Contents Index


Aristotle, 384-322 BCE, Greek philosopher.

Aristotle's father was a physician, from whom he caught an interest in anatomy and biology. In 367, he attended Plato's Academy in Athens, wher he later became a teacher. He entered the service of Philip of Macedonia in 343 as tutor to his young son Alexander, later known as Alexander the Great. In 335, he founded the Lyceum (or Peripatus), his own Athenian academy with greater concern for the natural world than was common in Plato's Academy.

The greatest part of Aristotle's writings do not survive, but the remaining works have been among the most influential in subsequent though in a number of disciplines. The tremendous range of his work is evident from the titles of some of his most important surviving works: the Physics; On the Heavens (on astronomy); the Meteorology; the History of Animals; the Parts of Animals; the Generation of Animals (where he inquired into the origin of life by asking whether the embryo always existed or whether it was brought into being by the reproductive process); the Prior and Posterior Analytics (treatises on logic); the Metaphysics; On the Soul; the Moralia; the Ethics; the Politics; the Poetics (one of the first systematic surveys of literary criticism); the Rhetoric; and the Constitution of Athens.

Most of Aristotle's works -- including, but not limited to, the biological ones -- proceed by classification and taxonomy of ideas, and one of his recurring arguments is that the form (of, for instance, an animal) is determined by its ultimate function, or telos. This teleology pervades not only his scientific works but his logical, metaphysical, and ethical treatises as well. His Nichomachean Ethics, for instance, asserts that virtue is that which tends toward the greatest good: a rational principle that consists in the pursuit of a middle path and the avoidance of extremes.