with the claim that the three forces must remain independent. A similar view is expressed by Blackstone in his Commentaries (1765), only he avoids the word "balance", with its suggestion of stasis. Like Bolingbroke, he starts with a mutual power of veto, and then moves on to the interaction of forces, which he deftly reinterprets as a dynamic process:
In the legislature, the people are a check upon the nobility, and the nobility a check upon the people while the king is a check upon both. And this very executive power is again checked and kept within due bounds by the two houses Thus every branch of our civil polity supports and is supported, regulates and is regulated, by the rest; for the two houses naturally drawing in two directions of opposite interest, and the prerogative in another still different from them both, they mutually keep each other from exceeding their proper limits Like three distinct powers in mechanics, they [people, nobility, executive] jointly impel the machine of government in a direction different from what either, acting by itself, would have done; but at the same time, in a direction partaking of each, and formed out of all: a direction which constitutes the true line of the liberty and happiness of the community
it is appropriate to think, here, if not when reading Polybius, of a ship sailing close to the wind, or (to take the hypothesis of Edward Spelman, in a note to his 1743 translation of Polybius), of a ship which is being rowed and at the same time carried by both the wind and the tide, for we really do have more than two independent forces at work.
Anyone who compares these two passages with the passage I earlier quoted from Swift must recognize that they are talking about different processes. Swift expects the resolutions of one part to influence at least one of the others, for otherwise it will be impossible to bring the scales into balance. Bolingbroke believes that if the different parts pay attention to each other they will necessarily become unbalanced, and Blackstone writes as if each could act independently of the others. A similar argument is made by John Adams in 1787. He maintains that any balance of two weights will be unstable (the whole point of a pair of scales is that the slightest alteration in the weights tips the balance) or tippy, and that three equal and independent weights are needed for stability.
All this would be incomprehensible if the only notion of equilibrium that existed in the eighteenth century was that of a scale in balance. In fact eighteenth-century textbooks on mechanics dealt carefully with the idea of an equilibrium between three independent weights, and we have, for example, Adams's notes on lectures he attended which dealt with this topic. Adams seems to have thought that a three-way balance was inherently more stable than a two-way balance: a mistake perhaps derived from the fact that the experimental apparatus employed in the schoolrooms to illustrate such a system was much less sensitive than a fulcrum balance, for it involved a pulley for each weight, so that movement would only take place when the friction of all the pulleys had been overcome.
There is a second issue here: need the weights be not only independent but also equal? Bernard Manin, who is one of the few people to have discussed political theories of balance with any care, believes that eighteenth-century theorists always believed that a balance required equal weights, and both Adams and his critics, when talking about the tripartite balance, write as if this were the case. But it would be very strange if everyone made this mistake. We have already seen Swift insisting that "it is not necessary that the power should be equally divided" between the three forces, and the three-way balance would scarcely have been an improvement on the bipolar balance if it had involved the introduction of a new principle of equality. In fact eighteenth-century textbooks showed how to balance three unequal weights in an equal-arm three-way balance by adjusting the angles between the arms.
It is easy to show that not all theorists of multiple balances presumed that the weights must be equal in balances involving three or more forces. This is apparent in Jean Louis de Lolme's Constitution of England (first published in French in 1771, and in English in 1775).  De Lolme argues that the legislature naturally outweighs the executive, with the resulting requirement that the weight of the legislature must be divided and dispersed, and the weight of the executive concentrated if a balance is to be achieved. Thus according to de Lolme one of the peculiarities of the English constitution is "its having thrown into one place the whole mass, if I may use the expression, of the executive power", which enables the royal authority to act as a counterpoise to the power of the people. Even so, the two powers are not as a result equal, for it is right that the power of the executive should be, in actuality if not appearance, the lesser of the two. But the legislative power, if it is not to be excessive, must be limited, and this can only be achieved by dividing it: "the same kind of impossibility is found to fix the legislative power when it is one, which Archimedes objected against his moving the earth" - a rare appeal, one might add, to the principle, if not of the lever, then at least of the fulcrum. Meanwhile, the people as a whole, as a body outside the constitutional system of powers, "at every instant have it in their power to strike the decisive blow which is to level everything", although they are only truly free when they have no need to exercise this unrestrained power. Thus for de Lolme the English constitution consists of a number of independent, separate, and unequal powers (including a judicial power consisting not only of an independent judiciary but also of juries who are judge of law as well as fact) whose "reciprocal actions and reactions produce the freedom of the constitution, which is no more than an equilibrium between the ruling powers of the state."  The key to establishing this equilibrium is weakening the legislature and strengthening the executive - the exact opposite of the policies advocated by Trenchard and Moyle.
So, too, for James Madison (who was to become President in 1809 and who had played the key role in the constitutional convention of 1787) and Alexander Hamilton (the leading advocate for the construction of a strong American state), the authors (with John Jay) of The Federalist (1787-8). Madison and Hamilton believed that since 1776 America had had plenty of experience of overpowerful legislatures). "It is against the enterprising ambition of [the legislature] that the people ought to indulge all their jealousy and exhaust all their precautions." "As the weight of the legislative authority requires that it should be thus divided, the weakness of the executive may require, on the other hand, that it should be fortified." The result of this division and fortification is not a balance of equal powers, for the executive is still the "weaker department", and the legislative authority contains within itself a "weaker branch" and a "stronger branch." It is these theorists of politics as the balancing of unequal forces who pioneered what is, I think, the most important and least recognized aspect of the theory of checks and balances, and we will return to them shortly, adducing further evidence that there is a close parallel between their arguments. So far we have seen that by the mid-eighteenth century there were two conflicting ways of thinking about a balance of powers, one (Swift's notion) which stressed the formation of alliances between two powers in order to balance a third, and the other (Bolingbroke's notion, derived in all probability from Moyle) which stressed the independency of the powers.
We turn now to the word check. No one seems to have asked when the word "check" is first used in a political context. It makes a couple of appearances in Nedham's A True State of the Case of the Commonwealth in 1654. It is probably as a result of Cromwell's reading of Nedham that we find him reported as saying to the army officers on 27 February 1657 that Parliament was in "need of a check or balancing power (meaning the House of Lords or a House so constituted)" to protect the rights of individuals, particularly in matters of religion. But I have not noticed the word "check" anywhere else until the upsurge in radical publication which followed the lapse of the Licensing Act in 1695: we have already seen it used by Moyle in 1698 - indeed he uses it repeatedly - and it was used in the same year by Trenchard, by Moyle's friend Hammond, and by Shaftesbury and Toland, the likely authors of The Danger of Mercenary Parliaments, who write of "a check and curb". In this last example we see it linked to what was presumably an earlier vocabulary, in which power was to be bridled (a word we have encountered in North's translation of Plutarch) and curbed. One of the attractions of the word "check" was that it could be used both in a mechanical context and in the context of a human action of surveillance or supervision. We often find it paired with control, which is similarly ambiguous, as in the following passage of Moyle's: "You may observe in every government that when the executive power is transferred to the legislative, there is no control, nor can there be any check upon them; the people in such a case must suffer without redress, they have no resource; because they are oppressed by their own representatives." But there are various types of check or control, and it is worth distinguishing them.
The obvious meaning of "check" was that of preventing an action, or exercising a veto: this was its original meaning in Nedham. In 1730, for example, we find James Pitt claiming that the three powers of the government "have a negative on each other" - the Commons being able to exercise a veto over the executive by refusing supply, or in Madison's phrase, employing "the engine of a money bill." Montesquieu, writing in French, talks about each power being able to empêche, arrête, or veto the other, and from him there derived a lengthy tradition which assumed that the executive must be able to exercise a veto over the legislature (although in eighteenth-century English constitutional practice this veto had in fact virtually ceased to exist: Jean Louis de Lolme could find no case of the king exercising his veto after 1692). 
But to check might also mean, in Bolingbroke's language, to examine and control. According to the OED, the first use of the word responsibility is in Hamilton and Madison's Federalist (1787).  In fact the word can be traced back to 1766, and was in frequent use in late eighteenth-century English in the context of discussions of ministerial responsibility. (It is one of the more remarkable examples of the power of metaphor that the nineteenth-century notion of moral responsibility has its origin in this notion of ministerial responsibility.)  But the idea, if not the word, goes back before then. The first example the OED gives for the use of responsible to mean "accountable" is in Prynne's Sovereign Power of Parliaments of 1643, where it is asserted that kings are responsible to their kingdoms or parliaments; and this was later extended into a clear doctrine of ministerial responsibility under another name. Thus Trenchard writes in 1698, "The law has always been very tender of the person of the king, and therefore has disposed the executive part of the government in such proper channels, that whatsoever lesser excesses are committed, they are not imputed to him, but his ministers are accountable for them" (although he goes on to complain that in practice this principle of accountability is easily evaded).  I am not sure when accountability was first described as a check, but it may well have been during the debates on impeachment of 1697/8. Certainly it is in this sense that the philosopher and historian David Hume wrote (in 1752) of the "particular checks and controls provided by the constitution", checks which make it in the interest of bad men to act for the public good: he is discussing the problem of how a government is to control its administration. For Blackstone too it is impeachment which serves as a check on the executive. So important might this idea of accountability seem that it was capable of swallowing up any other concept of checks and balances. According to the OED the first use of the word accountability was in The History of Vermont in 1794, in a reference to "mutual checks and balances, accountability and responsibility."
In the eighteenth century, freedom of the press created a new method of holding those in power to account, by summoning them to the bar of public opinion, or, to use Bolingbroke's term, "the tribunal of public fame". In general Anglophone political theory was very slow to recognize the significance of freedom of the press for British liberty. Number 15 of Cato's Letters, "Of Freedom of Speech", is perhaps the first sustained defense of free speech, describing it as "the great bulwark of liberty", but I know of no sophisticated analysis of its effects earlier than the one to be found in the Francophone de Lolme. De Lolme, a citizen of Geneva, was impressed by the way a free press can make three kingdoms into one small town. Indeed he maintains public debate in the press has all the advantages and none of the disadvantages of a popular assembly; de Lolme, a former disciple of Rousseau's, was eager to stress the ease with which direct democracy degenerates into tyranny. He is clear, however, that no tyranny can withstand a free press - and the original purpose of his book, first published in Holland for sale in France, was to undermine French absolutism by exploiting this very freedom. De Lolme fully recognized the power of the press as a "mighty political engine," capable of being a check in its own right.
Then there is a third meaning of check, meaning to interrupt or delay. Here check is paired not with "control" but with "clog", a word which originally meant a hobble, and had come to mean any obstacle or brake. In 1698/9 there are repeated references to the opposition's desire to "clog the wheels of government." In 1752 we find Thomas Pownall attacking the contemporary working of checks and balances in the British Constitution: "Thus it becomes the interest of the democratic part to be a constant clog and check upon the measures of the administering power, and to oppose themselves to every new exertion of its influence."  Paine, in Common Sense, chose to understand the theory of constitutional checks in this sense: "for as the greater weight will always carry up the less, and as all the wheels of a machine are put in motion by one, it only remains to know which power in the constitution has the most weight, for that will govern; and though the others, or a part of them, may clog, or as the phrase is, check the rapidity of its motion, yet so long as they cannot stop it, their endeavors will be ineffectual, the first moving power will at last have its way, and what it wants in speed is supplied in time." Speed, of course, might be required for good government, and in Massachusetts those who agreed with Paine that there should only be a single legislative chamber complained that senates "have formerly been a check or clog to business of consequence, requiring dispatch."
American advocates of bicameralism replied that it was important for one legislative chamber to check another, and since, if both chambers represented the people, the purpose of such a check could not be to balance competing interests, it must be to delay hasty decisions. (Although one did not need to be an American to reach such conclusions - de Lolme had already defended bicameralism in similar terms.) In South Carolina in 1784, for example, it was maintained that the case for two representative bodies was that "the division in the legislative power seems necessary to furnish a proper check to our too hasty proceedings." Benjamin Franklin was arguing in this tradition when he defended the idea of two assemblies, saying it was "like a practice he had somewhere seen, of certain wagoners, who, when about to descend a steep hill with a heavy load, if they had four cattle, took off one pair from before, and chaining them to the hinder part of the wagon drove them up hill, while the pair before and the weight of the load, overbalancing the strength of those behind, drew them slowly and moderately down the hill."  There was indeed general agreement that some mechanism to ensure delay was needed so that, in Madison's phrase, it was the "cool and deliberate sense of the community" which prevailed. 
Both checks and balances thus prove to be much more complex notions that one might at first suspect; nor should we be surprised that the linking of the two together presents its own complexities. In Moyle's essay on the constitution of Sparta the word check is frequently used, but "balance" is never used in its Polybian or Plutarchan sense. In Montesquieu the two ideas are kept radically separate: balance is invoked in the context of a discussion of the mixed constitution of the Roman republic as described by Polybius; checks in the context of a discussion of the separation of powers as exemplified by England. Indeed this, I believe, was the general pattern, and modern commentators have been led astray by the fact that it is Adams who first uses the phrase. Manin, for example, concludes that the idea of "checks and balances" develops out of the idea of a mixed or balanced constitution (advocated by Adams) and allows for the active influence of one branch of government on another; while the alternative is the idea of the separation of powers, which provides only for passive or negative "checks". The fact that the idea of a check is here recognized as peculiarly belonging to one tradition, while "checks and balances" is supposed to derive from the other suggests confusion in the argument. In fact the idea of checks and balances implies the bringing together of two analytically and historically distinct traditions, that of the mixed or balanced constitution (a tradition in which the word "check" plays no part) and that of the separation of powers (a tradition which makes no mention of balances).
This argument is supported by the first occasion (as far as I know) on which "check" is used as a political term, in Nedham's True State of the Case of the Commonwealth (1654), when it is immediately counterposed to "balance". Nedham is formulating the first uncompromising argument for a separation of powers (made possible by the existence of an actual separation in the Cromwellian written constitution, the Instrument of Government), and complaining that the Rump Parliament's proposal for biennial Parliaments would have placed "the legislative and executive powers in the same persons by which means in effect they become unaccountable for abuses in government And how easily abuses might have been justified in a parliamentary way, is apparent enough; seeing an opportunity was given in that bill, to the next or any succeeding Parliament (no manner of balance or check being reserved upon them) by claiming an absolute authority to be in themselves, for ever to have continued the power (if they pleased) in their own hands " At first sight it might seem as if the words "balance" and "check" are here being used as equivalent terms: and indeed when Cromwell linked the terms together in 1657 they seem to have been assumed to be equivalents. But they may equally have been meant as alternatives. By the word "balance" it may be that Nedham meant to invoke the powers of the monarch and Lords within the mixed constitution (which included the monarch's power to dissolve Parliament); by the word "check" he may have meant to invoke the power of the Protector under the Instrument of Government to veto unconstitutional legislation. If so the word "check" was being put to use to explain how power would be limited within a constitution where powers were separated. 
Nevertheless, it was tempting to see the English constitution as embodying both a separation and a balancing of powers, and it was easy to slip into using "check" and "balance" as synonyms. As Toland put it, "All the world knows that England is under a free government, whose supreme legislative power is lodged in the King, Lords, and Commons, each of which have their peculiar privileges and prerogatives; no law can pass without their common authority or consent; and they are a mutual check and balance on one another's oversights or encroachments." (This led directly to an appeal to the authority of Polybius.) We have seen Bolingbroke also trying to bring together the ideas (but not the language) of both traditions by stressing the constitutional dependency and independency of both branches of government: first published in The Craftsman in 1730, his argument was republished in 1743 in Remarks on the History of England. In the same year, in Spelman's preface to his translation of Polybius's fragment on the balanced constitution, check and balance once again occur in close proximity, as if virtual equivalents.
But why did Toland's phrase not catch on, as Adams's did? In 1752 Thomas Pownall attacked those "that talk of balance and counter-balance, of one power being constitutionally a check upon another; and that it is constitutionally the duty of these to pull different ways, even when there is no real matter of difference, yet to preserve the equilibrium of power."  Now this is not the old doctrine of the balanced constitution which is under attack, for that had always insisted that the precondition for equilibrium was coalition-making and trimming; what is being attacked here is the new Bolingbrokean doctrine, later to be Adams's doctrine, that the three powers can pull in separate, independent directions and yet establish an equilibrium, and it is this new doctrine which brings the idea of the balanced constitution close enough to the idea of the separation of powers for checks to be routinely identified with balances. Blackstone, we have seen, moves seamlessly from a discussion of checks (first the independent capacity of Commons, Lords, and King to veto legislation; and then the capacity of Parliament to hold the king's agents to account) to a discussion of a triangle of forces. But in Blackstone's account the three forces result in movement not equilibrium. This way of thinking did not lead naturally to a language of checks and balances, or even of "checks and balance," the phrase Noah Webster uses in 1787. In order to understand the power of the phrase we will need to look more closely at Adams's Defense.
We can now see that Adams's phrase involves a further puzzle, beyond the bringing together of two words that belong to very different intellectual traditions: the use of balances in the plural. For most previous writers there had been one balance of forces (as in Polybius and Swift), which trims the ship of state and sustains the mixed constitution, and several checks. What (other than syntactic parallelism) invited the reference to balances in the plural? It seems clear the shift was thought to be particularly appropriate in the context of limits on the power of the legislature: The Federalist refers specifically to "legislative balances and checks," in a list of a series of principles to be adopted in any well-constructed constitution, and an exactly equivalent phrase had been used by Gouverneur Morris in 1776: "The authority of magistrates is taken from that mass of power which in rude societies and unbalanced democracies is wielded by the majority. Every separation of the executive and judicial authority from the legislature is a diminution of political and increase of civil liberty. Every check and balance of that legislature has a like effect."
Later Adams was to identify eight balances in the constitution of 1787: between the states and the federal government; between the House of Representatives and the Senate; between the executive and the legislature; between the judiciary and all the other powers; between the senate and the president in appointments to offices and treaties; between the people and their representatives; between the legislatures of the states and the senators selected by them; between the people and the electoral college which selected a President. Here some of these balances are clearly what would once have been called checks (between executive, legislature, and judiciary). The result (for Adams was no admirer of the new constitution) was "all this complication of machinery, all these wheels within wheels, these imperia within imperiis." I have reproduced these eight in an order of my own, because the first five seem to me a logical consequence of a mixed constitution and a separation of powers within a federal system. But the last three are all cases of a balance between electors and elected, and this involves an idea of balance unknown to Polybius, Swift, and Montesquieu. It is to this idea of balance, central to any account of legislative balances and checks (including that which appears in The Federalist), that I now turn.
There is a simple sense in which at every election the electorate hold their representatives to account, and replace those who have failed to give satisfaction. This fundamental check is, we might say, the essence of the liberty to be found in representative government. Peers, Bolingbroke said, are accountable to God, but MPs to their constituents.  According to the anti-Federalist author who called himself Centinel, in England "the only operative and efficient check upon the conduct of administration, is the sense of the people at large."  But the relationship between the electorate and their representatives is a complex one, and I want to pause over two texts that made a serious effort to analyze it. The first is Edward Spelman's short but incisive introduction to his translation of Polybius on balanced government. Spelman's text was twice reprinted in English (the last edition being known to John Adams, who quotes at length from Spelman's translation in the Defense), and later translated into French for publication during the Revolution. I have already suggested that it was one of the few works that linked check and balance together as equivalents, and it may have played an important part in developing a convenient language for the notion that liberty is primarily established by power restraining power. It is also the first unambiguous defense of party in English, the consensus until then having been that, since there was a single common interest, parties are in principle unnecessary, and that where there are two parties there must be at least one faction.  Spelman, by contrast, argues that "in all free governments there ever were and ever will be parties," and that party conflict is not an effect but a precondition of liberty. The cities of ancient Greece were divided into supporters of aristocracy and democracy, but "it was not the existence of the two parties I have mentioned that destroyed the liberties of any of those cities, but the occasional extinction of one of them by the superiority the other had gained over it. And if ever we should be so unhappy as to have the balance between the three orders destroyed; and that any one of the three should utterly extinguish the other two, the name of a party would, from that moment, be unknown in England, and we should unanimously agree in being slaves to the conqueror."
Party thus becomes a crucial mechanism for checking the power of government: "whatever may be the success of the opposer, the public reaps great benefit from the opposition; since this keeps ministers upon their guard, and, often, prevents them from pursuing bold measures which an uncontrolled power might, otherwise, tempt them to engage in. They must act with caution, as well as fidelity, when they consider the whole nation is attentive to every step they take, and that the errors they may commit will not only be exposed but aggravated." But Spelman also provides a subtle account of party, distinguishing sharply between the motives of a party's supporters, who want to see certain policies adopted, and its leaders, who want power. The thirst for power provides the leaders with a stronger incentive than any disinterested concern for the public good, and opposition provides a training ground for future rulers. There thus exists an inherent tension between a party's leaders and its followers, for the leaders have an incentive to sacrifice their principles to attain power, while the followers, who will never be rulers, have an interest in seeing the powers of government restrained. A simple confirmation of this theory, in Spelman's view, is the complete failure of the political elite to repeal the Septennial Act and institute annual elections: although the whole nation would benefit from such a measure, politicians as a class have an interest in limiting the electorate's ability to control their actions. A similar account appears in de Lolme's Constitution of England, for de Lolme argues that politicians rely on popular support to give them access to power, but as they acquire power and status, as they are promoted, for example, from the Commons to the Lords, the people cease to trust them, and become convinced that their interests are no longer at one with those of their rank-and-file supporters.
In 1787 the proposed federal constitution for the United States necessarily multiplied both checks and balances, for it established a new constitutional tension, that between federal and state powers. Adams's new phrase immediately became the language of the hour. But well before then a new notion of balance had come into existence to supplement the Polybian and Plutarchan balance between monarchical, aristocratic, and democratic institutions. This was the notion of a natural balancing mechanism at work first of all between parties, and then between the governing elite and those they represent. This new conception of representative government made it easy to recognize that there were several balances at work, as well as several checks. Neither Spelman nor de Lolme coined the phrase "checks and balances", but this is a mere accident of history, for the phrase accords well with what they wanted to say, and their notion of a balance between electors and elected is central to Adams's list of the different balances at work in the American constitution.
3. Automatic Machinery. So far I have argued that there is a radical discontinuity between the Polybian or Plutarchan notion of the balance and the new mechanical language of controls, clogs, checks, and of counterpoise, balance, equilibrium that establishes itself after 1697. Second, I have argued that there are several types of check and more than one type of balance, and that it is important to distinguish between them. Thirdly, I have argued that where checks were plural from the beginning, the balance was singular and only became plural with a new account of the role of parties and political leaders in representative government and with the birth of federalism. At this point you might think the idea of checks and balances has been pretty thoroughly explored; this then is the time to turn to that aspect of the new mechanical thinking which seems to me to be missing from modern usages of the language of checks and balances.
Let us start with the translation of Plutarch on the balance which we find in the Dryden edition: "For the state, which before had no firm basis to stand upon, but leaned one while towards an absolute monarchy (when the Kings had the upper hand) and another while towards a pure democracy (when the people had the better of it), found in this establishment of the Senate a counterpoise, which always kept things in a just equilibrium. For the Twenty Eight always adhered to the weaker side, and put themselves like a weight into the lighter scale, until they had reduced the other to a balance." If we take Dryden's translator to be describing, not the decisions of politicians, but the working of a machine, then what we have here is an automatic mechanism, where a feedback loop enables the machine to regulate itself. What is involved here is not a static but a dynamic equilibrium: first the balance tips slightly one way, then the other, but each time it is brought back towards the horizontal. Where, before the establishment of the Senate, it see-sawed wildly, after its establishment it oscillates gently, always close to the horizontal.
Perhaps I am reading too much into this brief passage, for the idea of a self-stabilizing system was not a familiar one in the late-seventeenth century. In 1721 Thomas Gordon could see that the precondition for "control and counterpoise" was "a perpetual struggle: But by this struggle liberty is preserved, as water is kept sweet by motion."  The mixing of metaphors here, as in The King's Answer, shows mechanical thinking pressing at its limits. Gordon, after all, could not use the example of a self-stabilizing system with which we are most familiar, the market, where there is constant movement and change, but where competition works to match supply to demand and to bring profits towards an average rate. Nor would he have been familiar with any self-stabilizing machines. He did not, for example, have the benefit of central heating. Here the temperature in the house oscillates around a norm established by a thermostat: when it falls significantly the furnace is switched on; when it rises the furnace is switched off.
In the second half of the eighteenth century there was, for the first time, considerable interest in self-stabilizing systems, and it was soon claimed that under certain conditions - a separation between legislature, executive, and judiciary; a bicameral legislature; a unified executive; juries judge of law as well as fact; regular elections and a free press - representative government had a self-stabilizing character, where excess in any direction would tend to correct itself automatically. Societies with representative government appear to be in a constant state of agitation, yet we believe them to be peculiarly resilient. Like a tree in a storm, the political fabric bends, but it does not break. We all unthinkingly rely on this idea that certain mechanisms enable the political system to correct its own mistakes when we maintain that an independent judiciary and jury trials are guarantees of liberty, or when we say that it is essential to the democratic process that there should be effective opposition, or when we take it for granted that we are unlikely to live through a violent revolution in England or America. This self-stabilizing system was first identified as functioning within English politics, and then deliberately constructed in the American constitution.
This revolution is of fundamental importance, for if we feel secure in the enjoyment of our liberties it is because we believe that the political system is in some way or other self-stabilizing, that given time the consequences of bad decisions will be mitigated not exacerbated. There are a number of reasons why this revolution has remained invisible. It was not formulated in a "classic" text of political theory. Indeed the ideas involved still remain somewhat unfamiliar and inchoate, so that we have little idea of under what circumstances and to what extent they are true - could one, for example, imagine a Nazi party coming to power within a well-designed constitution, and if not why not? Moreover, to discuss them in an eighteenth-century context it is necessary to talk about ideas of equilibrium in mechanics, a subject of little interest except to historians of science. Above all, the new theory of politics as self-stabilizing was masked by its superficial similarity to the far older theory of Polybius and Plutarch. The classical formulations of the idea of a self-stabilizing system, however, were designed to describe political systems which had the capacity to evolve into either monarchy, aristocracy, or democracy, but in fact stabilized in an in-between condition. What made this equilibrium possible was not just an arrangement of political institutions, but also a set of extra-institutional powers, or what one eighteenth-century commentator called "weight in the community" - even if Polybius did not make this explicit, any eighteenth-century theorist familiar with Harrington's Oceana (1656) would have read this back into the text.  Thus Trenchard and Moyle wrote that "this balance [the constitution of England] can never be preserved but by a union of the natural and artificial strength of the kingdom or otherwise the government is violent and against nature." The new theory, by contrast, assumed that an overwhelming preponderance of power lay with a relatively undifferentiated "people", but that, despite there being no equilibrium in the social distribution of power, a self-stabilizing political system could exist.
Precisely because it involved a rejection of the traditional idea of a mixed government, the only system for which the claim that it was self-stabilizing had previously been made, many contemporaries found the new theory incomprehensible, implausible, or paradoxical. It relied, they recognized, on the idea of checks on power, it claimed that the checks involved were not simply "parchment barriers," but as far as they could see the checks were after all only "checks on paper," that is to say they relied purely on institutional mechanisms. Their puzzlement and incomprehension continues to interfere with our ability to understand the intellectual revolution that had taken place.
Let us go back to the mechanical metaphor. The power of this depends partly on the quality of the clockwork mechanism one has in mind. The heart, which de Mornay likened to a clock constructed by God, does not beat steadily, but sometimes races, and for John Donne in the early seventeenth century clockwork was a symbol of unreliability, to be compared unfavorably with the genuinely regular movement of the sun through the heavens. René Descartes (1596-1650) obviously represents a key moment of transition, for in arguing that animals were mere machines he not only deprived animals of intelligence; he also attributed remarkable capacities to mere machines. It took time for men to construct in their minds the idea of a perfect mechanism, of what Trenchard, at the end of an essay on the mechanical philosophy, described as "a watch which will go for a thousand years" without winding or mending. First Arnold Geulincx (1624-1669) and then Gottfried Leibniz (1646-1716) took the idea of mechanical perfection even further when they claimed that the mental world and the physical world correspond only because both are automata which have been perfectly synchronized, two clocks beating as one, unfailingly keeping time.
This theoretical concept of the perfect mechanism takes form at roughly the same time as a quite different metaphor which contributed equally to the scientific revolution, that of the law of nature. The idea of a law as the expression of uniformity and regularity also involved the mental construction of a new species of perfection. Robert Boyle is an important pioneer in the use of both metaphors for regularity, that of the machine and that of the law, in a world where neither machines nor laws actually performed predictably. It is worth remembering that regular itself is a dead metaphor, derived from the term for a monastic rule; de Quincey in 1722 appears to have been the first to have used it to mean constant and uniform, in opposition to irregular - to use it in the sense we now take for granted. 
In order to be accurate, clocks have to be designed to continue marking regular intervals of time even as the arc of the pendulum diminishes, or the spring unwinds. All good clocks are in that sense self-regulating, and the history of clockwork is a history of regulatory mechanisms such as the verge-and-foliot escapement and the fusee. But a clock cannot tell when it has gone wrong and correct itself. Clocks lack feedback mechanisms, and to think of the universe as clockwork is to invite the notion that God may make occasional adjustments, as Newton believed He did to the orbits of the planets. Harrington insisted that a constitution, if constructed according to the right principles, could continue for ever, a self-regenerating system, but the claim explicitly involved a comparison between the political and the divine architects.
However a century after what we might call the mechanical revolution, a second, much less well-understood revolution took place, a revolution which saw the invention of self-regulating or self-governing or self-stabilizing machines. A simple example is the fan-tail windmill, where the fan-tail points the windmill into the wind, and constantly adjusts the direction in which the windmill points as the wind changes direction. The fantail is an eighteenth-century English invention - one apparently never adopted in France, where millers preferred to steer their windmills into the wind, not leave them to their own devices. It is on the basis of contemporary windmill technology that James Watt invented in 1788 the most famous self-regulating mechanism of the industrial revolution, the centrifugal speed governor for steam engines. Around the same time self-regulating mechanisms that had long been known were finding new uses - the thermostat, for example, and the ball-cock valve. All such machines involve - though the term itself is a twentieth-century one - some sort of feedback mechanism.
At the same time, and almost ahead of the technological revolution, what we might call mind machines (remember Adam Smith describes theoretical systems as "imaginary machines" ) are being invented (again in the English-speaking world) which have self-regulating qualities: Hume invents the modern theory of the balance of trade in 1750, and Smith formulates what we now call the market mechanism (he does not use the term "mechanism" himself, but he would have acknowledged that the market was an imaginary machine) in The Wealth of Nations (1776). The whole point of the market mechanism is not that it is a machine, but that it is self-regulating or self-stabilizing, that it is a feedback system. Modern economics, as much as modern natural science, is thus dependent on a new understanding of the possibilities of mechanical systems, for even imaginary machines, if they are to be seen to work, must abide by recognizable mechanical principles. Even natural science needed the concept of self-regulation: Shaftesbury, as early as 1709, describes the mechanical philosophy as relying on "some exquisite system of self-governed matter," and I take it self-governed here means in effect self-regulating. 
It is worth noting that the process described by Spelman and de Lolme, the new balance between politicians and the public, is one of constant fluctuation around an equilibrium: government provokes opposition, opposition moves into government, and government provokes opposition. The process is never at rest, but is constantly self-stabilizing, just like the market or the fan-tail windmill. It implies, in fact, the idea of dynamic rather than static equilibrium, for what is at work is a feedback mechanism. Indeed any careful formulation of the claim that the people control their representatives through elections involves an appeal to a feedback mechanism. It is also worth stressing that Nedham and Harrington, who seem in so many respects to be the founders of the modern republican tradition, are systematically opposed to feedback mechanisms. They want a wholesale rotation or revolution in elected representatives at every election, rather than seeing elections as an opportunity to assess the performance of the people's representatives. And they want political discussions to take place in secret, as in Venice, not in public.  Their assumption is that any passage of time represents an opportunity for corruption, while for later theorists time provides scope for correcting mistakes and adjusting to developments.
We can see the new, contrasting conception best in a passage from de Lolme:
As the representatives of the people will naturally be selected from among those citizens who are most favored by fortune, and will consequently have much to preserve, they will, even in the midst of quiet times, keep a watchful eye on the motions of power. As the advantages they possess will naturally create a kind of rivalship between them and those who govern, the jealousy which they will conceive against the latter will give them an exquisite degree of sensibility on every increase of their authority. Like those delicate instruments which discover the operations of nature while they are yet imperceptible to our senses, they will warn the people of those things which of themselves they never see but when it is too late; and their greater proportional share, whether of real riches or of those which lie in the opinions of men, will make them, if I may so express myself, the barometers that will discover, in its first beginning, every tendency to a change in the constitution.
The representatives thus serve as a thermostat, enflaming or damping down public opinion depending on the presence or absence of a threat to liberty and property. Again, the process involves constant movement, as representatives compete simultaneously for power and public support, but as long as the circuit of election, representation, sensitivity, publicity, and new elections is unbroken, the mechanism to check power will continue to function. De Lolme, we have seen, likens the representatives to barometers not thermostats, for like barometers they act on men's minds. But while a barometer changes one's behavior, encouraging one to set to sea or carry an umbrella, one's resulting behavior does not in itself affect the weather. In politics, by contrast, the acute sensitivity of the elected representatives actually serves to change the political situation, as a result of the information being fed back to the public, in the same way that a thermostat serves to change the temperature in the room by supplying information to the furnace. What de Lolme is describing is a self-regulating system, and it is because his understanding of politics reaches this level of sophistication that we find him in later editions of his book criticizing Adam Smith's view that a standing army is not a threat to liberty if the sovereign is the supreme commander and the social elite supply the officer caste: "The author we are quoting has deemed a government to be a simpler machine, and an army a simpler instrument, that they in reality are." It is only when we see that de Lolme's understands England's constitutional machinery to be self-stabilizing that we can understand just how far from simple he thinks it is. We can also recognize why he was in a good position to identify and admire Smith's "great abilities." 
It was the need to find checks and balances with which to control representative democracy which most concerned the framers of the American Constitution. When Adams was asked by the state of Massachusetts to preside over a state constituent convention in 1820 (a convention called to revise the constitution of 1780, which Adams had drafted single-handed), he was praised for "demonstrating to the world, in his defense of the constitutions of the several United States, the contested principle, since admitted as an axiom, that checks and balances in legislative power are essential to true liberty." But the great political work which sought to clarify and formulate the new understanding of politics which came to be embodied in the phrase "checks and balances," and draw from it a new design for the machinery of politics, was not Adams's Defense but Hamilton and Madison's Federalist, and it is only by putting that work in the sort of context I have constructed here that we can hope to measure its originality and its success. Outside America The Federalist remains largely unread - Isaiah Berlin, for example, who sometimes gave the impression of having read everything worth reading, never bothered to read it.  But unread too are the key texts in the development of the new theories of checks and balances, the texts of Nedham, Moyle, Trenchard, Gordon, Bolingbroke, Blackstone, Spelman, and de Lolme; instead The Federalist is read in the context of Hume (who had, it is true, been the first to recognize that an increase in scale could itself serve as a check upon the democratic element in the constitution). Hume pioneered the idea of self-regulating systems in economics but not in politics.  Indeed he felt sure that in the long run the British constitution would fail to correct its own faults and would dissolve into tyranny or democracy.
In Federalist 50 Madison (for those unfamiliar with the text I should explain that we know who wrote each of the essays which appeared under the by-line of Publius) rejects the idea that the working of the constitution can be supervised by some external body. He then begins no. 51 with this question:
To what expedient, then, shall we finally resort, for maintaining in practice the necessary partition of power among the several departments as laid down by the Constitution? The only answer that can be given is that as all these exterior provisions are found to be inadequate the defect must be supplied by so contriving the interior structure of the government as that its several constituent parts may, by their mutual relations, be the means of keeping each other in their proper places. Without presuming to undertake a full development of this important idea I will hazard a few general observations the great security against a gradual concentration of the several powers in the same department consists in giving to those who administer each department the necessary constitutional means and personal motives to resist encroachments of the others. The provision for defense must in this, as in all other cases, be made commensurate to the danger of attack. Ambition must be made to counteract ambition. The interest of the man must be connected with the constitutional rights of the place. It may be a reflection on human nature that such devices should be necessary to control the abuses of government. But what is government itself but the greatest of all reflections on human nature? If men were angels, no government would be necessary. If angels were to govern men, neither external nor internal controls on government would be necessary. In framing a government which is administered by men over men, the great difficulty lies in this: you must first enable the government to control the governed; and in the next place oblige it to control itself. A dependence on the people is, no doubt, the primary control on the government; but experience has taught mankind the necessity of auxiliary precautions.
Here the conviction, so clearly formulated in Cato's Letters, that "whilst men are men, ambition, avarice, and vanity will govern their actions" has been turned from a psychological principle into the fundamental principle of the constitution.
Indeed in Cato's Letters, a work that Madison must certainly have known, Trenchard had momentarily formulated this general constitutional principle himself. Taking as his premise that "there has always been such a constant and certain fund of corruption and malignity in human nature, that it has been rare to find that man, whose views and happiness did not center in the gratification of his appetites", Trenchard concluded that experience had shown there was only one type of free government that could survive: one where
the power and sovereignty of magistrates in free countries was so qualified, and so divided into different channels, and committed to the discretion of so many different men, with different interests and views, that the majority of them could seldom or never find their account in betraying their trust in fundamental instances. Their emulation, envy, fear, or interest, always made them spies and checks upon one another The only secret therefore in forming a free government is to make the interests of the governors and the governed the same, as far as human policy can contrive. Liberty cannot be preserved any other way.
But Trenchard expected the conflict between political leaders and the institutions with which they identified to be far more ruthless, far less successfully channeled into a harmless jockeying for position, than Madison did. "Disgrace, torture, and death", he tells us, should be "the punishment of treachery and corruption." For hanging, drawing, and quartering, Madison substituted ambition and place-seeking.
Bernard Manin has correctly said that the system of internal controls which Madison is describing can properly be termed a self-enforcing equilibrium. One might then say - for it is the same idea expressed in different language - that the constitution is intended to be a self-regulating machine. We have seen that this was already de Lolme's idea, and that he had elaborated this idea most clearly in his account of "the primary control," the relationship between the government and the people.
We do not know for sure that Madison had read de Lolme. It seems highly unlikely that he had not read an author whom Hamilton admired and whose book Adams (who shared de Lolme's preoccupation with the British constitution) had described as "the best defense of the political balance of three powers that ever was written". Adams's enthusiasm rather blinded him to the fact that de Lolme was not interested in a balance of monarchy, aristocracy, and democracy (Adams's primary concern), but rather in a balance of executive, legislative, and judiciary and, in order to achieve this, in legislative balances and checks. In Federalist 70 Hamilton, who wanted a strong and unified executive, stated that he and de Lolme thought as one on the question of executive power, and made his own the judgement of Junius, that de Lolme was "deep, solid, and ingenious."  I rather suspect that Madison had read de Lolme and read him with care, for every step of Madison's argument in No. 51 is foreshadowed in de Lolme.
No quotation from Madison is more famous than the statement that "If men were angels, no government would be necessary. If angels were to govern men, neither external nor internal controls on government would be necessary." De Lolme had made a similar argument: in a world where men "had neither any ambition, nor any other private passions," then direct democracy would be practical, but "in such a society, and among such beings, there would be no occasion for any government." And indeed this whole chapter (book 2, chapter 5) on the evils of direct democracy might be said to illustrate Madison's astonishing claim - the decisive attack on the notion that it is executives not legislatures that need to be checked - that "Had every Athenian citizen been a Socrates, every Athenian citizen would still have been a mob." We have seen Madison arguing that every attack must be met with an equivalent defense, that ambition must counteract ambition. De Lolme's response to the excessive concentration of power is the same: the people must employ "for their defense the same means by which their adversaries carry on their attack using the same weapons as they do, the same order, the same kind of discipline the arts and ambitious activity of those who govern will now be encountered by the vivacity and perseverance of opponents actuated by the love of glory."  Underlying the principle of ambition counteracting ambition is the conviction that there can be no disinterested exercise of power, and that mere rules and regulations can never be effective checks. As de Lolme says, "those who are in a condition to control it [power] from that very circumstance become its defenders." Thus "the people are necessarily betrayed by those in whom they trust." The only remedy to an excess of power is therefore to turn power against power, ambition against ambition. De Lolme was in fact the first theorist of legislative balances and checks, of the measures required to control an overwhelmingly powerful legislature. No reading could have been more apposite for the authors of the Federalist, particularly as de Lolme had no interest in what one might term the antiquated elements of the British constitution, such as an hereditary aristocracy, a limited franchise, or an executive veto, but was interested only in those elements which could be shown to be superior to the democracy of Rousseau's Social Contract, which, along with classical republicanism, is as much de Lolme's subject as is the English political system.
Perhaps Madison had also read or reread Spelman just before writing Federalist 51, for we catch an echo of Spelman's argument that "it was not the existence of the two parties I have mentioned, that destroyed the liberties of any of those cities, but the occasional extinction of one of them, by the superiority the other had gained over it. And if ever we should be so unhappy as to have the balance between the three orders destroyed, and that any one of the three should utterly extinguish the other two, the name of a party would, from that moment, be unknown in England, and we should unanimously agree in being slaves to the conqueror" in Madison's statement, towards the end of Federalist 50, that "an extinction of parties necessarily implies either a universal alarm for the public safety, or an absolute extinction of liberty." But, whether or not Madison was consciously aware of his predecessors he shared with them a common purpose: the construction of a mental machine, a political system in which threats to liberty would be automatically counterbalanced, in which "a kind of rivalship" would pit ambition against ambition, with the unintended consequence that liberty would be secured.
4. Elective Despotism. In this paper I have traced the origins of the idea of checks and balances. I hope I have shown that, far from being an idea so straightforward that it has no history, it in fact has a double origin. On the one hand, as Noah Webster's "checks and balance," it is a complex amalgam of two theories which, until the middle years of the eighteenth century, were assumed to be incompatible, the theory of mixed government and the theory of the separation of powers. Here what made it possible to bring checks and balances together was a new understanding of the possibility of an equilibrium of independent (and also unequal) forces, so that the powers within a mixed government could be thought of as always separate rather than as being obliged eventually to act in concert. The importance of this theory (born of opposition to Walpole) was that it legitimized opposition to the government, and rejected the traditional quest for consensus. On the other, as Gouverneur Morris's "every legislative check and balance," it derives from the view that in a representative democracy the greatest danger is that the legislature will acquire the defects of a popular assembly, and that if it does the executive and the judiciary may prove incapable of checking its actions. The legislature had therefore to be balanced as well as checked: by elections, by political opposition or factional division, by public opinion, by a second chamber, by a strengthened executive. The importance of this theory (born both of a recognition that power was now concentrated in the House of Commons, and of a critique of Rousseau and ancient republicanism) was that it identified and addressed the possibility of a "tyranny of the majority". 
Thus checks and balances came to be linked by two quite different routes. In addition the checks or balances (for once the two were coupled together the distinction between them became increasingly difficult to sustain) that were understood to be at work changed radically over time, as the veto was supplemented by the idea of accountability, and as the electorate, the political party, and the press came to be recognized as having a crucial part to play in preventing the abuse of power. By coining the phrase "checks and balances" Adams thus made it possible to link together three distinct traditions - mixed government (Polybius), separation of powers (Montesquieu), the need for precautions against the tyranny of the majority (de Lolme) - within a single catch phrase. This was a rhetorical, not an intellectual, achievement, for Adams did not grasp the full significance of the new legislative balances and checks identified by Spelman and de Lolme. Although he had some sense that the English constitution was self-regulating, he did not go much beyond Polybius and Montesquieu in his understanding of why this was so. Nevertheless he was convinced that "the English constitution is, in theory, both for the adjustment of the balance and the prevention of its vibrations [my italics], the most stupendous fabric of human invention."
So the history of the idea of checks and balances is much more complicated than has previously been recognized, and that history can only be understood in relation to the idea of a constitution as a machine, sometimes a self-regulating machine. Without mechanical thinking, the first form of systems analysis, there could have been no "modern" (as opposed to ancient or medieval) form of liberty. The idea of limited government, of checks and balances, originally depends on the metaphor of a constitution as a machine in a state of equilibrium, and in its sophisticated form depends on some practical acquaintance with feedback mechanisms. For Madison, representation was "this great mechanical power by the simple agency of which the will of the largest political body may be concentered and its force directed;" hence the need to check and balance it with care. In this sentence the phrase "mechanical power" is to be taken seriously as a tool with which to think. I started with Nietzsche's statement that truths are really metaphors. If Nietzsche is right, the first task of the historian of ideas must be to bring back to life all the long dead metaphors. I have tried to make a start here by showing that the metaphor of "constitutional machinery" was once vigorous and capable of doing real work; indeed it is to this metaphor that we owe all but the most elementary components of the idea of limited government.
For it should now be apparent that the whole modern tradition of constitutional theory, from Trenchard and Moyle onwards, is concerned to limit the power of government. Initially the emphasis was on limiting the executive, but over time checks-and-balances theorists became increasingly concerned to limit government in general, and eventually they came to see the chief danger as coming from the legislature in particular. Trenchard and Moyle were supposed to have said (and Fletcher of Saltoun certainly did say in 1698) "For not only that government is tyrannical which is tyrannically exercised, but all governments are tyrannical which have not in their constitution sufficient security against the arbitrary power of their prince."  For Fletcher and his associates the executive was the problem. Bolingbroke made a similar point in much more general terms: "tyranny and slavery do not so properly consist in the stripes that are given and received, as in the power of giving them at pleasure, and the necessity of receiving them, whenever and for whatever they are inflicted."  And we have seen Gouverneur Morris writing in 1776 of the need to diminish political liberty, the freedom of action of our rulers, in order to increase civil liberty: it was checks on the legislature that he had particularly in mind.
These last two quotations from Fletcher and Bolingbroke are examples of what Quentin Skinner has termed the neo-Roman republican theory: the theory that for liberty to exist it is not sufficient that there is no tyranny; rather it is necessary that no one has the power to act tyrannically. As we have seen, checks-and-balances theorists maintained that where someone has the power to act tyrannically, tyranny is the inevitable outcome. On Skinner's account neo-Roman theorists were committed to a particular type of guarantee against tyranny: they held that a state was free if was governed by its citizens, either assembled or through their representatives. Any claim to a prerogative power which could be exercised against the wishes of the representatives of the political community was (as in the quotation from Fletcher) a claim to a tyrannical power. Thus if, after the Restoration, neo-Roman theorists claimed to be able to accept the idea of monarchy, they could do so only because they intended to make the monarch a merely symbolic figurehead without any real power, a Venetian doge. Rousseau and Paine, one might comment, would have understood this argument for autonomy or self-government: a political community must be its own master if it is to be no one's slave.
But the argument for popular sovereignty is not the only way of responding to the problem of the potential for tyranny, and it is the alternative to it which I have been exploring here. This response is based, in the first place, on the recognition that representative government can never be the same as self-government: it acknowledges the problem of corruption and of the emergence of elites. This was a problem which preoccupied the true Whigs in their opposition to the court Whigs. Second, it faces up to the fact that the majority may wish to tyrannize the minority. "It is a mistaken notion in government," writes Gordon in 1721, "that the interest of the majority is only to be consulted, since in society every man has a right to every man's assistance in the enjoyment and defense of his private property; otherwise the greater number may sell the lesser, and divide their estates among themselves; and so, instead of a society, where all peaceable men are protected, become a conspiracy of the many against the minority."  Here the key issue was not so much property but, as Gordon immediately went on to emphasize, religion, for the House of Commons had repeatedly shown itself hostile to the rights of religious minorities. In order to recognize this problem of majority tyranny a conceptual shift was necessary, for it is not until 1691 that the word "majority" is used in the sense of "the greater number or part" (rather than, for example, to refer to the age of majority), the assumption until then being that the decisions of an assembly properly reflected a consensus. And the passage from Gordon I have just quoted may be the first occasion on which "minority" is used to mean the smaller number - the earliest example given by the OED is from 1736.
This shift involved rejecting the view, which Skinner says lay at the heart of neo-Roman political theory, that one could think in terms of "the body" of the political community, and attribute a single will to the nation; and it thus prepared the ground for an eventual recognition that party-political divisions might be essential to the preservation of liberty. Advocates of checked and balanced government held that the power of the state must be limited so that it is incapable of summoning the strength to act tyrannically. "Only the checks put upon magistrates make nations free; and only the want of such checks makes them slaves," writes Trenchard in 1722 in an essay on "The encroaching nature of power, ever to be watched and checked", but as he goes on to develop this argument it becomes clear that he is not simply concerned to check the power of the executive and make it subordinate to the legislature, but rather to make the more general claim that all power tends to corrupt and must be confined within limits: hence the reluctance of Parliaments to vote for annual elections. "The Romans, who knew this evil [the divergence between the interests of the rulers and the ruled], having suffered by it, provided wise remedies against it; and when one ordinary power grew too great, checked it with another. Thus the office and power of the tribunes was set up to balance that of the consuls And when the authority of the tribunes grew too formidable, a good expedient was found out to restrain it" by requiring that the tribunes always act unanimously.  Even the representatives of the people needed to be restrained in the cause of liberty. John Adams regarded it as a fundamental axiom that "A single assembly is liable to all the vices, follies, and frailties of an individual." "An elective despotism was not the government we fought for," wrote Jefferson in 1784, "but one which should not only be founded on free principles, but in which the powers of government should be so divided and balanced among several bodies of magistracy, as that no one could transcend their legal limits, without being effectually checked and restrained by the others." 
The argument that power tends to corrupt was not new: it had been clearly formulated by Nedham in The Excellencie of a Free State. Earlier theorists would surely have accepted that power has, as Nedham explained, its own peculiar temptations:
The reason is, because (as the Proverb saith) honores mutant mores; "Honours change men's manners;" accessions, and continuation of power and greatness, expose the mind to temptations: they are sails too big for any bulk [i.e hull - cf OED s.v. bulk] of mortality to steer an even course by.
The kingdoms of the world, and the glories of them, are baits that seldom fail when the Tempter goes a-fishing, and none but He that was more than man, could have refused them.
But Nedham was able to place a whole new emphasis on the tendency of power to corrupt because he had a new theory, the separation of powers, of how it was possible for a people "so to regulate their affairs, that all temptations and opportunities of ambition, may be removed out of the way." 
Thus the same neo-Roman definition of individual liberty as the antithesis of slavery could be used for a variety of political purposes. Skinner, in arguing for the coherence of the neo-Roman conception of liberty, appears to think that a doctrine of popular sovereignty always follows from it - and indeed Trenchard ends his essay with the claim that the Roman mechanism of "an appeal to the people" is the best of all protections for liberty. But even for Trenchard (who acknowledges that the people may sometimes, if rarely, abuse their sovereign power), and for Gordon (who fears a conspiracy of the many against the minority), and even more clearly for Nedham (who had been reprinted in 1767), for de Lolme and for the founding fathers, what also followed from the neo-Roman account of liberty was an argument for the separation of powers and for checks on the power of the legislature as well as the executive, for any concentration of power (even in the hands of the majority) was now held to be dangerous. Even now this is not - in Great Britain at least - simply an academic issue, for a debate between those who insist on the need to maintain a unified Parliamentary sovereignty (which, it is claimed, is the only reliable guarantee against tyranny) and those who are willing to see sovereignty distributed through the organs of a federal Europe (which, it is claimed, is the best way of taming the nation state, and of preventing the emergence of a new Hitler or Mussolini) has been central to British political debate over the last half century.
The new argument for limited government did not simply displace existing discourses. Historians of political thought have tended to write as if there were a number of alternative languages - ancient constitutional or Cokean; natural rights or Lockean; republican or neo-Harringtonian - available in the eighteenth century for discussing politics. To stress the importance of one language, it has been assumed, implies a reduction in the significance of the others, so that John Pocock's work has been read (and is intended to be read) as implying that republican discourse was much more important than the argument from natural rights. But this way of thinking does not do justice to the texts we have been considering. No one had a higher opinion of Locke than Moyle (who quotes with approval the view that the Two Treatises are "the ABC of politics")  yet Moyle is one of the founders of the new mechanical language and an admirer of classical republics. So too in Cato's Letters Trenchard and Gordon seem to oscillate from one moment to the next between a Lockean and a republican language. For these thinkers, however, these were not several alternative languages for discussing politics; they were rather several languages, each of which was appropriate for a different aspect of politics. Locke established natural rights and the principle of government by consent, thereby providing a theoretical foundation for liberty (including religious liberty). The neo-Roman republican theory defined liberty as the absence of the capacity to tyrannize. And the language of checks and balances explained how a constitution could be constructed so that liberty was maximized. Just as one would expect an architect to be familiar with issues of the aesthetics of form, structural engineering, and quantity surveying, so the language of politics had a normative discourse of rights, a theory of liberty grounded in an account of human psychology, and a value-free account of constitutional engineering. These were not seen as alternative languages: each was taken (one can see the process at work in Cato's letters 60 to 62, for example) to imply the next. They were mutually supporting. Similarly in The Federalist Lockean and Humean arguments are taken to be complementary, not (as a modern reader might naturally assume) at odds with each other.
I promised that my history of "checks and balances" could help us rethink our own political commitments, and it will if it makes us take constitutional machinery seriously. This should be evident from the way in which my account of the implications of neo-Roman arguments diverges from Skinner's. But one must recognize that to seek to limit government so that it cannot act tyrannically, to check and balance, to internally divide it so that power is set against power, may well be to weaken its capacity to do good as well as ill. In the United Kingdom we have a strong and powerful government: there is no effective division between legislature and executive; the powers of the second chamber are weak (it cannot, for example, oppose legislation to implement manifesto commitments made by the governing party, nor can it initiate budgetary measures); the judiciary is not fully independent; the legislature has a limited and diminishing capacity to hold the executive to account; the first past the post system tends to ensure one party government; the government can call elections whenever it chooses; the independence of the civil service (a check new in the nineteenth century) is under threat; and so on. Proper checks and balances would mean a far weaker government, a government which would find it much harder to "deliver", to use the word which is currently the most popular in government speeches. A weaker government might have to recognize that it had no option but to hand over the task of managing schools, universities, hospitals to genuinely independent management, management released from the checks and balances that are entirely appropriate in a political context. This is an old argument, and I hardly need to rehearse it at any length here, but it is worth noting that it is different from, even if it often points in the same direction as, arguments against government monopolies and in favor of competition. The standard "Thatcherite" arguments for privatization of public services derive from Smith, while this argument derives from Madison.
But I have a new argument to make as well. Harrington believed that his constitution could remain unchanged and unchanging because the ballot and rotation would prevent corruption, and so would constantly return the political system to its original starting point. He mocked Machiavelli for thinking that political reform required the irregular intervention of bold politicians who would bring the political system back to its founding principles; his system was constantly self-reforming. We can still see something of this way of thinking in the arguments of Spelman and de Lolme. Their balance may be dynamic, but its oscillations or vibrations do not alter the system. Madison, it seems to me, takes a cautious step away from this way of thinking. When he discusses the conflict between factions he assumes that factions can simply cancel each other out. But when he talks about the parts of government keeping each other in their proper places, he envisages them as being in a constant struggle for power, an unending series of attacks and counterattacks. Out of this struggle will come political decisions and political action. In such a world there will be (as in the international struggle for power which constantly recreates a balance of power) long-term winners and losers. As the decades pass the system may begin to be quite different from what it was at its first foundation. In rejecting external control Madison was rejecting the possibility of restoring the American constitution, as Machiavelli believed all constitutions needed periodically to be restored, by recalling it to its founding principles; but in his description of internal control he was also rejecting the Harringtonian conviction that the constitution could be prevented from ever changing. He was, it seems to me, proposing to let the system run, on the presumption that as long as power was divided against power, as long as there were adequate barriers to a monopoly of power, the system could be allowed to evolve over time. In other words, what Madison had in mind was something much more like a market (he was an early reader of Smith), which is self-stabilizing but never repeats itself, than like a fan-tail windmill, which comes back again and again to the same starting point.
Two surprising consequences follow. The first affects our idea of a written constitution, for although Madison was defending a written constitution, he was thinking in terms of a flexible and developing system, despite the fact that the two are normally thought to be, if not incompatible, then certainly in a dynamic tension. The second affects our idea of checks and balances, for if Madison had the idea, not just of a dynamic equilibrium, but of a dynamic evolution, of what one might call a political ecology, in which equilibria are constantly being established and reestablished, but change radically over time, then the idea of checks and balances is not necessarily as static, as fixed, as negative as is usually assumed. Unlike Montesquieu, Madison did not imagine that the various organs of government could be required to act in concert; rather he envisaged a system where the conflict between the organs of government would have unintended consequences that were beneficial to the public. A political system in which there are numerous checks and balances could also be one which is flexible, adaptable, resilient. It is precisely because the idea of checks and balances can be used to think about dynamic interactions, not just restrictions on freedom of action or static equilibria, that it contains a largely untapped potential to help us think about political change, and about a central political problem: how a political system can be engineered to be both limited in its power to do evil, and at the same time quick to adapt to changing circumstances. Trenchard and Moyle were concerned that "the very excellence of our government betrays it to some inconveniences, the wheels and motions of it being so curious and delicate that it is often out of order," and this was because they conceived of the constitution as a complex mechanism incapable of self-regulation. Madison, by contrast, imagined a constitution so curious and delicate that it need never go out of order, and this not because it would never go wrong, but because it would have the capacity to right itself when it did go wrong. If Trenchard and Moyle were the first of the political engineers, he was the founder of a new discipline which we may term (despite the obvious anachronism) political cybernetics.
What makes adaptation possible is that checks and balances not only serve to secure our liberty, they also entrench disagreement into the political system, and thus protect out collective capacity for critical reflection; we need them not only as a bulwark against tyranny, but also to preserve our capacity for innovation. Only where conflict is institutionalized within government will debate and disagreement flourish, in the process encouraging novelty without (the claim is a remarkable one) endangering stability.
1 I have modernized spelling and punctuation of quotations and titles in the text, but not the footnotes. An earlier version of this paper was given as the keynote address to the annual meeting of the British Society for Eighteenth Century Studies, 2002. I am grateful for many helpful suggestions, particularly from Blair Worden and Paul Rahe (who both told me to read Nedham, amongst much else), Harold Cook (who told me to read Mayr), Iain Hampsher-Monk (who told me to read Blackstone), and Claude Rawson (who told me to read Ellis).
2 Stanley Pargellis, "The Theory of Balanced Government," in Conyers Read ed., The Constitution Reconsidered (New York: Columbia University Press, 1938), 37-49, p. 37.
3 Invisible is a slight, but only a slight, overstatement. In addition to Manin's chapter (on which see below, p. ** [and add reference to his article in The Critical Dictionary of the French Revolution, 1989]) there is Pargellis, "Theory of Balanced Government", and E.P. Panagopoulos, Essays on the History and Meaning of Checks and Balances (Lanham Md.: University Press of America, 1985). Also relevant to the subject of this paper is [Anon.], "Organic and Mechanical Metaphors in Late Eighteenth-Century American Political Thought", Harvard Law Review 110 (1997), 1832-49. But the work which most closely touches on the topics I address here is chapter two of A.O. Lovejoy, Reflections on Human Nature (Baltimore: John Hopkins University Press, 1961), "The Theory of Human Nature in the American Constitution and the Method of Counterpoise" (pp. 37-65). Lovejoy there offers a reading of Federalist 10 with which I agree: I think this "static" reading (which takes Madison's argument on factions to be the equivalent of Locke's on religious sects in the Letter Concerning Toleration - cf. John Locke, Political Writings, ed. D. Wootton [Harmondsworth: Penguin Books, 1993], p. 429) is compatible with, but distinct from, the "dynamic" reading of Federalist 51 which I offer at the end of this essay. It is important to note a difference between the logic of Federalists 10 and 51: 10 is about ensuring that no faction has a majority in the legislature while 51 is about ensuring there is a balance of power between the various institutions and officers established by the constitution. 10 is consequently about overbalance; 51 about equilibrium. Overbalances are static; equilibria, because they have to be constantly re-established, are dynamic.
4 Garry Wills, Explaining America: The Federalist (Garden City: Doubleday, 1981), 117. Others err in the opposite direction, e.g. Roger Scruton, A Dictionary of Political Thought (London: Pan Books, 1985), s.v. "checks and balances", which suggests the phrase derives from Jefferson's Notes on the State of Virginia (written 1784, first American edition 1787), on which see below.
5 See M.J.C. Vile, Constitutionalism and the Separation of Powers (2nd ed., Indianapolis: Liberty Fund, 1998) and W. B. Gwyn, The Meaning of the Separation of Powers (New Orleans: Tulane Studies in Political Science, No. 9, 1965).
6 OED CD-Rom, s.v. check.
7 Nietzsche, "On truth and lie in an extra-moral sense", in The Portable Nietzsche, trans. Walter Kaufman (London: Chatto and Windus, 1971), p. 46.
8 The term "Cambridge School" has become a conventional way of referring to the work of John Dunn, John Pocock, Quentin Skinner and their pupils. On linguistic change see for example Q. Skinner, "Language and Social Change" , in James Tully ed., Meaning and Context (Princeton: Princeton University Press, 1988), pp. 119-132. I should stress that my own efforts here are rather primitive in that I have made little use of electronic texts. A pioneering example of what can be done with modern technology is provided by Nicholson Baker, "Lumber", in The Size of Thoughts: Essays and Other Lumber (London: Chatto and Windus, 1996), 207-355.
9 e.g. R. Tuck, Natural Rights Theories (Cambridge: Cambridge University Press, 1979), p. 1; Q. Skinner, Liberty Before Liberalism (Cambridge: Cambridge University Press, 1998), pp. 107-20 (on which see the review by Blair Worden, London Review of Books (1998:3).
10 J.P. Kenyon ed., The Stuart Constitution, 1603-1688 (Cambridge: Cambridge University Press, 1966), p. 21, unreliably quoted in James Harrington, Political Works, ed. J.G.A. Pocock (Cambridge: Cambridge University Press, 1977), p. 19.
11 Harrington, Political Works, ed. Pocock, pp. 20, 22 (referring to Philip Hunton, A Treatise of Monarchy (1643), pp. 69, 23.
12 Hunton, Treatise, p. 28.
13 Hunton, Vindication (1651), p. 44.
14 OED CD-Rom, s.v. mechanics, mechanism, machine, engine, automaton.
15 Otto Mayr, Authority, Liberty and Automatic Machinery in Early Modern Europe (Baltimore: Johns Hopkins University Press, 1986), pp. 47-8. Mayr's excellent book fails to note the republican use of mechanical imagery.
16 John Trenchard and Thomas Gordon, Cato's Letters (1720-3), ed. Ronald Hamowy (2 vols. [continuous pagination], Indianapolis: Liberty Fund, 1995), No. 69, p. 497.
17 Plutarch, Lives, intro. by John Dryden (5 vols., 1683), I, 195-6.
18 [Trenchard and Moyle], An Argument Shewing That A Standing Army Is Inconsistent With A Free Government (1697), reprinted in State Tracts (3 vols., 1714), III, p. 566.
19 Reprinted in Gwyn, Meaning of the Separation of Powers, p. 138. Trenchard used both clog and check: p. 140.
20 Moyle, The Whole Works (1727), 59. See Gwyn, Meaning, p. 88. On Moyle see Caroline Robbins, Two English Republican Tracts (Cambridge: Cambridge University Press, 1969).
21 Blair Worden, "Whig history and Puritan politics: the Memoirs of Edmund Ludlow revisited," Bulletin of the Institute of Historical Research 75 (2002), 209-37, at p. 222.
22 [Anon.], A Letter to A, B, C, D, E, F, etc. Concerning their Argument (1698), p. 13.
23 OED CD-Rom s.v. engineering.
24 The best discussion of the debates of 1697-1701 is the introduction to Jonathan Swift, A Discourse of the Contests and Dissentions between the Nobles and Commons in Athens and Rome (1701), ed. F.H. Ellis (Oxford: Clarendon Press, 1967); more recently Blair Worden has published a number of studies which transform our understanding of the politics of Toland and his associates, the most recent being "Whig history and Puritan politics: the Memoirs of Edmund Ludlow revisited".
25 [Trenchard and Moyle], Argument, ed. cit., 566.
26 Moyle, Whole Works, p. 53.
27 Cato's Letters, p. 461. In citing Cato's Letters and The Federalist I refer to the individual authors who we now know wrote individual sections, rather than to "Cato" (or Trenchard-and-Gordon) or "Publius" (or Madison-Jay-and-Hamilton).
28 Harrington, Political Works, 286, 834.
29 OED CD-Rom, s.v. system.
30 OED CD-Rom, s.v. constitution. J.H. Burns, "Bolingbroke and the Concept of Constitutional Government," Political Studies X (1962), 264-76. Dissertation, Letter X: Works (5 vols., London, 1744), vol. II, 130.
31 Dissertation, Letter XI: Works II, 157; Letter IX: Works II, 125.
32 Adam Smith, Essays on Philosophical Subjects, ed. I. S. Ross (Indianapolis: Liberty Fund, 1982), p. 66. See OED CD-Rom s.v. system, solar, Copernican.
33 David Hume, Essays, Moral, Political, and Literary, ed. E.F. Miller (Indianapolis: Liberty Classics, rev. ed. 1987), p. 273.
34 The Political Writings of John Adams, ed. George W. Carey (Washington, D.C.: Regnery, 2000), 647.
35 Sir James Steuart, An Inquiry into the Principles of Political Oeconomy, ed. A.S. Skinner (4 vols., Chicago: University of Chicago Press, 1998), vol. 2, p. 217; see also 278-9.
36 Kurt von Fritz, The Theory of the Mixed Constitution in Antiquity (New York: Columbia University Press, 1954), p. 365. (Quoted without demur in James M. Blythe, Ideal Government and the Mixed Constitution in the Middle Ages [Princeton: Princeton University Press, 1992], p. 27.)
37 F. W. Walbank, A Historical Commentary on Polybius (2 vols., Oxford: Clarendon Press, 1957), I, pp. 660-1.
38 Fragment de Polybe; et quelques extraits de Spelman sur la meilleure forme de Gouvernment possible (1789?), p. 27.
39 Polybius, The Histories, trans. W. R. Paton (6 vols., London: Heineman, 1923), III, p. 291.
40 Kenyon ed., Stuart Constitution, p. 21.
41 It is missing, for example, from the edition introduced by Dryden (1693), and translated by Sir Henry Shears, but does appear in the 1698 reprint, where the additions are described as translated by "another hand" (pace ESTC). Its relatively late date means, I think, that this translation of Polybius was not an important factor in the emergence of the new mechanical language. Ellis thinks that this translation was used by Swift (who quotes Polybius), on the grounds that Swift may have known Sir Henry Shears, who he mistakenly thinks is the translator of the whole text, but I see no reason to assume that Shears would have brought this second edition, in which he seems to have had no part, to Swift's attention, and Swift's own quotation suggests he was translating Polybius himself from either Latin or Greek.
42 Pargellis, "The Theory of Balanced Government," p. 45
43 The History of Polybious, trans. Edward Grimeston (1634), p. 287.
44 On Polybius, and classical learning in general, but with no mention of Plutarch, see Gilbert Chinard, "Polybius and the American Constitution," Journal of the History of Ideas 1 (1940), 38-58. I don't deny that Polybius was known - he is referred to by Milton, Moyle, Toland, and Swift - but his relative importance as compared to Plutarch needs assessment.
45 I quote from the 1676 edition, p. 36.
46 Moyle, Whole Works, p. 56.
47 On Moyle and the separation of powers see Gwyn, Separation, 87-8; Vile, Constitutionalism, while discussing Nedham, Bolingbroke, and Montesquieu, unfortunately contains no discussion of Moyle.
48 Harrington, Political Works, 196; OED CD-Rom, s.v. libration; Harrington, Political Works, 178 (an earlier use). The word occurs twice in Oceana, and from there it enters the debates of 1697-1701.
49 Harrington, Political Works, p. 341.
50 Cato's Letters, No. 61: ed. cit. p. 421.
51 Montesquieu, The Spirit of the Laws, trans. Anne M. Cohler et al (Cambridge: Cambridge University Press, 1989), p. 63.
52 Montesquieu, Spirit of the Laws, pp. 155-66.
53 Adams was the author of the Massachusetts constitution of 1780 (Political Writings, 498-551), which is often thought to provide the model for the "checks and balances" in the American constitution, and which perhaps best exemplifies what he was defending in 1787: see A. Hamilton, J. Jay, J. Madison, The Federalist, ed. G.W. Carey and J. McClellan (Indianapolis: Liberty Fund, 2001), xxx. There is no occurrence of the phrase "checks and balances" (or any equivalent) in Madison's notes on the Proceedings of the Federal Convention, although there are frequent references to checks, and occasional references to balances.
54 OED CD-Rom, s.v. check; Adams, Political Writings, p. 110; Friends of the Constitution: Writings of the "Other" Federalists, ed. C. A. Sheehan and G. L. McDowell (Indianapolis: Liberty Fund, 1998), p. 378; The Federalist, no. 9, p. 119; Isaac Kramnick's introduction to The Federalist (Harmondsworth: Penguin Books, 1987), pp. 64-5 - the edition I cite.
55 I was, at least, in the best company: see Bernard Bailyn, The Ideological Origins of the American Revolution (Cambridge, Mass.: Harvard University Press, 1967), p. 274.
56 The idea of an equilibrium was of central importance for Greek science: it is a key concept, for example, in Greek medicine.
57 Quoted in Kramnick's introduction, The Federalist, p. 63.
58 Harrington, Political Works, 249.
59 Quoted in Mayr, Authority, Liberty, p. 143.
60 Adams, Defence, ch. 4 (Political Writings, pp. 132-8); Gordon S. Wood, The Creation of the American Republic, 1776-1787 (Chapel Hill: University of North Carolina Press, 1969), p. 577 (which fails to identify the borrowing from Swift).
61 See Mayr, Authority, Liberty, p. 142.
62 Moyle, Whole Works, 51; A Letter to A, B, C, D, E, F, etc. Concerning their Argument (1698), p. 12.
63 Swift, Discourse, ed. Ellis, pp. 84-5. Quoted in Mayr, Authority, Liberty, p. 160; see Adams, Political Writings, p. 135.
64 Montesquieu, Esprit des lois (2 vols, Paris: Garnier, 1961), vol. 1, p. 172 (my translation: compare Cohler translation, p. 164).
65 American Political Writing During the Founding Era, ed. C. S. Hyneman and D. S. Lutz (2 vols., Indianapolis: Liberty Fund, 1983), p. 405 (and Adams, Political Writings, p. 486).
66 Montesquieu, Persian Letters, trans. C. J. Betts (Harmondsworth: Penguin Books, 1973), p. 187.
67 Bolingbroke, in The Craftsman, published separately in 1743 in Remarks on the History of England; Letter VII, Works I, p. 341. Quoted in Gwyn, Meaning, p. 95.
68 Quoted in Mayr, Authority, Liberty, p. 163; [Edward Spelman], A Fragment out of the Sixth Book of Polybius (London, 1743), note to p. 49.
69 I. Bernard Cohen, Science and the Founding Fathers (New York: W.W. Norton, 1995), p. 210.
70 Cohen, Science, pp. 204-10, 218-22.
71 Bernard Manin, "Checks, balances, and boundaries: the separation of powers in the constitutional debate of 1787," in B.-M. Fontana ed., The Invention of the Modern Republic (Cambridge: Cambridge University Press, 1994), 27-62, p. 59; Centinel in The Anti-Federalist, ed. Herbert J. Storing (Chicago: University of Chicago Press, 1985), p. 15; Adams (writing to Sherman in 1789), Political Writings, 449-50.
72 I leave aside a form of the balance which would have been familiar to anyone in the eighteenth century, the steelyard, on the grounds that it employs the principle of the lever to turn unequal weights into equal forces.
73 The literature on de Lolme is thin, but see Jean-Pierre Machelon, Les Idées Politiques de J.L. de Lolme (Paris: Presses Universitaires de France, 1969) and Mark Francis with John Morrow, "After the ancient constitution: Political theory and English constitutional writings, 1765-1832," History of Political Thought 9 (1988), 283-302.
74 De Lolme, Constitution, pp. 196, 203-4, 220, 322, 195
75 Federalist, no. 48, p. 309; no. 51, p. 320. See also Jefferson in 1789: "The tyranny of the legislatures is the most formidable dread at present, and will be for long years." (The Portable Thomas Jefferson, ed. Merrill D. Peterson (New York: Viking Penguin, 1975), 439-40.
76 The Writings and Speeches of Oliver Cromwell, ed. W.C. Abbott (4 vols., Cambridge, Mass.: Harvard University Press, 1937-47), vol. iv, p. 417. This is Burton's report of the speech; Morgan's version (p. 418) has "You are offended at a House of Lords. I tell you that unless you have some such thing as a balance you cannot be safe." For Cromwell's endorsement of Nedham's defence of the Instrument of Government see vol. Iii, p. 587. I owe these references to Blair Worden.
77 Moyle, Whole Works, 49, etc. The passage on p. 49-50 ('This wise lawgiver [Lycurgus] made such checks in the executive part of the government that in the administration they reciprocally controlled each other.') is a mystery. It appears, since it is in italics, to be a quotation, but comes, as far as I can see, neither from Herodotus nor Fletcher of Saltoun. If it is a quotation it would be good to know from what; but its appearance of being a quotation may well be (since the work was published posthumously) a misinterpretation of Moyle's manuscript. Trenchard, Short History of Standing Armies, 1698, p. vi; Gwyn, Meaning, p. 140. State Tracts, III, 638, 652. Justin Champion tells me Toland reprinted The Danger of Mercenary Parliaments in 1721/2 with a new preface for Molesworth's election campaign.
78 e.g. M. Nedham, The Excellencie of a Free State  (repr. London, 1767), pp. 5, 126-7 ('curb'), 65 ('bridle'). The 1767 reprint of Nedham's Excellencie of a Free State was widely known in America before the Revolution - more difficult, and more interesting, is the extent of Nedham's influence on the radical Whig tradition in the late seventeenth and early eighteenth centuries: see Worden, "Whig History", n. 58.
79 Moyle, Whole Works, 56-7; Gwyn, Meaning, p. 88.
80 Gwyn, Meaning, p. 98; Federalist, no. 58, p. 350.
81 Montesquieu, Esprit des lois (ed. cit.) vol. 1, pp. 169-72; De Lolme, Constitution, p. 405.
82 OED CD-Rom, s.v. responsibility. The word occurs frequently: Federalist, 370, 405-7, 435-6, 444.
83 Gunnar von Proschwitz, "Responsabilité: L'idée et le mot dans le débat politique du XVIIIe siècle," in Actes du Xe Congrès internationale de linguistique et philologie romane (1965), 385-97.
84 Unpublished paper by Vittoria Franco, "Individuo moderno, responsabilità, frantumazione delle gerarchie sociali."
85 OED CD-Rom, s.v. responsible. The need to make rulers accountable is a recurring theme of Nedham's, e.g. A True State of the Case of the Commonwealth  (repr. Exeter: The Rota, 1978), p. 38; Excellencie of a Free State, pp. 72-3.
86 Gwyn, Meaning, p. 141.
87 See quotation in Mayr, Authority, Liberty, p. 162.
88 OED CD-Rom, s.v. accountability.
89 Dissertation, Letter XVII: Works, II, 224.
90 De Lolme, Constitution, 291-305, 319-20, 427-8, 439. One may compare de Lolme with Hume, "Of the Liberty of the Press" (1741), particularly in its earlier version: David Hume, Essays Moral, Political and Literary, ed. Eugene F. Miller (rev. ed., Indianapolis: Liberty Fund, 1987), 9-13, 604-5.
91 A Letter to A, B, C, D, E, F, etc. Concerning their Argument (1698), 2; A true account of land forces in England (1699), 1-2; A Letter to His Most Excellent Majesty (1698), 633.
92 OED CD-Rom, s.v. clog; Mayr, Authority, Liberty, p. 161 (NB Mayr's inconsistency on the date of this text); "clog" already appears in close proximity to "check" in Trenchard: Gwyn, Meaning, p. 140.
93 Thomas Paine, Rights of Man, Common Sense and Other Political Writings, ed. Mark Philp (Oxford: Oxford University Press, 1995), pp. 9-10. On the importance of this passage, see Bailyn, Ideological Origins, pp. 285-6.
94 Wood, Creation, p. 224.
95 De Lolme, Constitution, pp. 218-228. The Instrument of Government provided a delay of twenty days between the passage of legislation and its taking effect, a provision defended by Nedham (A True State of the Case of the Commonwealth, p. 35) as providing time for reflection, while in
96 Wood, Creation, p. 239.
97 Adams, Works (**), IV, p. 390. [cross refs to Works in refs to Political Writings **]
98 Federalist, No. 63, p. 371; see Manin, "Checks," pp. 60-62.
99 Compare Spirit of the Laws, pp. 162, 182.
100 Manin, "Checks," pp. 30-31.
101 Nedham, A True State of the Case of the Commonwealth, pp. 10, 33; the word check also occurs on p. 22, in the context of a discussion of the danger of an executive power "without check or controll."
102 [Toland], Art of Governing by Partys (1701), 31. It is possible that Toland is the source of later usages of "checks and balances": this work was twice reprinted (c. 1757, c. 1760). For an example of Trenchard using check and balance in close proximity and as synonyms, see below, p. ** .
103 Spelman, Fragment, p. iv.
104 Quoted in Pargellis, "Theory," pp. 47-8.
105 Quoted in Paul Rahe, Republics Ancient and Modern (Chapel Hill: University of North Carolina Press, 1992), pp. 562-3.
106 Cohen, Science, 225-6.
107 Dissertation, Letter XVII: Works, II, 224.
108 Anti-Federalist, ed. Storing, p. 15.
109 There was an unauthorised reprint of Spelman's Fragment in 1747 under the title Polybius's Glorious Discourse, and an authorised reprint in an appendix to vol. 1 of Spelman's 4 vol. edition of Dionysius of Halicarnassus (1758). Adams reproduces lengthy passages from Spelman's translation of Polybius in the Defence, Works, IV, pp. 435-9; he also reproduces passages from Spelman's translation of Dionysius. Spelman's preface, but not his translation, were reproduced in the French Revolutionary text Fragment de Polybe. Selections from Spelman are reproduced in J.A.W. Gunn ed., Factions No More (London: Frank Cass, 1972), 151-3 and in Peter Campbell, "An Early Defence of Party", Political Studies, III, 166-7. On Spelman see A. Momigliano, "Polybius Between the English and the Turks" (1974), in Momigliano, Sesto contributo alla storia degli studi classici e del mondo antico (2 vols., Rome: Edizione di storia e letteratura, 1980), 125-41; Caroline Robbins, "'Discordant Parties', a study of the acceptance of party by Englishmen", Political Science Quarterly 73 (1958), 505-29: 527.
110 See, for example, Nedham, Excellencie, p. 160: "Now that you may know what faction is, and which is the factious party in any state of kingdom, afflicted with that infirmity; the only way is first to find out the true and declared interest of state; and then if you observe any designs, counsels, actings, or persons, moving in opposition to that which is the true public interest, it may be infallibly concluded that there lies the faction, and the factious party."
111 Spelman, Fragment, v-viii.
112 De Lolme, Constitution, pp. 206-13; see also pp. 271-80.
113 Plutarch, Lives, introd. Dryden (1683), I, 141-2.
114 Cato's Letters, No. 70, p. 504. Compare Nedham, in A True State of the Case of the Commonwealth, p. 36, arguing the need for frequent elections: "And how unapt men are of their own accord to part with such power, when they have got it once into their hands, how apt they are to corrupt like standing Pools, and contract an arbitrary distemper in execution of Law, and what miserable inconveniences must follow thereupon, we, and all the people of the Land can tell be too sad experience."
115 Jean Louis de Lolme, The Constitution of England (rev. ed., London: Robinson and Murray, 1789), pp. 533-4.
116 Anti-Federalist, ed. Storing, p. 15.
117 In other words, they would have read Polybius as if corrected along the lines proposed by Moyle: see his An Essay Upon the Constitution of the Roman Government in Robbins, Two Republican Tracts, p. 231.
118 An Argument, in State Tracts, III, 565.
119 The Federalist Papers, no. 48, pp. 309, 312; no. 73, p. 418; Storing, Anti-Federalist, p. 319.
120 Cato's Letters, No. 116, p. 814. There are certainly connections to be made between systems analysis, the mechanical philosophy, and materialism: a valuable starting point is provided by Harold J. Cook, "Body and Passions: Materialism and the Early Modern State", in Osiris 17 (2002), 25-48, but it is worth remembering that one could be a mechanist and materialist without wanting a complex state system - one need think only of Helvétius.
121 Arnold Geulincx, Ethics, tr. 1, ch. 2 (**trans. J. Cottingham, p. 211). (? in John Cottingham ed., Western Philosophy: An Anthology (Oxford: Blackwell, 1996)**)
122 OED CD-Rom, s.v. regular.
123 See Mayr, Authority, Liberty, and also Mayr, The Origins of Feedback Control (Cambridge, Mass.: MIT Press, 1970).
124 OED CD-Rom, s.v. self-governed.
125 Thus Nedham is careful to insist that frequent elections are not enough, but must be accompanied by term limits: Excellencie, 42-3, 60-1, 76-7, 107-9.
126 Thus Nedham insists that all citizens should know the principles of liberty, and attacks the Venetian constitution as tyrannical; nevertheless he recommends that all debates of the senate should be held in secret: Excellencie, pp. xvi, 31-2, 103-5, 138-9.
127 De Lolme, Constitution, p. 259
128 De Lolme, Constitution, pp. 448-50. The earliest direct comparison between a constitutional mechanism (in this case a form of bicameralism) and a self-regulating machine that I know is in Sieyès. "Sur l'organisation du pouvoir législatif et la sanction royale" (7 Sept. 1789), in Orateurs de la Révolution française, vol. 1, Les Constituants, ed. F. Furet and R. Halévi (Paris: Gallimard, 1989), p. 1033: "Je ne vois pas, en effet, pourquoi, si l'exercice d'un veto suspensif est bon et utile, on le sortirait de la place que la nature des choses lui a destinée dans la législature elle-même. Le premier qui, en mécanique, fit usage du régulateur, se garda bien de la placer hors de la machine don't il voulait modérer le mouvement trop précipité."
129 "Life of John Adams" (in Works **), p. 625
130 See interview with Ignatief **.
131 Bolingbroke's influence in America is stressed in Bailyn, Ideological Origins; for Hume and The Federalist see Wills, Explaining America and Douglass Adair, Fame and the Founding Fathers (Indianapolis: Liberty Fund, 1998).
132 Cato's Letters, no. 70, p. 504 (Gordon's words).
133 Cato's Letters, no. 60, p. 416-7. See also Adam Ferguson, An Essay on the History of Civil Society [1767, rev. ed. of 1773] (Farnborough, Hants.: Gregg International, 1969), pp. 214 ("Liberty is maintained by the continued differences and oppositions of numbers, not by their concurring zeal in behalf of equitable government") and 268 ("to prevent the practice of crimes, by balancing against each other the selfish and partial dispositions of men").
134 Manin, "Checks," pp. 57-8.
135 Adams, Works, IV, p. 358.
136 Federalist, no. 70, p. 407. Hamilton's No. 9, p. 119, which includes the phrase "legislative balances and checks" reads to me like a summary of De Lolme.
137 De Lolme, Constitution, p. 247.
138 Federalist, no. 55, p. 336.
139 De Lolme, Constitution, pp. 256-8.
140 De Lolme, Constitution, pp. 271, 276.
141 Hume, like de Lolme, thought the representative assembly needed to be weakened and the executive strengthened; but he was happy to see both objectives attained through corruption.
142 Federalist, no. 49, p. 318. The extensive discussion of party in Wills's Explaining America contains no hint that Madison ever wrote a sentence comparable to this one.
143 This phrase originates with de Tocqueville's Democracy in America, translated into English in 1835, though the first usage given by the OED is from Mill's On Liberty (1859). Classical and Renaissance views that are similar but not identical to the concept of majority tyranny are collected by Nedham in his attack on the Levellers: Marchamont Nedham, The Case of the Commonwealth of England Stated , ed. Philip A. Knachel (Charlottesville: University of Press of Virginia, 1969), 99-101. Nedham's Excellencie of a Free State, with the self-perpetuating Rump Parliament in mind, insists that a representative assembly can easily become tyrannical, particularly when it is not held to account through frequent elections (pp. 96-101).
144 Adams, Works, IV, p. 358. Vibration had been used as a technical term by Sir James Steuart for the process by which a market moves about an equilibrium position: e.g. Inquiry, II, p. 146.
145 ref. Constant **. In making this claim I part company, I think, with Paul Rahe's indispensable Republics Ancient and Modern, which sees modern republicanism as largely complete with Harrington.
146 Federalist, no. 14, p. 141.
147 The passage appears to be a quotation from Trenchard's and Moyle's Argument in An argument shewing that a standing army with consent of parliament is not inconsistent with a free government (1698), p. 14, but I cannot find it there. It is to be found in a contemporary work by an author linked to them, Fletcher of Saltoun's Discourse of Government with Relation to Militias (1698): see his Political Works (1732), p. 9.
148 Bolingbroke, Dissertation Letter XIII: Works, II, 177.
149 Skinner, Liberty Before Liberalism.
150 Cato's Letters, No. 62, p. 427.
151 OED CD-Rom s.v. majority.
152 OED CD-Rom s.v. minority. The classic text on consensus politics is Mark Kishlansky, "The emergence of adversary politics," Journal of Modern History 49 (1977), 617-40..
153 Cato's Letters, No. 115, pp. 803-5.
154 Adams, Political Writings, 494 (Letter to John Penn, 1776).
155 Notes on the State of Virginia, in The Portable Thomas Jefferson, p. 164.
156 Nedham, Excellencie, p. 134-5; see also pp. 18-19 on "the lust of mankind after dominion" and pp. 147-53 on the separation of powers. For a classical text which comes near to expressing the view that power corrupts, see Plutarch, "Sallust", in Fall of the Roman Republic, trans. Rex Warner (rev. ed., Harmondsworth: Penguin, 1972), p. 104.
157 D. Wootton, "From Commonwealth to Common Sense", in Wootton ed., Republicanism, Liberty, and Commercial Society (Stanford: Stanford University Press, 1994), 1-41, p. 18, entirely misses the point which now seems to me crucial.
158 Moyle, Whole Works, p. 58.
159 See Morton While, Philosophy, "The Federalist", and the Constitution (New York: Oxford University Press, 1987), part 2: "The different legacies of Locke and Hume".
160 Argument, p. 566.