Aristotle of Stagira was a Greek philosopher, logician, and scientist and one of the most influential ancient thinkers. As a young man, Aristotle entered Plato’s Academy in Athens, where he studied for 20 years. Subsequently, he was invited by Philip of Macedon to tutor his son, the future Alexander the Great. Aristotle later returned to Athens to found his own school, the Lyceum, and write some of his most important treatises. After Alexander’s sudden death, Aristotle had to flee Athens because of his Macedonian affiliation, and he died soon after. Although many of his writings are lost, a substantial corpus survives, consisting of treatises probably compiled from his lecture notes. These works influenced Roman, Byzantine, Arab, and Jewish philosophers, and their rediscovery in Western Europe during the Middle Ages triggered the rise of scholasticism and contributed to the rise of modern science.

Aristotle’s philosophical system consists of numerous specialized sciences. He holds that each science must be adapted to its own subject matter with distinctive problems, methods, and first principles. All the sciences presuppose a theory of logic, language, and knowledge, which Aristotle set forth in a set of treatises called the Organon. These common elements include a system of syllogistic logic that prevailed largely unchallenged until the 20th century. Aristotle formulated and defended the law of noncontradiction and the principle of identity, and he maintained (against his teacher Plato) that knowledge must be based on sense perception, that reality ultimately consisted of individual substances, and that substances belonged to natural kinds (e.g., human being or horse) with distinctive natural ends or functions. Aristotle distinguished three branches of science: (1) The theoretical (contemplative) sciences were devoted to knowledge or truth for its own sake. These sciences included the natural sciences (corresponding to physics, chemistry, biology, and psychology), mathematics, and metaphysics (the study of being qua being, culminating in theology). (2) The practical sciences (e.g., ethics, politics, and economics) are concerned with human action (praxis). (3) The productive sciences aim at some product, either useful (e.g., architecture or medicine) or imitative (e.g., poetry).

Aristotle’s practical treatise, the Nicomachean Ethics, argues that the human good consists of happiness, understood as rational and virtuous activity; that moral virtue involves achieving a mean (or intermediate condition) between extremes (e.g., courage is a mean between cowardice and foolhardiness); and that this mean is attained through practical wisdom, a deliberative excellence cognizant of the human end. Although concerned with individual excellence, the Ethics describes itself as a work of “political science.” The basis for this self‐​description is evident from Aristotle’s Politics, which begins by arguing that human beings are by nature political animals, that the city‐​state (or polis) exists by nature, and that the city‐​state is prior by nature to individual human beings. Because the city‐​state is necessary for individual human perfection, ethics is a part of political philosophy.

Although the city‐​state represents, in Aristotle’s view, the outgrowth and perfection of human nature, it also requires a lawgiver whose function it is to apply the science of politics in order to fashion a constitution, laws, and system of education for the citizens. The Politics expounds this theory, distinguishing between just constitutions that promote the common advantage of all citizens and unjust constitutions that seek the private advantage of the ruling class. The best constitution will assign political rights on the basis of civic virtue. Aristotle described a constitution that fulfills this ideal, including a system of public education aimed at producing virtuous citizens. He also discussed how political science should address problems of political change, revolution, and faction. Aristotle viewed revolution as a disease of the city‐​state that has injustice as its leading cause: The ruled become rebellious when they perceive the rulers treating them unjustly. Aristotle offered political remedies based on this analysis.

Aristotle’s overall political position was conservative rather than libertarian. He held that social order must always be imposed by a single ruling element, so that he tended to favor authoritarian systems. He deprecated the view, which was popular among the democrats of his day, that freedom consisted of living as one wishes. Instead, from his perspective, freedom was the right to do what one should do. He advocated compulsory public moral education, and he endorsed the rule of men over women and of free persons over “natural” slaves.

Yet he also contributed to libertarian theory, especially through his theory of political justice. He criticized Plato’s collectivist ideal, arguing that the best constitution promotes the interests of each and every citizen—and, hence, protects individual rights. Aristotle’s constitutional theory also had an indirect, but important, influence on European classical liberals and on the founders of the American constitution. Indeed, some recent American libertarian political theorists explicitly acknowledge their debt to Aristotle.

Further Readings

Barnes, Jonathan, ed. The Complete Works of Aristotle. 2 vols. Princeton, NJ: Princeton University Press, 1984.

Keyt, David, and Miller, Fred D., Jr. A Companion to Aristotle’s Politics. Oxford: Blackwell, 1991.

Miller, Fred D., Jr., Nature, Justice, and Rights in Aristotle’s Politics. Oxford: Oxford University Press, 1955.

Newman, W. L., ed. The Politics of Aristotle. 4 vols. Oxford: Oxford University Press, 1887–1902.

Rasmussen, Douglas B., and Den Uyl, Douglas J. Liberty and Nature: An Aristotelian Defense of Liberal Order. LaSalle, IL: Open Court Publishing, 1991.

Shields, Christopher. Aristotle. London: Routledge, 2007.

Polybius and the Origins of the Separation of Powers, written by Paul Meany

Originally published
Read More
Read Less