At least three fundamental aspects of the United States Congress can be traced to ancient historical examples and political philosophy: representative democracy, bicameralism, and separation of powers. The challenge to the framers of the Constitution was to adapt those concepts to the American experience.
The earliest forms of democratic government began in the city-states of Ancient Greece. Those included a mixture of direct participation of citizens in an assembly and a representative council chosen by lot. Participation, representation, and decision making ideally conformed to the concept of classical republicanism—citizens and their representatives should be educated, virtuous, and engaged in public affairs. Republican government could work in a small community of homogenous people who could deliberate over the common good. The virtues of the classical republican citizen and representative were espoused by Aristotle (384-322 BC) in his book The Politics. Ancient Rome provided another example of a republic, and the concept of classical republicanism was further developed by Cicero (106-43 BC), a statesman and a scholar at the end of the Roman Republic.
The framers also knew the British Parliament as a representative body. The British Parliament evolved from assemblies of nobles who advised the monarch about important matters. By the thirteenth century, and particularly after Magna Carta in 1215—the monarchs ceded significant authority, particularly over matters of taxation, to the nobles, clergy, landed gentry, and local officials who served as a check on the powers of the kings and queens. Parliament gradually gained independent power, and by the seventeenth century had dramatically curtailed the power of the monarchs to influence law making. This is the Parliament that was familiar to the framers of the American Constitution.
The general concept of bicameralism can also be traced from ancient governments to the American colonies. Athens, Sparta, Crete, Carthage, and early Rome had representative assemblies of different classes of people and councils of elders. Madison explains the necessary function of a senate and the distinction between ancient republics and the American Congress in Federalist, No. 63. “Long lived” republics, such as Sparta, Rome, and Carthage had senates. The British Parliament, with its House of Commons and House of Lords, constituted another example of bicameralism. And, most of the state governments at the time of the Founding had bicameral legislatures.
Madison argued that bicameralism played a critical role in tempering the potential for abusive legislative power. History provided “very instructive proofs of the necessity of some institution that will blend stability with liberty.” (Federalist, No. 63) Thus, a “well-constructed Senate” can serve as a check in popular or “free” governments in “particular moments in public affairs when the people, stimulated by some irregular passion, or some illicit advantage, or misled by the artful misrepresentations of interested men, may call for measures which they themselves will afterward be the most ready to lament and condemn.” (Federalist, No. 63)
Separation of Powers
Several ancient constitutions in Greece and the Roman Republic had a separation of powers. Eighteen century French philosopher Baron de Montesquieu traces the doctrine of separation of powers to Aristotle. In The Politics, Aristotle established the principle that all governments should have three functions: “the deliberative, the magisterial, and the judicative” which coincide, respectively, with the legislative (law-making), executive (law-enforcing) and judicial (law interpreting) functions of government. Yet Aristotle did not advocate the separation of those powers. Montesquieu elaborated on this framework in the Spirit of Laws, by explaining the practical purpose of separating the powers of government.
When the legislative and executive powers are united in the same person, or in the same body of magistrates, there can be no liberty… Again, there is no liberty, if the judiciary power be not separated from the legislative and executive. Were it joined with the legislative, the life and liberty of the subject would be exposed to arbitrary control; for the judge would then be the legislator. Were it joined to the executive power, the judge might behave with violence and oppression. There would be an end to everything, were the same man, or the same body, whether of the nobles or of the people, to exercise those three powers, that of enacting laws, that of executing the public resolutions, and of trying the causes of individuals. (Montesquieu 1748, Book 11, Chapter 6)
Madison similarly emphasized the necessity of separation of powers in Federalist, No. 47: “The accumulation of all powers, the legislative, executive, and judiciary, in the same hands, whether of one, the few, or the many, and whether hereditary, self-appointed, or elective, may justly be pronounced the very definition of tyranny.” He refers to Montesquieu as “the oracle who is always consulted and cited on this subject.” (Federalist, No. 47)