GREEK PHILOSOPHY

Plato (427-347 B.C.) [Athens]
1. Life of Plato
  One of the greatest of the Greek philosophers. He was born either in Athens or on the island of Aegina, and was originally known as Aristocles. His father was Ariston who traced his ancestry to the last of the kings of Athens. His mother, Perictione, was a descendant of the family of Solon. Plato was given the best education possible and originally intended to pursue a political career, which was natural for a young man of his background. He became disgusted with politics and abandoned the idea of a political career. He became acquainted in his youth with the Heraclitean Sophist, Cratylus. From him Plato learned that the world of sense-perception is a world of change, from which no true and certain knowledge can be obtained. That true and certain knowledge is obtainable only on the conceptual level by reason was later learned from Socrates with whom he spent eight years, from his own twentieth year to the death Socrates, as an ardent follower. Plato was present at the trial of Socrates, but was absent from the death-scene because of illness. After the death of Socrates Plato traveled in Greece, Italy, Sicily and Egypt. He spent some time with the Megarian Socratics, and also visited the Pythagoreans in Sicily who survived the dispersion of their communities. He met and became acqainted with Archytas, the learned Pythagorean. The change of tone and doctrine from the earlier Socratic to the later mystic group of dialogues is due to this contact with Pythagoreanism, a type of philosophy which seems to have been little known in the Athens of Plato's youth. He also acquired a knowledge of Heraclitean, Eleatic and other Pre-Socratic philosophies. While in Sicily Plato was invited to the court of Dionysius I, Tyrant of Syracuse, where he became a friend of Dion, the Tyrant's brother-in-law. Plato eventually returned to Athens and at the age of forty in 387 B.C. set up his own school of mathematic and philosophy near the sanctuary of the hero Academus, from which it became known as the Academy. Here he taught with great success until his death at the age of eighty. His career as a teacher was interrupted on two occasions by a second and third trip to Sicily, where Plato attempted without much success to educate and advise Dionysius II. In 367, the year he died, Dionysius I left his brother-in-law, Dion, as regent for his young son and heir, Dionysius II. Dion conceived the idea of putting into practice the educational and political theories of Plato and he invited Plato to come to Syracuse in order to take in hand the education of Dionysius II, then about thirty years old. If, as Plato argued, a really good state was unattainable until philosophers were kings or kings philosophers, then here, Dion argued, was an ideal opportunity to try make a philosopher out of a king. Plato decided to go, apparently not altogether willingly, and set the Tyrant to a course of geometry. But theory shattered on the harsh rock of real politics in Syracuse. Four months after Plato's arrival Dion's position was undermined by rival groups around the throne and Dionysius' jealousy of Dion got the upper hand, and Dion was exiled from Syracuse. After some difficulty the philosopher managed to return to Athen, whence he continued to instruct Dionysius by letter. Attempts to reconcile the Tyrant and his uncle did not succeed and Dion took up residence in Athens, where he worked with Plato. In 361, Plato made a third journey to Syracuse at the earnest request of Dionysius who wished to continue his philosophical studies. But this visit failed to achieve anything. Plato was unable to secure the recall of Dion, whose fortune was confiscated by his nephew. In 360 Plato returned to Athens, feeling that his dream of a philosopher-king had failed. In 357 B.C. Dion succeeded in making himself master of Syracuse, but he was murdered in 353 B.C., to the great grief of Plato.
2. Works of Plato
  The works of Plato are very well preserved; we have more than twenty-four authentic dialogues which were written for popular reading, certain letters, as well as some definitions which are probably spurious. This is very considerable body of literature on which to found an understanding of Plato's philosophy. The following list of his works in chronological order is taken from Frederick Copelstone A History of Philosophy, vol. I, part I, pp. 163-165.
  1. Socratic Period.
    In this period Plato is still influenced by the Socratic intellectual determinism. Most of the dialogues end without any definite result having been attained. This is characteristic of Socrates' "not knowing."
    1. Apology. Socrates' defence at his trial.
    2. Crito. Socrates is shown as the good citizen who, in spite of his unjust condemnation, is willing to give up his life in obedience to the laws of the state. Escape is suggested by Crito and others, and money is provided; but Socartes declares he will abide by his principles.
    3. Euthyphron. Socrates awaits his trial for impiety. Inquires into the nature of piety. No result from the inquiry.
    4. Laches. On courage. No result.
    5. Ion. Against the poets and rhapsodists.
    6. Protagoras. Virtue is knowledge and can be taught.
    7. Charmides. On temperance. No result.
    8. Lysis. On friendship. No result.
    9. Republic. Book I. On justice. (The Apology and Crito must obviously have been written at an early date after Socrates' death. Probably the other dialogues of this group were written within ten years after Socrates' death.)
  2. Transition Period.
    In this period Plato is finding his way to his own philosophy. The doctrines characteristic of Orphism and Pythagoreanism for the first time make their appearance. Gorgias was probably composed shortly before or after 387 B.C., the year Plato returned from his travels aboard, at the age of forty, to set up his school.
    1. Gorgias. The practical politican, or the rights of the stronger versus the philosopher, or justice at all costs.
    2. Meno. Teachability of virtue corrected in view of the theory of ideas.
    3. Euthydemus. Against logical fallacies of later Sophists.
    4. Hippias I. On the beautiful.
    5. Hippias II. Is it better to do wrong voluntarily or involuntarily?
    6. Cratylus. On the theory of language.
    7. Menexenus. A parody on rhetoric. (The dialogues of this group were probably composed before the first Sicilian journey.)
  3. Period of Maturity.
    Plato is now in possession of his own philosophy. Platonism, which means principally the theory of forms or Ideas, and belongs to the Orphic and Pythagorean mystic tradition. Platonism is an offshoot of Pythagoreanism, and is another attempt to succeed, where Parmenides had failed, in relating the One and the Good, who is God, to a manifold and changing world. In these dialogues the Theory of the Ideas makes its appearance at the same moment with the doctrine of the soul's immortality and divinity; the whole argument of the Phadeo is that the two doctrines stand or fall together. Thus the mystic doctrine of the immortality and divinity of the soul is linked together with the Theory of the Ideas. This makes a strong prima facie case for interpreting the Theory of Ideas from the mystic standpoint and that they were inspired by the same view of the world and of life and death that gave rise to the systems of Parmenides and Empedocles.
    1. Symposium. All earthly beauty is but a shadow of true Beauty, to which the soul aspires by Eros.
    2. Phaedo. Ideas and Immortality of the Soul.
    3. Republic. The State. Ontological dualism strongly emphasized.
    4. Phaedrus. Nature of love; the possibility of philosophic rhetoric. The tripartition of the soul, as in the Republic. (These dialogues were probably composed between the first and second Sicilian journeys.)
  4. Works of Old Age.
    1. Theaetetus. Knowledge is not sense-perception or true judgment. (The later part of this dialogue was composed after the Parmenides.)
    2. Parmenides. Defence of the Theory of Ideas against criticism.
    3. Sophistes. The Theory of Ideas considered.
    4. Politicus. The true ruler is the knower. The legal State is makeshift.
    5. Philebus. Relation of pleasure to the Good.
    6. Timaeus. Natural science. Demiurge appears.
    7. Critias. Ideal agrarian State contrasted with imperialistic sea-power, "Atlantis."
    8. Laws and Epinomis. Plato makes concessions to real life, modifying the Utopianism of the Republic. (Of these dialogues, some may have been written between the second and third Sicilian journeys, but the Timaeus, Critias, Laws and Epinomis were probably written after the third journey.)
    9. Letters 7 and 8 must have been written after the death of Dion in 353 B.C.
3. Philosophy of Plato
  1. Theory of Knowledge.
    Plato's theory of knowledge cannot be found systematically and completely stated in any one dialogue. The dialogue Theaetetus is devoted primarly to the problems of knowledge, but its conclusion is negative, since therein Plato is concerned to refute false theories of knowledge, especially the theory that knowledge is sense-perception. Plato had already stated by the time he wrote Theaetetus his theory of degrees of knowledge and the corresponding heirarchy of being in the Republic. The negative and critical side of his epistemology will be first summarized and then the positive and constructive side will be presented. The very character of Plato's epistemology makes it almost impossible to separate his epistemology from his ontology.
    1. Knowledge is not sense-perception.
      Socrates refused to accept the Sophist position that truth is relative, that there is no stable norm, no abiding object of knowledge. In particlular he rejected the theory of Protagoras that knowledge is perception, that what appears to an individual to be true is true for that individual. Plato accepts Socrates' position but he wants to demonstrate this fact theoretically. His method is to obtain dialectically a clear statement of the theory of knowledge implied by the Heraclitean ontology and the epistemology of Protagoras, and its consequences, and to show that that conception of knowledge does not fulfil the criterion of true knowledge. True knowledge, according to Plato, is (i) infallible, and (ii) it is of what is. Sense-perception is neither. Knowledge, if it is knowledge at all, must be knowledge of something; knowledge is necessarily related to some particular type of object. True knowledge is of something that is, being. The objects of perception never are, they are always becoming. (Plato does not, of course, accept Heraclitus' doctrine that all is becoming, but does accept that the objects of sense-perception are becoming, drawing the conclusion that knowledge and sense-perceptions are not the same.) My sense perception is true for me at the moment I experience the perception. And if knowledge is perception, than the thing I perceived in the past cannot be knowledge, because I am not now perceiving it but remembering it. Remembrance is not sense-perception. Therefore, knowledge cannot be equated to perception. In his dialogue Theaetetus Plato shows that
      (1) Perception is not the whole of knowledge, for a great part of what is generally recognized as knowledge consists of truths whose objects are not objects of sense perception at all. And there is knowledge about sensible objects, which is not known immediately by perception, but by intellectual reflection. Plato gives existence or non-existence as examples. Suppose that a man sees a mirage. His immediate perception does not inform him as to the objective existence or non-existence of the mirage perceived; it is only rational reflection that can tell him this. Also the general truths of mathematics and other sciences are not apprehended by the senses. Universal truths are not immediately perceived by the senses.
      (2) Sense-perception, even within its own sphere, is not knowledge, that is, the truth about anything. Sense perceptions just are; the truth about the objects of sense-perception is given in reflection, in rational judgment, not in the bare sensation. For example, the railway tracks appear to converge in the distance: it is in intellectual reflection that we know that are really parallel. In general, reason must arbitrate and interpret the confusing and conflicting senses. Sense perception is not true knowledge.
    2. Knowledge is not simply "True Judgment." Judgments cannot simply be knowledge because a judgment may be false. Then are true judgments knowledge? No, because a judgment may be true without the fact of its truth involving knowledge on the part of man making the judgment. A true judgment might be made by a man without him knowing that it is true. If I were at this moment to make the judgment "President Gorbachev is talking to President Bush over the telephone," it might be true; but it would not involve knowledge on my part. It would be a guess, as far as I am concerned, even though the judgment were objectively true. It might be a true judgment but it is not knowledge. So knowledge is not simply true judgment.
    3. Knowledge is not True Judgment plus "Account." A true judgment is a true belief but a true belief is not knowledge. Can a true belief be converted into knowledge by adding an "account" or explanation (logos) to it? What does giving an account mean?
      (1) If giving an account of a true judgment means expressing the true belief in words, then there would be no difference between true belief and knowledge. But we have already seen that there is a difference between making a judgment that happens to be true and making a judgment that one knows to be true.
      (2) If giving an account or explanation of true judgement means analyzing it into elementary parts, then will giving its elementary parts convert a true belief into knowledge? No, not any more than being able to list the parts of an automobile means that I know how an automobile operates.
      (3) If giving an account means being able to name some mark by which the thing differs from everything else, then will not this characteristic or mark convert a true belief into knowledge? No, for the following reason: If knowledge of a thing means the addition of its distinguishing characteristic to a true notion of that thing, we are involved in the absurd position of adding to the true notion of thing its distinguishing characteristic which is already contained in the true notion of the thing. That is, unless this distinguishing characteristic were already contained within my true notion of the thing, how could the latter be called a true notion? And if it already contains the thing's distinguishing characteristic, adding it is redundant and will not convert a true belief into knowledge. The point is not that no knowledge is attained by definition, but rather that the individual, sensible object is indefinable and is not really a proper object of knowledge at all. This is the real point of this dialogue, Theaetetus, namely, that true knowledge of particular sensible objects is unattainable.
    4. True knowledge. Plato has assumed from the beginning that knowledge is attainable, and that it must be (i) infallible and (ii) of that which is. True knowledge must possess both of these characteristics and any state of mind that cannot be show to have both of these characteristics cannot be true knowledge. Plato accepted from Protagoras the belief in the relativity of senses and sense-perception, but he did not accept a universal relativism: on the contrary, he held that knowledge is attainable and it is absolute and infallible. But it cannot be the same as sense-perception. Plato also accepted from Heraclitus the view that the objects of sense-perception are always in a state of becoming, of flux, and so are unfit to be objects of true knowledge. They are coming into being and passing away, they are indefinite in number, cannot be clearly grasped in definition and cannot become the objects of true knowledge. But from this Plato does not draw the conclusion that there are no objects of true knowledge, but only that sensible particulars cannot be the objects of true knowledge. The object of true knowledge must be stable and abiding, fixed, unchanging, capable of being grasped in clear and universal definitions, as Socrates saw. True knowledge is knowledge of the universals; they alone are stable and unchanging. For example, in the judgment "The Athenian Constitution is good" the essentially stable element in this judgment is the concept of goodness. After all, the Athenian Constitution might be so changed that it could no longer called good, but bad. This implies that the concept of goodness remains the same, for it is with reference to a fixed concept of goodness that a changed Constitution may be judged bad. And these fixed and stable concepts (predominantly ethical values) are captured in the definition of the concept. And definitions concerns the universal. The universal fulfils the requirements for being an object of true knowledge; it is true always and everywhere. And knowledge of the highest universal is the highest kind of knowledge, while "knowledge" of the particular is the lowest kind of "knowledge." Thus Plato makes a distinction between knowledge of universals and "knowledge" of particulars. He referred to the "knowledge" of particulars as "opinion" (doxa) and the knowledge of universals alone as knowledge (episteme).
      (1) The Divided Line.
      Plato's positive doctrine of knowledge, in which degrees or levels of knowledge are distinguished according to their objects, is set forth in the famous passage of the Republic that gives the simile of the divided line. I give here the usual schematic diagram, which I will endeavor to explain.
```
           opinion           |               knowledge
                             |
imagination    |    belief   |  understanding     |    reason
---------------|-------------|--------------------|-----------------
reflections of |   images    |  intelligible      | first principles
   images      |             |  particulars       |
                             |
           sensible          |              intelligible
```
      Plato's theory of knowledge can hardly be discussed apart from his theory of reality. The terms or names above of the line belong to his theory of knowledge and the terms or names below the line belong to his theory of reality and refer to the corresponding objects of knowledge in the "real" world. The line is divided in half: the half to the left repesents sense perception through which man comes to know the changeable world of particular bodies; the half to the right represents the intellect or mind through which man comes to know the unchangeable world of Ideas or Forms, of the immutable essences, of the universals and intelligible realities. The half to the left is labeled "opinion" and the half to right is labeled "knowledge." According to Plato the development of the human mind on its way from ignorance to knowledge takes place over these two main fields: from opinion on the left to knowledge on the right. The line is not simply divided into two sections, but each main section is subdivided. Thus there are two degrees of opinion and two degrees of knowledge. How are we to interpret these subsections? The two degrees of opinion are imagination (eikasia) and belief (pistis). For example, a man whose only idea of justice is that embodied in the imperfect justice of the Athenian Constitution or of some particular man, is in the state of opinion in general. But if a rhetorician comes along, and with specious words and reasonings persuades him that things are just and right, which in reality are not even in accord with the imperfect justice of the Athenian Constitution and its laws, then his state of mind is that of imagination (eikasia). What he takes for justice is but a shadow, reflection, or caricature of what is only an image, when compared to the universal Form. The state of mind, on the other hand, of the man who takes as justice the justice of the Constitution and laws of Athens or the justice of a particular just man is that of belief (pistis). He has a copy of the real Idea of justice, but the man in the imagination state of mind has a copy of the copy, and maybe a very distorted copy of the copy. That is, a man whose only idea of a horse is that of particular real horses, and who does not see that particular horses are imperfect "imitations" of the ideal horse (the universal horse), is in a state of belief. He has not got knowledge of the horse, but only opinion. Now if an artist now comes along and paints a picture of a horse, the painted horse is an imitation of an imitation. Anyone who took the painted horse to be the real horse would be in a state of imagination (eikasia), while anyone whose idea of a horse is limited to the particular horses he has seen, heard or read about, and who has no grasp of the universal Idea, is in a state of belief (pistis). But the man who apprehends the ideal horse, the specific form of which particular horses are imperfect realizations, is in a state of knowledge (episteme). The knowledge or right section of the line is also divided into two subsections. How are we to interpret these two subsections? In general they are to be connected, not with visible (orata) or sensible objects (the left side of the line), but with the invisible (aorata) or intelligible world. But what of the subdivision? How does understanding (dianoia) differ from reason (noesis)? They are to refer to a distinction of state of mind and not only to a distinction of objects. The reason (noesis) is the higher and refers to first principles (archai). Their objects are the Forms or Ideas of the Good and the Beautiful. The understanding (dianoia) is the state of mind of those who use hypotheses such as the mathematican and scientists. Plato does not use the word "hypothesis" in the sense of a judgment which is taken as true while it might be untrue, but in the sense of a judgment which is treated as if it were self-conditioned, not being seen in its ground and in its necessary connection with being or first principles. Reason (noesis), on the other hand, is that state of mind of the man, the philosopher, who uses the hypotheses of the understanding (dianoia) as starting points, but passes beyond them and ascends to first principles (archai). The objects of the understanding (dianoia) are mathematical objects (ta mathematika). They are not just numbers and geometrical objects, such as circles, points and lines, but they are all intelligible objects who are "above" sensible particulars but "below" true universals. They are intelligible particulars.
      (2) The Allegory of the Cave.
      Plato further illustrated his epistemological doctrines by his famous allegory of the Cave in the seventh book of the Republic. It shows clearly the ascent of the mind from ignorance to knowledge, and that Plato regarded this process, not so much as a continuous development but as a series of "conversions" from less adequate to more adequate congnitive states. Imagine an underground cave which has opening toward the light. In this cave are living human beings, with their legs and necks chained from childhood in such a way that they cannot turn around but face the inside, back wall of the cave, so that they have never seen the light of the sun. Now above and behind them, that is, between the backs of the prisoners and the mouth of the cave, is a fire, and between them and the fire is a raised way and a low wall, like a screen. Along this raised way there pass men carrying statues and figures of animals and other objects, in such a manner that the objects appear over the low wall or screen. The prisoners, facing the back inside wall of the cave, cannot see one another nor the objects carried behind them, but they see the shadows of themselves and of these objects thrown on the back wall of cave they are facing. They see only shadows. These prisoners represent the majority of mankind, that multitude of people who remain all their lives in a state of imagination (eikasia), beholding only shadows of reality and hearing only echoes of the truth. Their view of the world is most inadequate, distorted by "their own passions and prejudices, and by the passions and prejudices of other people as conveyed to them by language and rhetoric." And though they are no better than children, they cling to their distorted views with all the tenacity of adults, and have no wish to escape from their prison-house. Moreover, if they were to escape and look at the objects of which they had only seen the shadows, they would be blinded by the glare of the light, and would imagine that the shadows were far more real than the objects. Now if one of the prisoners who has escaped grows accustomed to the light of the fire, he will after a time be able to look at the objects, of which he had previously seen only the shadows. This man beholds his fellows in the light of fire and is in a state belief (pistis), having been "converted" from the shadow world of reflected images (eikones) to the world of the images, though he has not yet ascended to the world of intelligible, invisible realities. He sees the prisoners for what they are, namely prisoners, prisoners in the bonds of passion and sophistry. Now if he perseveres and comes out of the cave into the sunlight, he will see the world of sun-illuminated and clear objects (which are the intelligible realities), and lastly, though only by an effort, he will be able to see the sun itself, which represents the Idea of the Good, the highest Form, "the universal cause of all things right and beautiful - the source of truth and reason." He will then be in the state of mind called reason (noesis). Plato remarks that if that escaped prisoner were to return to the cave, he would be unable to see properly in the darkness and would appear "ridiciulous;" if he tried to free another and lead him to the light, the prisoners, who love the darkness and consider the shadows to be true reality, would put the offender to death, if they could but catch him. Here Plato is probably referring to Socrates, who endeavored to enlighten all those who would listen and make them apprehend truth and reason, instead of letting themselves be misled by prejudice and sophistry.
  2. The Theory of Ideas.
    Plato's epistemology clearly implies that the universal which are conceived in thought are not without objective reference. In what does this objective reference consist? The answer to this question will describe Plato's ontology and theory of reality.
    1. In the Republic Plato assumed that whenever a plurality of individuals have a common name it had a corresponding idea (idea) or form (eidos). This is a universal, the common nature or essence which is grasped in the concept. Take beauty for example. There are many beautiful things, but we also have a universal concept of beauty itself. Plato assumed that these universal concepts are not merely subjective concepts, but that they have an objective reality. At first hearing this sounds like a strange and maybe naive view, but we must remember that for Plato it is thought that grasps reality, so that just as the objects of perception are real so the objects of thought, the universals, must be real. How could they be grasped by the mind and made the objects of thought unless they were real? We do not make them with our mind; we discover them. Another point to remember is that Plato was at first concerned with universal moral and aesthetic norms and standards, and given the main interest of Socrates, it was natural for him to think of Absolute Goodness or Absolute Beauty existing in their own right. Later when Plato came to turn his attention more to natural objects than he had done before and to consider class-concepts, such as those of man or horse, it was obviously rather difficult to suppose that universals corresponding to these class-concepts existed in their own right as objective essences. One may easily identify Absolute Goodness with Absolute Beauty, but it is not so easy to identify the objective essence of man with the objective essence of horse. The attempt to do so would seem to be ludicrous. But some principle of unity had to be found, if the essences were not to be left in isolation one from another. Plato came to devote much attention to finding this principle of unity, so that all the specific essences might unified under or subordinated to one supreme generic essence. Plato tackles this problem from the logical point of view, inquiring into the problem of logical classification; he doubtless thought that by settling the problem of logical classification he was also settling the problem of ontological unification.
    2. To these objective essences Plato gave the name of Ideas or Forms (ideai or eide), words which are used inchangeably. The Greek word translated "idea," eidos, in this connection appears suddenly in the Phaedo. But we must not be misled by this use of the term "Idea." "Idea" in ordinary parlance means a subjective concept in the mind, as when we say: "That is only an idea and nothing real." But Plato, when he speaks of Ideas or Forms, is referring to the objective content or reference of our universal concepts. In our universal concepts we apprehend objective essences, and it is to these objective essences that Plato applied the term "Ideas." In some dialogues, for example, in the Symposium, the word "Idea" is not used, but the meaning is there, for in that dialogue Plato speaks of essential or absolute Beauty (auto ho esti kalon, "it itself which is beautiful"), and this is what Plato would mean by the Idea of Beauty. Thus it would be a matter of indifference, whether he spoke of the Absolute Good or of the Idea of the Good: both would refer to an objective essence, which is the source of goodness in all particular things that are truly good.
    3. Since by Ideas or Forms Plato meant objective essences, it is of paramount importance for an understanding of the Platonic ontology to determine precisely how he regarded these objective essences.
      (1) Do the Ideas or Forms have a transcendental existence of their own, apart from particular things? Yes, but Plato's language often implies the existence of a separate world of transcendental essences. But this must not be taken to mean that the Ideas are spatially separate from things. Transcendance in this connection only means that the Ideas do not change and perish with the sensible particulars. The Ideas are non-corporeal and spiritual; the categories of time and space, of spatial separation, simply do not apply in the case of that which is essentially spiritual. In the case of that which transcends space and time, the question "Where is it?" is meaningless.
      (2) If so, what is their relation to one another and to the concrete individual objects of this world? The universals of the Good and Beauty interpenetrate and are ultimately identical. Within the world of Forms, there is a certain hierarchy. At the top is the Idea of the Good. It gives being to all the lower Forms. In the Sophist Plato clearly indicates that whole complex of Forms, the hierarchy of genera and species, is contained in an all-pervading Form, that of Being, and that by division of the genera and species the structure of the Forms is seen. The process of division continued until lowest species is reached that cannot be further divided. These he called the atomic Forms (atoma eide). The atomic Forms constitute the lowest rung of the ladder or hierarchy of Forms. Plato probably thought by bringing down the Forms, by a process of division, to the border of the sensible sphere, he was providing the connecting link between invisible world of Forms and the visible world of individual things. Plato speaks of the relation of the sensible individuals to their Idea in two not mutually exclusive ways:
      (a) As a "participation" (methexis) of the imperfect individuals in their perfect Idea and
      (b) as an "imitation" (mimesis) of the Idea by the individual, the particular objects being a likeness (homoiomata) and an imitation (mimemata) of the Idea, the latter being the exemplar or paradigm (paradeigma). In the Parmenides objections are raised against this way of explaining the relation of the many individual things to the Ideas.
      (3) Does Plato duplicate the world of sense-experience in the transcendental world of invisible, immaterial essences? No, because the Forms of this intelligible world are universals and not concrete individuals. Thus it does not duplicate the world of sensible individuals objects.
      (4) What is the relation of this world of essences to God? It seems that Plato did not hold that the Ideas were in the mind of God, like the later Neo-Platonists. In the Timaeus the Demiurge does not create the Ideas nor is he their Source, but he uses them to "create" the world of sensible things. If the Demiurge is God then the Ideas are above and separate from God.
    4. Theory of Forms and Pre-Socratic Philosophy.
      The Theory of Forms was an enormous advance on pre-Socratic philosophy.
      (1) Plato broke away from the de facto materialism of the pre-Socratics, asserting the existence of immaterial and invisible Being, which is not a shadow of this world but is more real than the material world.
      (2) While agreeing with Heraclitus, that sensible things are in a state of flux, of becoming, so that they can never really be said to be, Plato saw that this is but one side of the picture: there is also true Being, a stable and abiding Reality, which can be known, which is indeed the supreme object of knowledge.
      (3) On the other hand, Plato did not fall into the position of Parmenides, who by equating the universe with a static One, was forced to deny all change and becoming. For Plato the One is transcendent, so that becoming is not denied but is fully admitted in the "created" world.
      (4) Moreover, Reality itself is not without Mind and life and soul, so that there is spiritual movement in the Real.
      (5) The transcendent One is not without the Many, just as the objects of this world are not entirely without unity, for they participate in or imitate the Forms and so partake in order to some extent. The Many are not fully real, but they are not mere Not-being; they have a share in being, though true Being is not material. Mind and its effect, order, are present in the world: Mind or Reason permeates as it were, this world and is not a mere Deus ex machina, like the Nous of Anaxagoras.
    5. Theory of Forms and Socratic Philosophy.
      Plato's Theory of Forms is also an advance on the Sophists and on Socrates.
      (1) On the Sophists, because Plato, while admitting the relativism of bare perception, refused, as Socrates had before him, to accept the relativity of knowledge and moral values.
      (2) On Socrates himself, because Plato extended his investigations beyond the sphere of ethical standards and definitions into the spheres of logic and ontology. Moreover, while Socrates did not attempt any systematic unification of Reality, Plato did.
      (3) Socrates and the Sophists represent a reaction against the pre-Socratic systems of cosmology and against the speculations concerning the One and the Many. Plato in contrast to them took up again the problems of pre-Socratics and moved them up to a much higher plane, without losing the position won by Socrates. Plato thus attempted the synthesis of what was valuable in the pre-Socratic and Socratic philosophies.
    6. Plato's Theory of Forms is unsatisfactory. Even if all the Forms are united in the One and Good, which represents for him the ultimate Principle and contains all the other Forms, there remains the Separation (chorismos) between the intelligible and the purely sensible world. Plato may have thought that he had solved the problem of the Separation from the epistemological standpoint, by his doctrine of analysis or division (diairesis) comprehending the sense particular within the atomic Forms (atoma eide); but, ontologically speaking, the sphere of pure Becoming remains unexplained. (It is doubtful if the Greeks ever "explained" it.) Thus Plato does not appear to have cleared up satisfactorily the meaning of "participation" (methexis) and "imitation" (mimesis). In the Timaeus he says explicitly the Forms never enter "into anything else anywhere," a statement which shows clearly that Plato did not regard the Form or Idea as an intrinsic constituent of the physical objects. The physical objects are for Plato no more than imitations or mirror-images of the Ideas. The sensible world exists "alongside" the intelligible world, as the latter's shadow and fleeting image. Plato's idealism is a dualism because he does not say that the sensible world is a mere illusion and not-being, as Parmenides did. But the Separation (chorismos) remains an unresolved problem in Plato's philosophy, which his pupil Aristotle will try to solve.
  3. Plato's Physics.
    1. In the Timaeus Plato gives an explanation of the generation of the world. The sensible world is becoming, and "that which becomes must necessarily become through the agency of some cause." The agent referred to is the divine Craftsman or Demiurge. He "took over" all that was discordant and unordered motion, and brought it into order, forming the material world according to an eternal and ideal pattern, and fashioning it into "a living creature with soul and reason" after the model of the ideal Living Creature, that is, the Form that contains within itself the Forms of "the heavenly race of gods, the winged things which fly through the air, all that dwells in the water, and all that goes on foot on the dry earth." As there is but one ideal Living Creature, the Demiurge made but one world.
    2. Why did the Demiurge so act? The Demiurge is good and "desires that all things would come as near as possible to being like itself," judging that order is better than disorder, and fashioning everything for the best. He was limited by the material at his disposal, but he did the best that he could with it, making it "as excellent and perfect as possible."
    3. What is the Demiurge? He must at least represent the divine Reason which is operative in the world; but he is no Creator-God. It is clear from the Timaeus that the Demiurge took over a pre-existing material and did his best with it; he did not create it out of nothing.
    4. What did the Demiurge "take over"? Plato speaks of the "Receptacle - as it were, the nurse of all Becoming." Later he describes this as "Space, which is everlasting, not admitting destruction; providing a situation for all things which come into being, but itself apprehended without the senses by a sort of bastard reasoning, and hardly an object of belief." This Space is not the matter out of which the primary elements are made, but that in which they appear. Plato remarks that the four elements (earth, water, air and fire) cannot be spoken of as substances, since they are constantly changing. They are qualities, which make their appearance in the Receptacle. Thus the Demiurge "took over" (1) the Receptacle, and (2) the primary qualities, which appear in the Receptacle and which the Demiurge fashions or builds up after the model of the Forms. The Demiurge proceeds to confer geometrical shapes on the four primary elements or qualities, forming elementary solids or particles, which may be transformed into one another.
    5. The Demiurge is depicted as creating the World-Soul. The World-Soul is a self-moving initiator of change having the world as its internal environment, like man's soul has a body. Immortal souls are also fashioned by the Demiurge from the same ingredients as the World-Soul. Thus the World-Soul and all immortal souls share in both worlds - in the unchanging world, inasmuch as they are immortal and unchanging, and in the changing world, inasmuch as they are living and changing. The stars and planets have intelligent souls which are the celestial gods, made by the Demiurge and having assigned to them the office of fashioning the mortal part of the human soul and the human body. Plato takes an agnostic position as regards the existence of the anthropomorphic gods, but he does not reject them outright.
    6. Plato defines Time as the moving image of eternity. The Demiurge, having constructed the universe, sought to make it still like its pattern, the Living Creature or Being. Now, the latter is eternal, but "this character it was not possible to confer completely on the generated things. But he took thought to make a certain moving image of eternity; and, at the same time that he ordered the Heaven, he made, of eternity that abides in unity, an everlasting likeness moving according to number - that which we have named Time." Time is the movement of the sphere, and the Demiurge gave man the bright Sun to afford him a unit of time. Its brightness, relative to that of the other celestial bodies, enables man to differentiate day and night.