Greek Philosopher Plato

The philosophy of Plato has probably had more influence on Western thought than that of any other man. Another great Greek philosopher, Aristotle, was a student of Plato and was strongly influenced by him.

Plato's writings encompass the whole field of philosophy, and he also wrote on politics, education, and law. His work was the basis of Neoplatonism, a school of philosophy that flourished in the 3d century A.D. and that was a major influence on St. Augustine and other early Christian philosophers. Plato was also the founder of the Academy in Athens. It was the most influential school in the Western world and was in existence for almost a thousand years.

Plato's idealism, which holds that true knowledge of reality comes from the world of ideas, rather than from everyday experience, has been defended or attacked by virtually every philosopher who followed him. Because Aristotle placed more stress on knowledge derived from the senses, it is sometimes said that every philosopher is either a Platonist or an Aristotelian, in recognition of the philosophical positions held by Plato and his most famous student.


Plato lived during the period of Athens' decline as the cultural and political capital of the Greek world. He was born about two years after the death of Pericles, who ruled Athens during its golden age. The Peloponnesian War, which began about four years before Plato's birth, was a long and bloody struggle that finally reduced the once-proud Athenian democracy to tyranny and despotism.

Aristocles, which was Plato's real name, was born into a wealthy aristocratic family. As a youth he was a splendid athlete, and his nickname, "Plato", means, roughly, "broad-shouldered".

From his letters it is known that he had an early ambition to enter public life. However, disillusionment with the various ruling groups in Athens caused him to turn to writing and teaching instead.

Plato was a student of the philosopher Socrates, who in 399 B.C. was arrested by the Athenian government and charged with impiety. He was tried, convicted, and condemned to death. The death of Socrates made a lasting impression on Plato. He left Athens and traveled extensively, visiting various Greek cities around the Mediterranean.

Plato eventually returned to Athens and founded the Academy in about 387 B.C. He spent the rest of his life teaching and writing. Twice, however, he went to Syracuse to tutor its young king, Dionysius the Younger. Because of political intrigue, Plato was forced to leave the city both times, and once he barely escaped with his life. He died in Athens at the age of 80 or 81.


Plato wrote in the literary form of the dialogue, which consists of conversations between two or more persons. The dialogue form allowed Plato to develop character, build suspense, and add touches of humor and irony. He was a superb literary artist, and his works can be read for their literary value alone.

The early dialogues, written from about the time of Socrates' death to 387 B.C., emphasize ethical questions. The middle dialogues, written from the time of the founding of the Academy until about 360 B.C., contain Plato's most important writings on metaphysics and epistemology. The later dialogues tend to be concerned with logic, mathematics, the law, and natural science.

In the early and middle dialogues, Socrates is usually the leading character. The dialogues generally open with one of Socrates' followers asking him a question, such as "What is justice?" Pretending not to know the answer, Socrates questions his followers, getting their opinions, pointing out their faulty reasoning, and finally leading the student who originally asked the question to arrive at a satisfactory answer. Plato's early dialogues are probably an accurate rendering of the method Socrates used and probably reflect Socrates' philosophy as well. In the later dialogues, however, Socrates is less prominent, both as a character and as the spokesman for Plato's philosophy. In the last dialogue, the Laws, Socrates does not appear at all.

Plato's Philosophy

Plato's doctrine of Ideas is the core of his whole philosophy and the foundation for his epistemology, or theory of knowledge, his metaphysics, or theory of the meaning of existence, and his ethical and political theories.

According to Plato the human senses are undepend-able sources of knowledge. They sometimes give false impressions of the physical world. For example, one's eyes may reveal that a building is orange, when in fact it only appears so because it is reflecting the rays of the setting sun. Sense impressions are also misleading because they are often incapable of transmitting the changes that take place constantly in the physical world. For example, scientific studies reveal that over a long period of time, mountain ranges rise, erode, and flatten out again. The senses of one human being are not able to detect these gradual changes, however, and to the human eye a mountain is permanent.

However, man does not depend solely on his senses. He is able to subject his sense perceptions to a critical examination, because he also has the faculty of reason. By applying reason, he can gain knowledge of reality, which is the world of pure Forms or Ideas. Man's reason, and hence his knowledge of the world of pure Forms, is imperfect and faulty, just as the physical world is an imperfect and faulty copy of the world of Ideas. For example, there is no completely just society on earth, but the Idea of justice exists as a pure Form. To the extent that man is able to comprehend the Idea of justice, he recognizes the imperfection of justice in the everyday world. By using his knowledge of the world of Ideas, man is able to examine and sometimes to discard information received through the senses.

The world of Ideas is permanent and unchanging. The Idea of the Good, or God, is the unifying principle of the realm of Ideas. God constitutes total reason and goodness and is the ultimate cause of both the world of Ideas and of the physical world.

Later philosophers have tended to treat metaphysics, ethics, and epistemology as separate problems. For Plato, however, they are so closely connected that he rarely discusses one of them without considering the others. The Republic, for example, is primarily an attempt to define justice, an ethical ideal, and to show how it can be encouraged by the creation of an ideal political system. To define justice, however, Plato must establish the essential nature and purpose of man. These are metaphysical issues. Knowledge itself has to be denned in order for man to distinguish between reality, which is made known to man through his reason, and appearance, which is conveyed to man by the senses.

The Parable of the Cave

A famous parable in the Republic illustrates Plato's ability to deal with several philosophical issues at once. The parable compares mankind's condition to that of a group of prisoners chained in a dark cave. The only things of the external world they can see are shadows thrown against a wall from outside the cave. Because they have never seen the real figures that are casting the shadows, they mistakenly believe that the shadows themselves are real.

If one of the prisoners should be allowed to leave the cave, he would realize that the figures walking back and forth, not the shadows they make, are real. He would also be able to contemplate the sun, realizing that it is the source of all light and life. If forced to reenter the cave, he would have only pity for the ignorant beliefs of the other inmates. However, any attempt to inform them of the true nature of reality would be met with ridicule and contempt.

The parable can be interpreted as a metaphysical statement on the nature of reality versus appearance. The reflected shadows on the cave wall are physical phenomena, which are only appearance. The actual figures walking outside the cave are the Platonic Ideas. The sun, as the source of all light and life, can be compared to the Idea of the Good, or God.

The parable may also be given an epistemological interpretation. The eyes of the prisoners, representing the senses in general, are deceiving, because they are incapable of distinguishing appearance from reality. The parable implies that true knowledge comes only from a direct encounter with the light, which may be compared to the rational principles on which the universe is founded. The fact that the prisoner returning to the cave is unable to convince the other inmates of the existence of the real world indicates that each man must exercise his own rational faculties to gain knowledge.

Finally, the parable has an ethical meaning. The Good can be achieved only by knowledge. Evil results from ignorance, from mistaking appearance for reality. The man who has seen the truth has no desire to reenter the cave of ignorance.

The Ideal State

The parable also justifies the class structure of the ideal state created in the Republic. Plato's ideal republic consists of three classes. The highest is the ruling class, comprising the wisest men in the society. They rule by rational principles. Their authority to rule the other classes rests on their knowledge of the truth. Plato's ideal republic also has a military class, whose function is to protect the state, and a worker class, composed of artisans, laborers, and men of commerce and trade. Their function is to provide the material things required by the society and perform the necessary menial tasks.

Plato believed that greed is the origin of many of the evils in society. He specified that the ruling and military classes should not own property and should not even be allowed to handle money. They were to lead austere lives, separated from the worker class.

The education of the young was to be placed completely in the hands of the state, and infants would be taken from their mothers and reared by the state. The arts would be strictly controlled, and only patriotic and morally uplifting works would be permitted.

Plato's republic has often been criticized as harsh and inhuman. In modern times it has been compared to 20th-century examples of Fascist and other totalitarian regimes. There are important differences, however. The rulers in Plato's republic occupy their position because they are the wisest and most virtuous men in the society. The existence of these men was an absolute requirement for the republic, and Plato realized that a society lacking such men to lead it could never approach his ideal.

The Soul

Plato believed that man is a composite being, consisting of a body and the force that moves it and gives it life. He called this force the psyche, which is usually translated as the soul. The soul is superior to the body. It is rational in nature and is therefore a part of the realm of pure Ideas. It is eternal, although Plato is not specific about the form that its immortality takes after it leaves the body. At the end of the Laws, written when Plato himself was approaching death, he said that all man really knows about death is that it separates the soul from the body. The body is destroyed, but the soul passes on to a remote region.

The Dialogues of Plato

The Dialogues of Plato were various treatises of the ancient Greek philosopher Plato. They are presented in the form of dialogues, or conversations, often between Socrates and his associates. The dialogues make up nearly all of Plato's surviving works. They were written over a period extending from about 397 B.C. until his death in about 347 B.C.

Plato used the dialogues to set forth his ideas about such matters as beauty, goodness, knowledge, immortality, virtue, and the nature of reality. In the Republic, perhaps his most famous dialogue, he deals with justice and constructs an ideal human community. He also presents his celebrated theory of ideas, which states that there are eternal and perfect forms, called ideas, of which the world and all things in it are imperfect imitations.

The dialogues are usually grouped into three periods, which correspond to Plato's development as a philosopher. The earliest treatises, such as the Crito, Lysis, and Ion, show the influence of Socrates. In these dialogues, Plato argues that virtue is knowledge and can be taught. Some of the greatest dialogues, notably the Republic, Symposium, and Phaedo, were written during Plato's middle period. In them he develops his theory of ideas, analyzes the nature and ways of knowledge, and discusses love, virtue, and the immortality of the soul. The later dialogues include Laws, which describes another model human community; the Sophist, on metaphysics; and the Timaeus, a treatise on natural science that was highly regarded in the Middle Ages.

Plato's dialogue form was imitated by many other writers on philosophy, notably Cicero, St. Augustine, and the Irish bishop George Berkeley (1685-1753). The dialogues also exerted a profound influence on Christian thinking and on later Western philosophy.

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Comments 3 comments

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Paradise7 7 years ago from Upstate New York

Excellent and informative hub. I became your fan, on the strength of it.

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jackie_fish 5 years ago

I really enjoy Plato and his work more so his analogy of the cave

AIWANFO .O.PETER 4 years ago

I will afirmly say that his words are very educative it help to awaken the history as well as telling you of the past so as to fix presents occurrence.

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