Aristotle

Perhaps the most famous figure in the history of philosophy, Aristotle (384–322 B.C.) was an enormously influential Greek philosopher who addressed a wide variety of philosophical issues such as aesthetics, biology, epistemology, ethics, logic, metaphysics, politics, and psychology.

At age 17, Aristotle came to Athens from Macedonia to study at Plato’s Academy where Aristotle studied for twenty years. Although respectful to Plato and his ideas, Aristotle would eventually contradict the philosophy of Plato in several major ways. In 342 B.C., Aristotle began tutoring Alexander the Great. In 335, Aristotle founded his own school in Athens called the Lyceum where he brought together a large group of brilliant research students. A sign above the Lyceum read, “Let No One Ignorant of Geometry Enter Therein.” In 323, Alexander the Great died and charges of impiety were brought against Aristotle. To save Athens from “sinning twice” (Athens put Socrates to death) he fled the city.

Aristotle wrote a tremendous amount of literature—about four hundred books in all. Unfortunately, 80% of what he wrote has been lost. Still, one million words survived—twice the amount of what we have of Plato’s writings.

Aristotle is known as the “Father of Logic” because he created the syllogism and developed the study of deductive logic. Unlike his predecessor, Plato, who claimed that reality is based primarily in metaphysical “forms” or “ideas” that exist outside of our earthly realm, Aristotle said reality is based in individual earthly substances. Thus, Aristotle replaced Plato’s forms with universals—common qualities the mind can grasp in the physical world that do not exist independently of the physical world. For Aristotle, logic and empiricism were the foundation of knowledge.

In the realm of metaphysics, Aristotle is known for his concept of the “Prime Mover.” According to Aristotle, all motion is the result of something. Since the universe is in motion, there must be some Prime Mover who caused the universe to exist. Although Aristotle’s Prime Mover is not the Christian God, Christian philosophers such as Thomas Aquinas (A.D. 1225–74) would claim Aristotle’s theory as support for the view that a supreme being caused the world to exist. 

In regard to the soul, Aristotle argued that the soul is essentially linked to the body and is not just some spiritual substance that is imprisoned in the body as many Greeks including Socrates believed. The function of the soul is to help the intellectual and moral aspects of a person. As to ethics, Aristotle asserted that human happiness means living in conformity with nature.

Aristotle’s influence on the Western world was largely lost with the fall of the Roman Empire. In the ninth century, though, Arab scholars introduced Aristotle’s works to the Islamic world. In the thirteenth century, Christian theologians rediscovered Aristotle. At first, the Catholic Church initially condemned his works but scholars from the University of Paris and Thomas Aquinas relied heavily on his works. Soon Aristotle’s works were viewed as the highest achievement of human reason apart from the revelation of the Bible.