Thought of Plato and Aristotle

Two Greek Philosophers between them Lay the Foundations of Moral Philosophy and the Science of Reasoning

For more than forty years one of the most familiar sights of Athens was the figure of Socrates, the Philosopher. Professing to know nothing himself, though styled by the Delphic oracle as the wisest of men, he haunted the market-place, the streets and the gymnasia, conversing with any he might meet, and, under the pretext of seeking knowledge for himself, trying to make men think. It was this constant button-holing and his thick-set ugly appearance, with its snub nose and piercing eyes, which made him known to every Athenian; but among the intellectuals he was revered for his philosophy.

Born in 470 B.C., from childhood he had been subject to trances, during which he claimed to have received the warnings of a “spiritual voice”. These warnings always contained prohibitions.

From his youth Socrates had been keenly interested in the religious, philosophical and scientific movements of his times. Physical science was then represented partly by the Ionian school of inquiry, which sought to discover how the universe came into being and what is the guiding spirit which moves it; and partly by certain of the Western schools, especially the Pythagoreans, who taught that the First Principle is to be found in Number that is to say, Number determines the harmonies in music, the movements of the sun, moon and stars and the proportions of architecture, and so on; so that eventually Number is easily identifiable with everything that is orderly, proper, right, good and beautiful. Socrates seems to have been especially interested in the theories of Diogenes of Apollonia who held that air, in various degrees of condensation, formed the sub-stratum of the material world.

The result of his thinking about all these various theories was that he framed a theory of his own, the Theory of Forms. According to this theory, the world of sense is related to that of thought by the participation of things in the “forms”, or patterns, which alone are permanent.

The theory may in the first place have been of Pythagorean origin, but Socrates developed it, both in its logical aspect and also as the key to morals. For example, just or courageous actions were viewed as becoming such by participation in the “forms” of justice and courage.

But Socrates owed more to the Pythagoreans. His mystical nature was attracted by the doctrine of the soul as a divine, immortal spark imprisoned in the body and released at death.

Socrates had risen rapidly to a position of note in intellectual Athenian society, and believing that he alone was conscious of his ignorance, he was convinced that he had a mission to convince others of the same truth about themselves. This mission he pursued until the close of his life, relentlessly and without ceasing, seeking opportunities of discussion, especially with the young, and exposing the inner contradiction of popular ideas, particularly in morals and politics. Aristophanes, in his famous comedy The Clouds, caricatured Socrates’s “thinking shop” and suggested that Socrates was the head of a community something like the Pythagoreans. But from the writings of one of his pupils who were destined to achieve a greatness that excelled his master’s, we are led to picture him as the centre of a circle of youths belonging to the best Athenian families, who are represented as regarding him with affectionate admiration.

Among the more orthodox Athenians, Socrates was bound to be unpopular for his ideas, especially those which revealed him as having a wider view of life than the conventional Athenian at this time, a view which looked beyond Athens and Greece, upon man as the brother of all men and a citizen of the world.

This was looked upon as a lack of patriotism, and it was not surprising, therefore, that sooner or later an attempt should be made to get rid of him.

“When he was at length arraigned in 399 B.C., it was on charges of impiety and corrupting the youth of Athens that he faced his 501 judges. To them he explained his life and actions, but when judgment was taken he was found guilty by a majority of 60.

His prosecutor demanded the death sentence. Socrates put forward the proposal that he should be fined half a talent (about £240). The judges were bound by law to accept one or other of the two proposals, and they chose death.

Socrates might easily have escaped, but he refused to do so, and a month after the trial he drank the hemlock poison, cheerful among Ms weeping friends, with whom he had spent his last hours discussing the immortality of the soul.

“Death”, he declared, “is either a state of nothingness or a change of the soul from this world to another. Wherefore, be of good cheer, and be assured that no harm can happen to a good man either in life or after death. The hour of departure has come; we go our ways, I to die, you to live. Which is better, God only knows.”

In the group which had attended Socrates in his last hours and had listened to the last expressions of wisdom from the courageous man who was fired by the rightness of his convictions, was his pupil Plato. Plato had been horrified by Socrates’s reception at his trial and by the final scenes in the death cell, in which he saw the intellectual blindness and cowardice of intellectually little men bent on destroying one of the great minds of the time.

In his account of the last hours which he has given in The Symposium, he has stated that the death of his master determined him to carry on the mission of his friend and mentor. It is implicit in the account that had he not embarked upon this undertaking he might not, in all probability would not, have developed his own philosophy which has had, and must continue to have, a permanent effect on world thought for all time.

At the death of Socrates Plato was twenty-eight. The event was such a shock to him that he felt that he must leave Athens, so he went to Megara, where he probably passed his time composing several of his now-famous Dialogues. A mathematician friend, Theodoras, then invited him to Cyrene, and from there he embarked on a tour of Egypt, Sicily and the Greek cities of Lower Italy.

In Sicily he fell foul of the tyrant Dionysius the Elder, because of the freedom of his speech, and it is thought that the story of his being sold into slavery on the orders of Dionysius has some basis in fact. Whether this happened or not, he returned to Athens about the year 386 B.C.

In Athens he began to teach partly in the gymnasium of the Academy and partly in his garden, situated on the Colonus. He taught without fees. From 386 B.C. until his death at the age of eighty-one in 347 B.C., except for two visits to Sicily, he taught without break in Athens.

Plato was born two years after the death of the great Athenian leader Pericles, and the world in which he grew up was one possessed by a desire to correct and restore the distracted social and political system of Greece. That system had culminated in the city-state of Athens, a democracy carried to its fullest conclusions, in which every citizen had a direct voice in the city’s affairs.

Plato set himself to understand Greek society in all its extent and depth, and it was this inquiry which brought him at the age of twenty into the circle of Socrates. In his later pursuit of this objective, it was his intention to point out, as his old master had done before him, the weaknesses of Greek society and to suggest remedies. In doing so, he struck out a system of philosophy of his own based on contemporary experience.

In the realm of logic and metaphysics, Plato took over certain results achieved by his predecessors, particularly by Socrates. Here his first task was to refute some of the logical heresies of some of the leading philosophers; for example, the destructive theory of Gorgias, Nothing is; if anything is, it cannot be known; if anything is, and can be known, it cannot be expressed in words. It was against this theory that Plato built up his Theory of Knowledge.

Put briefly, the Platonic Theory of Knowledge is based on three main assumptions. First, it is plausible to hold that the world of things is composed of individual objects; second, in the world of knowledge we are conscious of a collection of thoughts each different from all the rest; third, particulars in the external world, objects in space, appear to have an existence of their own, separate and independent of thoughts about them.

In his conclusions based on these assumptions, Plato puts forward the truer view; first, that the great number of objects in space, while each is separate and individual, possess each a character which is shared by other objects; second, that the simplest thoughts, although they occur as particulars, are also recognizable as more or less the same as other thoughts; and third, that things in space not merely correspond to thoughts in the mind, but that they are capable of being known.

Particular things and particular thoughts are what they are, because somehow they embody a universal nature or form. It was the main endeavour of Plato in this field to try to explain the relation of universals and particulars. His conclusions are summed up in his dictum: What is wholly real is wholly knowable; what is utterly non-existent is completely unknowable.

In the region of morals and politics, Plato was the first philosopher to offer a satisfying account of the principles that form and govern conduct and character. For him, morality is far from being intellectual in the sense of abstract. His’ justice” is the virtue of the good citizen.

In The Republic Plato visualized the founding of a city which would meet all human needs. What he was suggesting was a Utopia, and as such his city has come in for much criticism, particularly in modern times. But since it was to be this kind of city, the main requirement was for rulers able to carry on the work of the founder and the constitution and laws he prescribed. The ruler, the wielder of political power, must therefore be a philosopher.

It was in his description of his requirements for the Philosopher-Kings that Plato expounded his Idea of Goodness. “The Good”, he says, “is what every man sets out to attain with a vague awareness of its existence. … It is the Idea of the Good which imparts truth to things known, and the power of knowing to the mind. From it come knowledge and truth, both of them lovely, but it transcends them both and is lovelier still. To it they owe their being, but the Good is beyond being and far surpasses it in nobility and power.” In effect, this Idea of the Good corresponds to the Christian God, for Plato finds in it not merely the end of life, but the ground and cause of all existence.

The influence which Plato has had on all subsequent philosophies down to the present time can only be imperfectly estimated by considering the innumerable thinkers and poets of all ages who have drawn inspiration from him. He was succeeded by disciples who undertook to carry on his teaching, pre-eminent among whom was Aristotle, who must be regarded as his true successor and who developed Platonism on more scientific lines.

Aristotle was born in 3 84 B.C., two years after Plato began teaching in Athens. His father Nicomachus was physician to the grandfather of Alexander the Great, a fact which was to have a considerable influence on the great Greek conqueror and through him on the world.

At the age of seventeen he went to Athens, and there became a pupil of Plato, at whose feet he sat for seventeen years. At the end of this time he embarked on a life of adventure in Mysia, a district of Asia Minor, until in 343 B.C. he was summoned to Macedonia by Philip to undertake the education of his son, Alexander, then fourteen. For seven years, with a few interruptions, the profoundest intellect of the age was occupied with the training of the supreme man of action.

When in 334, Alexander “passed into Asia to subdue the world”, Aristotle returned to Athens, founded his Peripatetic School—so called because he walked about while he taught, and there lived, at the expense of his royal friend, for the next twelve years. When Alexander died in 323, remembering the fate which had overtaken Socrates, Aristotle retired to Euboeia, to spend the last months of his life in peace.

The basis of his philosophy is Plato’s ideas of particulars and universals, but Plato’s emphasis on the universals was modified by Aristotle through his strong scientific and biological leanings. In Aristotle the conviction that ideas have no existence apart from things, leads him to wage a war against the ideas of the Platonists relating to experience outside the senses. This engendered in him a passion for exact and comprehensive observation.

In every department of scientific inquiry he seeks to determine the facts, to register and classify the results, disposing of them in such a way that they reveal their true character, and form the materials out of which higher general ideas may emerge. This method he adopted in his approach to the whole field of knowledge.

Unfortunately, most of his works have been lost, but it is known that they included letters, speeches, poems, philosophical dialogues, treatises on national festivals, and manuals of natural history and rhetoric. Those works which have survived are not his highly finished literary efforts, but technical academic treatises, though they are, nevertheless, of the very greatest importance.

The greatest proportion of his writings that do exist are works on natural history and natural science. Many of them show traces of the limited nature of his early researches, but even so three of them. The History of Animals, On the Parts of Animals and On the Generation of Animals, draw from the leading modern scientist’s unqualified praise.

Of crucial importance is his Theory of Teleology, which he set out in a work Concerning the Soul In it he asserts that not only human life, but animal and plant life also, are dominated by a soul dwelling in every creature, which prevents the material body from decaying and determines its growth towards completion.

This principle, appearing at its highest in Man as mind, is the form, and efficient cause and end, of the physical organism. By this principle Aristotle was able to explain organic life and growth as a development from the “possibility of existing” to “actual existence”. It is a point of view which links Aristotle with general ideas about evolution.

He dealt with all the subjects to which he directed his attention in the same scientific way that he dealt with his investigations into natural science and history. He founded the science of reasoning, since called Logic. On six works collected under the title of Organon his fame rests as the inventor of Deductive Logic. It was as a rival to the Organon that Francis Bacon wrote his Novum Organum, which earned for him the title of inventor of Inductive Logic.

The influence which Aristotle had on all subsequent philosophers has equalled that exerted by Plato. His philosophy dominated the teaching of the universities of the Middle Ages, and still provides the starting point for many recent theories, for the powerful common sense which stamps all his reasoning, and the orderliness with which he worked, injected into the study of the ultimate problems a reality which “theory” lacks in its own primary nature. He was a philosophers’ philosopher, and as such he could not fail to have an influence on all future thought.