Ancient Philosophy was almost entirely Greek. The greatest philosophers of the ancient world were three Greeks of the 400’s and 300’s B.C.–Socrates, Plato, and Aristotle. Their philosophy influenced all later Western culture. Our ideas in the fields of metaphysics, science, logic, and ethics originated from their thought. A number of distinctive schools of philosophy also flourished in ancient Greece.
The Pre-Socratics were the first Greek philosophers. Their name comes from the fact that most of them lived before the birth of Socrates, which was about 469 B.C. The pre-Socratic philosophers were mainly interested in the nature and source of the universe and the nature of reality. They wanted to identify the fundamental substance that they thought underlay all phenomena, and in terms of which all phenomena could be explained.
Unlike most other people of their time, the pre-Socratic philosophers did not believe that gods or supernatural forces caused natural events. Instead, they sought a natural explanation for natural phenomena. The philosophers saw the universe as a set of connected and unified phenomena for which thought could find an explanation. They gave many different and conflicting answers to basic philosophic questions. However, the importance of the pre-Socratics lies not in the truth of their answers but in the fact that they examined the questions in the first place. They had no philosophic tradition to work from, but their ideas provided a tradition for all later philosophers.
Socrates left no writings, though he was constantly engaged in philosophic discussion. Our knowledge of his ideas and methods comes mainly from dialogues written by his pupil Plato. In most of the dialogues, Socrates appears as the main character, who leads and develops the process of inquiry.
Socrates lived in Athens and taught in the streets, market place, and gymnasiums. He taught by a question-and-answer method. Socrates tried to get a definition or precise view of some abstract idea, such as knowledge, virtue, justice, or wisdom. He would use close, sharp questioning, constantly asking “What do you mean?” and “How do you know?” This procedure, called the Socratic method, became the model for philosophic methods that emphasize debate and discussion.
Socrates wanted to replace vague opinions with clear ideas. He often questioned important Athenians and exposed their empty claims to knowledge and wisdom. This practice made him many enemies, and he was put to death as a danger to the state. He thus became a symbol of the philosopher who pursued an argument wherever it led to arrive at the truth, no matter what the cost.
Plato believed that we cannot gain knowledge of things through our senses because the objects of sense perception are fleeting and constantly changing. Plato stated that we can have genuine knowledge only of changeless things, such as truth, beauty, and goodness, which are known by the mind. He called such things ideas or forms.
Plato taught that only ideas are real and that all other things only reflect ideas. This view became known as idealism. According to Plato, the most important idea is the idea of good. Knowledge of good is the object of all inquiry, a goal to which all other things are subordinate. Plato stated that the best life is one of contemplation of eternal truths. However, he believed people who have attained this state must return to the world of everyday life and use their skills and knowledge to serve humanity. Plato also believed that the soul is immortal and that only the body perishes at death. His ideas contributed to views about the body, soul, and eternal things later developed in Christian theology.
Aristotle, Plato’s greatest pupil, wrote about almost every known subject of his day. He invented the idea of a science and of separate sciences, each having distinct principles and dealing with different subject matter. He wrote on such topics as physics, astronomy, psychology, biology, physiology, and anatomy. Aristotle also investigated what he called “first philosophy,” later known as metaphysics.
Aristotle created the earliest philosophic system. In his philosophy, all branches of inquiry and knowledge are parts of some overall system and connected by the same concepts and principles. Aristotle believed that all things in nature have some purpose. According to his philosophy, the nature of each thing is determined by its purpose, and all things seek to fulfill their natures by carrying out these purposes.
Aristotle’s basic method of inquiry consisted of starting from what we know or think we know and then asking how, what, and why. In his metaphysics, he developed the idea of a first cause, which was not itself caused by anything, as the ultimate explanation of existence. Christian theologians later adopted this idea as a basic argument for the existence of God. Aristotle taught that everyone aims at some good. He said that happiness does not lie in pleasure but in virtuous activity. By virtuous activity, he meant behaving according to a mean between extremes. For example, courage is the mean between the extremes of cowardice and foolhardiness. The highest happiness of all, Aristotle believed, was the contemplative use of the mind.
Stoic Philosophy and Epicureanism were the two main schools of Greek philosophy that emerged after the death of Aristotle in 322 B.C. Both schools taught that the purpose of knowing is to enable a person to lead the best and most contented life.
Stoic philosophy was founded by Zeno of Citium. He taught that people should spend their lives trying to cultivate virtue, the greatest good. The Stoics believed in strict determinism–the idea that all things are fated to be. Therefore, they said, a wise and virtuous person accepts and makes the best of what cannot be changed. Stoicism spread to Rome. There, the chief Stoics included the statesman Marcus Tullius Cicero, the emperor Marcus Aurelius, and the teacher Epictetus.
Epicureanism was founded by Epicurus. Epicurus based his philosophy on hedonism–the idea that the only good in life is pleasure. However, Epicurus taught that not all pleasures are good. The only good pleasures are calm and moderate ones because extreme pleasures could lead to pain. The highest pleasures, Epicurus said, are physical health and peace of mind, two kinds of freedom from pain.
Skepticism was a school of philosophy founded by Pyrrho of Elis about the same time that Stoic philosophy and Epicureanism flourished. Pyrrho taught that we can know nothing. Our senses, he said, deceive us and provide no accurate knowledge of the way things are. Thus, all claims to knowledge are false. Because we can know nothing, in this view, we should treat all things with indifference and make no judgments.
Neoplatonism was a revived version of some of Plato’s ideas as adapted by Plotinus, a philosopher who may have been born in Egypt in the A.D. 200’s. Neoplatonism tried to guide the individual toward a unity–a oneness–with God, which is a state of blessedness. Plotinus believed that the human soul yearns for reunion with God, which it can achieve only in mystical experience. Neoplatonism provided the bridge between Greek philosophy and early Christian philosophy. It inspired the idea that important truths can be learned only through faith and God’s influence, not by reason.