If Thales was the first of all the great Greek philosophers, Plato must remain the best known of all the Greeks. The original name of this Athenian aristocrat was Aristocles, but in his school days he received the nickname Platon (meaning "broad" ) because of his broad shoulders. (He is not the only great man to be known universally by a nickname. The Roman orator Cicero is another.)
Plato was born in Athens, about 427 B.C., and died there about 347 B.C. In early life Plato saw war service and had political ambitions. However, he was never really sympathetic to the Athenian democracy and he could not join wholeheartedly in its government. He was a devoted follower of Socrates, whose disciple he became in 409 B.C., and the execution of that philosopher by the democrats in 399 B.C. was a crushing blow. He left Athens, believing that until "kings were philosophers or philosophers were kings" things would never go well with the world. (He traced his descent from the early kings of Athens and perhaps he had himself in mind.)
For several years he visited the Greek cities of Africa and Italy, absorbing Pythagorean notions, and then in 387 B.C. he returned to Athens. (En route, he is supposed to have been captured by pirates and held for ransom.) There, the second half of his long life, he devoted himself to philosophy. In the western suburbs he founded a school that might be termed the first university. Because it was on the grounds that had once belonged to a legendary Greek called A cademus, it came to be called the Academy, and this term has been d for schools ever since.
Plato remained at the Academy for the rest of his life, except for two brief periods in the 360s. At that time he visited Syracuse, the chief city of Greek Sicily, to serve as tutor for the new king, Dionysius II. Here was his chance to make a king a philosopher. It turned out very badly. The king insisted on behaving like a king and of course made the Athenian democrats look good by comparison. Plato managed only with difficulty to return safely to Athens. His end was peaceful and happy, for he is supposed to have died in his sleep at the age of eighty after having attended the wedding feast of one of his students.
Plato's works, perhaps the most consistently popular and influential philosophic writings ever published, consist of a series of dialogues in which the discussions between Socrates and others are presented with infinite charm. Most of our knowledge of Socrates is from these dialogues, and which views are Socrates' and which are Plato's is anybody's guess. (Plato cautiously never introduced himself into any of the dialogues.)
Like Socrates, Plato was chiefly interested in moral philosophy and despised natural philosophy (that is, science) as an inferior and unworthy sort of knowledge. There is a famous story (probably apocryphal and told also of Euclid of a student asking Plato the application of the knowledge he was being taught. Plato at once ordered a slave to give the student a small coin that he might not think he had gained knowledge for nothing, then had him dismissed from school. To Plato, knowledge had no practical use, it existed for the abstract good of the soul.
Plato was fond of mathematics because of its idealized abstractions and its separation from the merely material. Nowadays, of course, the purest mathematics manages to be applied, sooner or later, to practical matters of science. In Plato's day this was not so, and the mathematician could well consider himself as dealing only with the loftiest form of pure thought and as having nothing to do with the gross and imperfect everyday world. And so above the doorway to the Academy was written, "Let no one ignorant of mathematics enter here."
Plato did, however, believe that mathematics in its ideal form could still be applied to the heavens. The heavenly bodies, he believed, exhibited perfect geometric form. This he expresses most clearly in a dialogue called Timaeus in which he presents his scheme of the universe. He describes the five (and only five) possible regular solids -- that is, those with equivalent faces and with all lines and angles, formed by those faces, equal. These are the four-sided tetrahedron, the six-sided hexahed ron (or cube), the eight-sided octahedron, the twelve-sided dodecahedron, and the twenty-sided icosahedron. Four of the five regular solids, according to Plato, represented the four elements, while the dodecahedron represented the universe as a whole. These solids were first discovered by the Pythagoreans, but the fame of this dialogue has led to their being called the Platonic solids ever since.
Plato decided also that since the heavens were perfect, the various heavenly bodies would have to move in exact circles (the perfect curve) along with the crystalline spheres (the perfect solid) that held them in place. The spheres were another Pythagorean notion, and the Pythagorean preoccupation with sound also shows itself in Philolaus belief that the spheres of the various planets made celestial music as they turned -- a belief that persisted even in the time of Kepler two thou sand years later. We still use the phrase "the music of the spheres" to epitomize heavenly sounds or the stark beauty of outer space.
This insistence that the heavens must reflect the perfection of abstract mathematics in its simplest form held absolute sway over astronomical thought until Kepler's time, even though compromises with reality had to be made constantly, beginning shortly after Plato's death with Eudoxus and Callippus.
In the dialogue Timaeus, by the way, Plato invented a moralistic tale about a thoroughly fictitious land he called Atlantis. If there is a Valhalla for philosophers, Plato must be sitting there in endless chagrin, thinking of how many foolish thousands, in all the centuries since his time, down to the very present day -- thousands who have never read his dialogue or absorbed a sentence of his serious teachings -- nevertheless believed with all their hearts in the reality of Atlantis. (To be sure, recent evidence of an Aegean island that exploded volcanically in 1400 B.C. may have given rise to legends that inspired Plato's fiction.)
Plato's influence extended long past his own life and, indeed, never died. The Academy remained a going institution until A.D. 529, when the Eastern Roman Emperor, Justinian, ordered it closed. It was the last stronghold of paganism in a Christian world.
Plato's philosophy, even after that date, maintained a strong influence on the thinking of the Christian Church throughout the early Middle Ages. It was not until the thirteenth century that the views of Aristotle gained dominance.
A fundamental but until then philosophically little-cultivated aspect of the Greek way of looking at nature came to the fore and asserted itself as the leading principle of the study of nature. What this new trend wanted to achieve above all was to secure an organic place for the personal, intuitive experience of man both in the understanding of himself and of the physical world. The most detailed formulation of this new approach to nature is Aristotle's physics and cosmology, but its most telling document is Plato's account in the Phaedo of Socrates' search for a science satisfying the needs and aspirations of man.1
It was a search for perspectives wide enough to support a stand that from the viewpoint of a consistent mechanistic philosophy had to appear the senseless acceptance of one's own death sentence. Clearly, the mechanistic philosophy of nature and man, as advocated by the Ionian philosophers, had no explanation and motivation for an attitude that preferred to abide by value judgments that were but noble illusions to an all-inclusive mechanistic interpretation of things, persons, and events.
Socrates was eager to point this out to his friends who begged him to avoid the inevitable course of a blatantly unjust sentence. The arguments of his friends, as Socrates noted, invariably fell back on the mechanistic explanation of generation and decay, and this appeared to him wholly inadequate even to cope with the most elementary organic processes. That explanations of that type were fascinating, he readily admitted. He could in fact refer to his experience as a youth on reading a book by Anaxagoras2 that offered explanations about such sundry items as generation and decay on the earth, motion of celestial bodies, and production of mental processes in the brain. Yet, on some reflection Socrates had to realize that these explanations left indeed much to be explained. Actually he found them confusing when applied to the elementary question of what is the cause of a man's growth.
It was no accident that Socrates' grappling with the gravest physical and spiritual issues of human life had ramifications that touched on the physical situation represented by the behavior of an organism. It was precisely in problems of this sort that atomism, Pythagoreanism, and the Ionian natural philosophy proved manifestly inadequate. Furthermore, it was because of the mishandling of such questions by some far-fetched generalizations of a "materialistic" physics that the understanding of man's own inner world came to be drastically debilitated.
The apparent brilliance of Ionian physics was not only fascinating but also blinding, as Socrates recalled his own experience, and could leave its admirers in a state of total confusion to what was really known. In ultimate analysis it made a shambles of the basic question of human inquiry: how to connect man's own intuitive, immediate judgments and reflections to the processes unfolding in the outside world. With regard to man's behavior, strivings, and findings there were the instinctively applied categ ories of purposeful and involuntary, good and bad, fitting and unfitting. Could these qualifications be absent in the phenomena of nature, to paraphrase Socrates' agonizing questions, if nature was to be understood or to be truly connected with man in an organic whole? After all the Ionians themselves, as Socrates recalled, seemed at times to hint that nature worked like a man planning to achieve carefully what was best. Anaxagoras, Socrates noted, even spoke of an all-pervading ause of all things.
But Anaxagoras' "mind" was not the source of the type of understanding Socrates looked for. While Socrates wanted to know why it was best for the earth to remain at rest in the center of the world, the Ionians, Anaximander to be specific, referred rather to the indifference of an object to move at all when equally distant from the extremes in all directions. Similarly deficient in Socrates' eyes were the other explanations offered by the Ionians for the stability of the earth. To hear that the earth had a flat bottom and was thereby securely supported by the underlying air conveyed only keen disappointment to him. He felt the same as he surveyed the views of the Ionians the nature and motion of the heavenly bodies. As to the sun and the planets, Anaximander identified them as small circular openings in a huge rim filled with fire, whereas Anaxagoras reduced the sun to a flaming stone. Both, however, were equally unconcerned why it was better for the planets and stars d.
The ultimate motivation of such a stratagem could not escape Socrates. He saw that the account of the physikoi of the stability and motion of the earth and heaven was but a covert replacement of old values with a new deity. For, as Socrates noted, the all-inclusive mechanism was offered as a new Atlas. Its worshippers, the physikoi, charged Socrates, "give no thought to the good which must embrace and hold together all things."3 In this they were at least consistent, as no goodness, or purpose could be predicated about the Atlas of the Ionian physicalism. Little wonder that Anaxagoras' all-pervading "mind" came to appear to Socrates as a mere travesty of the true mind, and the reasons it represented but a camouflage of the real causes.
Socrates with good reason called attention to the fact that voices, hearing, and breath were as little a complete explanation of human conversation as was the actual position of his bones and muscles the ultimate reason of his refusal to escape from prison. The upshot of such considerations was, as can be readily guessed, a search for causes in a sense diametrically opposite to the approach taken by the Ionians or by the atomists. To continue in their footsteps, warned Socrates, was to expose one's mental eyes to total and irreparable blindness. Such at least was the uppermost consideration that made him chart the course of his own intellectual orientation on which, unfortunately, hardly a stopover was left for the study of mechanical causes. Extreme and deplorable as this choice was, in the context of the times it appeared inevitable. More important, many generations after him conformed faithfully to the mental attitude expressed so graphically in the Phaedo:
After this, then, since I had given up investigating realities, I decided that I must be careful not to suffer the misfortune which happens to people who look at the sun and watch it during an eclipse. For some of them ruin their eyes unless they look at its image in water or something of the sort. I thought of that danger, and I was afraid my soul would be blinded if I looked at things with my eyes and tried to grasp them with any of my senses. So I thought I must have recourse to conceptions and examine in them the truth of realities.4
This lofty program was carried on by a genius no less persuasive than Plato. In his works one comes across time and again the basic charge against the Ionians that their approach to nature separated man from nature, and nature from the realm of the good and beautiful. There one finds formulated explicitly the paramount issue, as felt by Socrates' disciples, namely, the role to be assigned to the phenomenon of life in explaining nature. What Plato found particularly repulsive in the Ionian's system was that the whole gamut of the manifestation of the living, vegetative, animal, and psychical was taken by them as the chance product of "absolutely inanimate existences,"5 such as fire and water, earth and air. To this Plato resolutely opposes the primacy of life, which embraces matter and mind alike, and defends the method of explaining the whole and parts of the universe in terms of an organism.
Plato's principal work touching on scientific questions, the Timaeus, bluntly states that this world "in very truth [is] a living creature with soul and reason."6 To this viewpoint Plato accords an unconditional primacy even in matters of detail. Thus when he discusses the working of the human eye, he deplores the fact that "the great mass of mankind regard [the geometrical and mechanical aspects of the question] as the sole causes of all things." Against this he opposes the classification of causes into two groups: the accessory or mechanical causes that are "incapable of any plan or intelligence for any purpose," and those that "work with intelligence to produce what is good and desirable."7 The reaffirmation of the Socratic or organismic approach in science could hardly be more unequivocal.
Such an emphasis on the concept of organism as the basic framework in which the cosmos is to be explained derived only in part from factors like the emergence in the fifth century of the Hippocratic medical theory and practice. The principal factor was a deeper and more universal one. It was rooted in the Greek nature as such and was given unchallenged prominence when cultural developments forced the Greek mind to reflect on the consequences of a mechanistic explanation of the inanimate and animate world including man both as an individual and as a member of society. The "Greekness" of the organismic approach can be seen in the fact that they first applied the term cosmos to a patently living thing - a well-ordered society - and only afterward to the orderliness of the physical world.8 Rooted deeply in their personal, cultural inclinations, this organismic approach to reality, once it became the conscious possession of the Greeks, had never been seriously questioned or abandoned by them. Sing le views of the Ionians and atomists continued, of course, to play seminal roles in Greek science. What is more, once the cultural crisis evidenced by the activity of the Sophists was over, even the poets began to take more kindly to the physikoi, who for awhile were the principal targets of plays concerned with the source of various cultural evils. At any rate, the Ionians ceased to be called in literary circles, as Plato remarks, "she dogs uttering vain howlings and talking other nonsense of the same sort."9 This was, however, merely a concession that could easily be meted out by those who won the cultural battle. For as Plato could confidently state in the same context, the authority of the mechanical views had been checked, or to paraphrase his words, the case was reversed in favor of the organismic viewpoint.
1 Plato, Phaedo, see especially sections 96 101, pp. 78-82.
2 Anaxagoras. See Gershenson, 1964, pp. 1-51.
3 Plato, Phaedo, 99C.
4 Plato, Phaedo, 99D-E.
5 Plato, Laws, 889.
6 Plato, Timaeus, 30B.
7 Plato, Timaeus, 46B-E.
8 See Cornford, 1912, p. 53.
9 Plato, Laws, 967
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