Philosophy of Plato

Life and Works

Plato was born in Athens in the year 428 or 427 B.C.E. He was of a noble family and was related through his father to Codrus and on his mother's side to Solon. His real name was Aristocles, but he was called Plato by his instructor in gymnastics because of his broad shoulders. Physically perfect, he had an artistic and dialectical temperament which remained with him through his whole life and made of him the philosopher-poet.

He was at first in the school of Cratylus, a follower of Heraclitus and the Sophists, and from him received his start in the study of poetry and an understanding of the philosophers.

At the age of twenty he came under the tutelage of Socrates; he felt profoundly the ethical influence of his master during the eight years he spent in his companionship. During his entire life he remained attached to Socrates, having a profound admiration for him because of the teaching he had received from the master and also because of personal friendship. "I thank the gods for having been born a Greek and not a foreigner, a man and not a woman, free and not a slave, but above all for having been born during the time of Socrates."

We do not know whether Plato was in Athens during the trial of Socrates. It is certain that if not before that time then shortly afterward he left Athens where, after the demise of the great master, the air was not healthy for his disciples. With some friends Plato retired to Megara, to the school of Euclid.

Between 390 and 388 B.C.E. Plato began long voyages in order to place himself in contact with the principal schools which flourished at that time. He visited Egypt, whose venerable antiquity and political stability he admired. He also went to southern Italy, where he was in contact with the Pythagoreans and studied their doctrines. He then went to Sicily and was at the court of Dionysius the Elder, the tyrant of Syracuse. There he formed a friendship with Dion, brother-in-law of the tyrant.

Falling under suspicion Plato was consigned by Dionysius as a prisoner of war to a Spartan ambassador and was then sold into slavery. Freed by a friend in 388 B.C.E., he returned to Athens. There, about the year 387 B.C.E., he founded his famous school, which was called the Academy from the gardens of Academus, where the classes took place. Here Plato imparted his philosophical teachings to his followers. He taught in the Academy for fifty years, that is, until he died.

During this period Plato left Athens twice to go to Syracuse. The first time was in 366 B.C.E. when, after the death of Dionysius, his successor, Dionysius the Younger, and Dion invited him to come there; he went with the hope of carrying out an experiment in his form of the ideal state. When Dion was sent into exile, the deluded philosopher returned to his native city. He returned again to Syracuse in 361 to reconcile Dionysius with Dion. His attempt failed, and he was held a prisoner by Dionysius. Plato was liberated, probably through the intercession of Archytas of Tarentum, general, scientist, and Pythagorean philosopher. After these unhappy attempts, Plato never left Athens again, but became absorbed in his teaching, in metaphysical speculations, and in the editing of his works. Death, which came in 347, interrupted this work. The philosopher was eighty years old.

Plato is one of the most accomplished geniuses humanity has ever known. In him are united the speculative and scientific spirit and the sense of artistic beauty, the influence of which have been felt in all times. All the known works of Plato remain extant, that is, thirty-six dialogues, thirteen letters and a collection of definitions. Critical study casts some doubt on a few -- for example, the definitions, which appear apocryphal, and some of the letters. The most important part of Plato's literary activity is represented by the dialogues, which are authentic in their greater part. In default of the chronological order in which these works were published, they are commonly classified in four groups, representing the various developments of Plato's thought.

They are as follows:

• Socratic Dialogues, youthful writings in which Plato, as yet lacking a personal system of philosophy, expounds and defends the doctrine of Socrates: Laches; Charmides; Euthyphro; Lesser Hippias; Apology for Socrates; Crito; Ion; Lysis.

• Polemical Dialogues against Sophistic doctrine. In these works Sophism is given a concise critical revision under logical, ethical and political aspects, and the doctrine of Socrates defended: Gorgias; Meno; Euthydemus; Cratylus; Theaetetus; Menexenus; Greater Hippias.

• Dialogues of Maturity. Plato, now in complete possession of his system, expounds the theory of the Idea, basis of all his problems: Phaedrus; the Symposium; Phaedo; the Republic.

• Dialogues of Late Maturity, or of his revised teaching: Parmenides; the Sophist; the Statesman; Philebus; Timaeus; Laws.

These dialogues are the most representative of Plato's thought in all its divisions.

Doctrine: General Ideas

Socrates had spoken about concepts, and had affirmed their existence in the field of logic and morality. But he had said nothing of the nature of concepts and of their origin. Plato, his greatest disciple, not only inherited his master's doctrine on concepts, but sought to complete it, giving it a metaphysical foundation. For Plato, the concepts of which Socrates had spoken are representative of a metaphysical world which really exists. This is the world of Ideas; Plato conceives of these Ideas as having all the attributes of the being of Parmenides.

Ideas, for Plato, are subsistent realities, distinct both from the mind that possesses them and the material objects in which they appear. Ideas are eternal, immovable. Opposed to the world of Ideas there is Chaos, the element which receives the form. And between the worlds of Ideas and Chaos there are Demiurge and souls. Demiurge infuses the soul in the Chaos and, working upon it, makes possible this visible world, the world of becoming, of which Heraclitus had spoken.

Another important characteristic of the speculation of Plato, one which he had inherited from Socrates, is that philosophy is conceived of in its practical order. Man must seek the truth; and once the truth is discovered in the purely speculative field, it must serve to find the solution of practical problems: Philosophy must render man morally better. This was the philosophic labor, the quest in which Plato spent his whole noble existence, and it explains the great influence his philosophy has exercised on all ages up to the present day.

Theory of Knowledge

Plato distinguishes four degrees of knowledge:

• Apprehension of pure sense images, such as dreams and imaginations;

• Perceptive knowledge of sensible objects, the purpose of which is to form a particular judgment, such as "This rose is red;...this light is beautiful";

• Mathematical knowledge -- for instance, the apprehension of the particular shape of the perceived rose (Plato observes that mathematical apprehension can be held also independently of any object -- circularity can be apprehended in itself, independently of a circular object);

• Philosophical knowledge, which consists in the apprehension of the Ideas, as absolute, unconditioned and eternal realities.

The first two degrees constitute what Plato calls opinion, because the things appear in this manner, but they could appear also in a different manner. The last two degrees constitute true understanding, because their object is the reality which is, and which cannot be otherwise. (See "The Myth of the Cave" in Plato's Republic, VII, 1-3.)

The four degrees of knowledge may be reduced to two fundamental classes:

• Sense knowledge, which includes apprehension of sensorial images, and perception of sensible objects;

• Intellective knowledge, which includes mathematical notions and knowledge of ideas.

For Plato, the inferior degrees constitute knowledge in so far as they express the necessity of something which transcends them; they are steps through which the soul ascends to the world of Ideas. The soul, which understands that its happiness consists in the world of Ideas, never is satisfied with the knowledge of the inferior degrees. Thus it appeals from the inferior to the superior degrees, till the knowledge of Ideas is reached. This continuous dissatisfaction of the soul is what Plato calls Love or Eros, the god of love. (See "The Myth of Eros" in the Symposium.)

General Metaphysics

The World of Ideas: Plato's investigations begin on the Socratic plan, that is, with sensitive cognition, with the purpose not only of transcending the data of sense and arriving at concepts (a problem already solved by Socrates), but also of going beyond Socratic concepts to the point of reaching a world where concepts are actual realities and not only simple representations.

There are two ways to knowledge: the senses and the intellect. The two kinds of knowledge which result differ essentially: sensitive cognition tells us that a thing is, but does not tell us what that thing is; sensitive cognition shows us the existence but not the essence of the thing known. Consequently sense knowledge is devoid of the characteristics of universality and necessity. On the other hand, intellective (conceptual) knowledge tells us what the object is that we know, and has at the same time the characteristics of necessity and universality.

According to Plato, these two kinds of knowledge are not derivable one from the other. Intellective knowledge does not take its origin from sensitive cognition. First of all, the characteristics of both are diametrically opposed: sensitive cognition is contingent and particular; intellective knowledge is necessary and universal. Since the perfect cannot be derived from the imperfect, intellective knowledge cannot be derived from that which is sensitive.

Moreover, Plato, led by his mathematical and aesthetic studies, finds not only that these concepts cannot be derived from experience, but also that such concepts precede experience. I must, for example, have first the concept of a circle in my mind in order to know whether that particular figure on the blackboard is a circle or not. If the knowledge of just what a circle is (the concept of a circle) were not anterior to the data of the senses (the circle drawn on the board), I would be unable to affirm that the given figure is a circle.

Having affirmed the distinction of inderivability and the precedence of intellective over sensitive knowledge, Plato makes of our concepts more than representative signs; he makes of them a world of actual realities. The Ideas of Plato are endowed with real existence in a world superior to the world which we see, which is the object of sensitive cognition. Ideas as they appear in our own mind are but the images or representations of things in this world apart.

Plato was induced to admit the existence of this world of Ideas from a parallelism which he noted between intellective and sensitive cognition. If sense knowledge presupposes a world constituted of beings and is derived from them, equally so must it be said of intellective knowledge: hence there exists a world of beings (Ideas) from which our ideas draw their representations.

The suprasensible world of Plato must be considered as constituting a multiplicity of subsistent ideas which find their unity in the Idea of the Good (God). Platonic Ideas in fact are but the realities which refract the single Idea (the Good). Granted, then, the identity of the Good and of the True and the Beautiful, all ideas are at the same time true, good and beautiful, i.e., perfect models. The world of Ideas is the world of true reality.

The existence of a transcendent world (Ideas) presents Plato with new and grave problems regarding cosmic and psychic nature. Both the sensible world and the human intellect participate in the world of transcendence, the first under the form of essence and the second under the form of Ideas. How can this participation be understood? In other words, what is the relationship between the sensible world and that of transcendence; why are ideas present in the human mind independently of all contact with the sensible world? The attempt to resolve these new problems forms what we will call the cosmology and the psychology of Plato.

Cosmology

The sensible world is presented to us under a twofold aspect, the first rational, the second irrational, corresponding respectively to form (essence) and matter. Let us take a tree as an example. We know that it is a tree because it has the form of a tree. If we prescind from that form and from any other form whatsoever, what remains? There remains an element without form and hence unintelligible.

Now if we follow this line of abstraction with reference to all things in the sensible world, if we thus prescind from all form, we find ourselves confronting a space without form but filled with formless matter. This is Chaos, Platonic non-being, called such not because it is nothing, but because there is in it no form (intelligible being). These two aspects of sensible reality correspond to two metaphysical states, preexistent to the sensible world. Thus there is had on one hand non-being (chaos, unformed matter) and on the other being (Ideas), co-eternal and opposed to each other. But how are these two opposed worlds united to form this sensible world, which is presented under the aspect of being and non-being?

To resolve this problem Plato has recourse to Demiurge, a divine artificer, the intermediary between unformed matter and the world of Ideas. Demiurge first infuses a soul into matter, by means of which space takes on life and form. Then, with successive infusions of souls, it forms the heavens and the earth. Demiurge is directed in its labor according to the order of the world of Ideas, which are as it were models in ordering the matter.

In this way matter has become a participant in the intelligible world, and through this participation the world of experience is made up of a combination of rational and irrational elements, of being and non-being. Matter, in the order given to it by Demiurge, remains always an opaque, irrational element which tends to resist complete penetration by the form, and hence is the root of multiplicity of beings and also of their imperfections. (Evil takes its origin from matter.) The rational element is represented by the form. But how is the form made present in matter by Demiurge? Plato gives various answers. At times he speaks of the descent of idea into matter; at other times he speaks of imitation.

Psychology

The Soul

We have said that Plato, once having admitted that knowledge of Ideas is anterior to sensitive cognition, is presented with the question of when and how the soul came into possession of this knowledge. To solve this difficulty, Plato has recourse to the Pythagorean theory of preexistence. Souls exist before their bodies, and as Ideas and unformed matter are eternal. From eternity they exist together with Ideas, and it is thus that they have come to know Ideas. Cast out of the ideal world because of some mysterious fault, souls carry within themselves the knowledge of these Ideas (Innatism).

Such knowledge, however, from the very moment the soul was banished from the ideal world and was united to the body, falls into a kind of lethargy. It will be the sensation, as we shall presently see, that shakes the mind from its sleep and brings it once more to the realization of the presence of Ideas within itself. The soul which descends from the invisible world to put on the mortal remains which it must keep for the course of earthly life, finds that the body already has an irrational soul subdivided into two parts: the irascible (impulsive and disdainful), with its seat in the heart; and the consupiscible, residing in the bowels and inclined to the ignoble pleasures of the senses. The rational soul is that which comes from the invisible world and takes its seat in the head. Its union with the body is extrinsic; the body is as it were its tomb, and it must regulate the impulse of the irascible soul and repress the desires of the concupiscible soul if it wishes to live according to reason.

The immortality of the soul is a consequence of the doctrine of the preexistence of souls. If souls existed before the body the latter is not necessary for their existence, and hence with death souls return to live as before this union. In the Phaedo, Plato has other more valid arguments, such as that deduced from the nature of the knowledge of Ideas, from which he deduces the fact that the soul must be by nature similar to Ideas, i.e., simple and not subject to changes.

Cognition as reminiscence

The fundamental grades of cognition are two: sensitive and intellective. The first is bound up with the object which appears to our senses, hence it is bound up with matter, and deprived of all necessity and universality. It generates opinion, which is a knowledge of the particular; it is incapable of being taken as a basis of science, which must transcend the particular and is founded on the necessary and absolute.

Intellective cognition, on the other hand, is real knowledge and forms the basis of science. As we have said, the one is inderivable from the other. Thus sensitive cognition, containing the image (though faded) of the invisible world, offers to the intellective soul the occasion of awakening again in itself knowledge of the Ideas which it already had in the suprasensitive world. The soul, in the presence of the image offered by the senses, acts like a slave who, bound to the door of a cave, recognizes from the shadow projected on the cave's depths whose image the shadow may be. ("The Myth of the Cave," Republic, VII, 1-3.) Intellective cognition for Plato is not the acquisition of new content, but the reawakening of a knowledge already possessed: it is nothing other than reminiscence.

Ethics

The ethics of Plato is an application in practice of the principles which had been reached in the metaphysical field. We know that the soul, which was happy in the contemplation of the ideal world, now finds itself imprisoned in the body and impelled by the pleasures of sense. To give in to these impulses would mean to strengthen yet more the bonds with matter and to render oneself ever more distant from true happiness, which is in the world of Ideas.

Reason wills, therefore, that the soul overcome the obstacles which render it unworthy of participating again in the ideal world and living according to reason. The soul can be compared to the driver of a chariot drawn by two horses, one fast and the other slow: it is the duty of the driver to restrain the first and to urge on the second. These two horses are the two aspects of the irrational soul, the irascible and concupiscible. The driver, the rational soul, must restrain the first from its inconsiderate impulses, and must incite the second to good whenever it stops before the pleasures of sense.

Mastery over irascible and concupiscible impulses gives origin to two virtues, fortitude and temperance. One who is strong tempers the impulses of anger and eager enthusiasm; he who is temperate moderates the pleasures of the senses by bringing them under the dominion of reason. The actuation of fortitude and temperance is not possible without a third virtue, namely, justice. Justice is fundamental in Plato's philosophy in so far as, granted the destiny of the soul, justice wills that during the course of earthly life the rational soul must live by dominating the two aspects of the irrational soul without being overcome by them. All three of the virtues mentioned, justice, fortitude and temperance, have their origin in a fourth, wisdom, the contemplation of the truth of the ideal world, which is in itself virtue and happiness.

This wisdom which is now found sleeping in the soul must be aroused through the images of it which are found in sensible things, and from sensible things it must arise to the invisible and supreme beauty, which is nether born nor dies. (Symposium.) In so far as we draw near to the contemplation of this supreme beauty, by so much are we separated from the illusory life. Hence Plato calls philosophy "the contemplation of death."

Regarding the destiny of souls after death, Plato is dependent not only on his philosophy but also on the Orphic-Dionysian mysteries. In general he distinguishes three classes of souls:

• Those that have committed inexpiable sins, and hence are condemned forever;

• Those that have committed expiable sins;

• Those living according to justice.

Souls in the last two categories are reborn and reincarnated in order to receive their due punishment or reward. According to Phaedo, a fourth class of souls must be added, that of the philosophers, seers of the idea, who are free forever from the temporal life.

Politics

The politics of Plato are the rigid application of all that he had already recognized as true in metaphysics and ethics. He does not regard the empirical reality which surrounds him, the various constitutions of Grecian cities, but has in view the ideal world which is the norm of the true and the good and hence of every virtue. He traces the lines of a republic in which men must be organized in such a way that they may realize to the maximum extent that which it is given them to know of the ideal world. And animated by the conviction that material reality must be sacrificed to the ideal, Plato is not brought to a stop even by those consequences which at first sight seem paradoxes, such as the partial abolition of property and of the family.

Although Plato treats of state organization in Politics and in Laws, his fundamental treatise is the ten books of the Republic. His thought can be summarized as follows:

First of all Plato finds that the necessity for society and the state resides in human nature itself. No one is sufficient in himself; everyone needs the aid of others in order to live a life worthy of man. Hence man must live with others in society in order to make use of them both materially and morally.

From the moment society arises out of the necessity of meeting the needs of man, the members which make up society must be organized into different classes according to the diversity of works to be be performed. Led by the theory that in man there are two different souls, one of which has two aspects, Plato establishes the teaching that in society also there must be three different organizations or classes: philosophers, warriors, and producers, corresponding to the rational soul and the two aspects of the irrational soul (the irascible and the concupiscible).

Each of these classes has its special work to fulfill:

• The philosophers must direct the state;

• The warriors must defend the state;

• The producers (subdivided into various groups of arts and skills) must attend to the material production of those things that are needed by the state.

Thus Plato's state is eminently aristocratic. Its direction is confided to a few philosophers who, granted the Platonic identification of wisdom and virtue, are also the best and hence are worthy of directing all the others.

The philosophers, who live in the contemplation of the ideal world, are, in the state, the representatives of wisdom, which is the fundamental virtue, as we have seen. The philosophers, because they are wise, also know the essence of the state and can show the other two classes the way that must be followed in order to attain the end of the state. They must restrain the warriors from their irrational impulses, and thus there arises rational fortitude; they must restrain the passions and greed of the producers; this restraint gives rise to the virtue of temperance. Thus is attained the virtue of justice, which we know to be, after wisdom, the fundamental virtue of human life.

The state must also take care of education in order to procure new leaders. Practically speaking, education is restricted to the warrior class, from which the (philosophers) were elected to the head of the state. The producers' class is not considered because of the Greek prejudice against manual labor. Education comprises music and gymnastics, the first to render the spirit amiable; music includes not only music properly speaking, but also poetry, history, and so forth -- all the activities presided over by the Muses. Hence the name "music." Gymnastics serves to render the body shapely and strong, and must be subordinated to music because physical development, if not regulated by the mind, produces unmannerly and materialistic people. Hence Plato has a certain aversion to physical exercise.

The state thus thought out by Plato is an ethico-religious organism which must care for the material good of the citizens and above all lead them to the attainment of the ideal of virtue. The citizens of Plato's state must concern themselves with living in accord with the transcendent world and not give in to the inclinations of sense and passion. The great personage is not the one who does great things, but the one who knows how to live wisely.

Plato is ready to sacrifice everything. Thus he denied the family and the right of private property to the philosopher and warrior classes. He understood that attachment to one's own family and greed for material goods could be grave impediments preventing these two classes from fulfilling their duty, in view of the fact that the latter have to defend the state even at the cost of their lives and the former have to live completely in the contemplation of virtue. In Plato private property and the family find place only in the class called producers.

To see Plato as the precursor of present-day Socialism and Communism is to misconstrue his entire ethical teaching. He denied the family and the right to property to two classes in the state because these classes must be completely freed from the shackles of material goods and intent on attaining a grade of spiritualization. On the contrary, Socialism and Communism of the present day deny private property and would abolish the institution of the family for a thoroughly materialistic purpose, that is, to make possible greater material prosperity.

Art

In Book X of the Republic, Plato strives to prove that art is a secondhand imitation (a shadow of a shadow) of being and of good, but that only the wise (the philosophers) have a knowledge of these. He concludes that, with the exception of lyric poetry in honor of the gods and heroes, art has no place in the well-organized state. Art, according to Plato, is a copy of empirical reality. A bed which the artist reproduces upon canvas is only a copy of a bed which he finds in the multiplicity of nature, and this in turn is a copy of a bed in se which exists in the world of Ideas.

Poetry, both because of its unrealistic content (Homer represents Zeus as a bird, and the souls of the deceased as a swarm of bees), and because of its end, which is to excite the passions that have their seat in the concupiscible soul, is an imitation which is far from the true and the good; hence poetry must be banished from a well-organized city, where men must live in such a way as to ascend to the ideal world.

It is the usual preoccupation with morals which induces Plato to condemn art in so far as he sees in it the danger of corruption rather than a means of elevation. But as an artist-philosopher, Plato could understand that art is not a simple imitation, a reproducing of empirical reality. In the Symposium he affirms that art is a mania, a divine madness which places the artist above the common run of man, and he concludes that a person who does not have this divine influence knocks in vain at the door of art.

Religion

In the Republic, Plato compares the Idea of the Good to the sun, as the supreme cause of all knowledge and existence. As the multiplicity of individuals is unified in the respective Ideas, in the same manner the multiplicity of Ideas is unified in the Idea of the Good. Hence in the Platonic system the Idea of the Good is the supreme reality on which all other ideas and all ethical, logical and aesthetic values of the sensible world depend. The Idea of the Good is the reality through which the world of becoming is made possible and rational. Thus it is truly the god of Plato.

But the Idea of the Good has neither personality nor the power of creating. According to Plato, Demiurge is the divine artificer which forms the heavens and the earth by successive infusions of souls. Demiurge, however, cannot be identified with God, for if he is superior to matter, he is inferior to ideas, which furnish the model he uses to arrange matter and transform Chaos in the visible world.

Since God is identified with the impersonal Idea of the Good, which lacks any activity with reference to nature and man. He can be attained only by reason, and the cult of reason is due Him.

Regarding popular religion, Plato is opposed to anthropomorphism. So greatly is he opposed to it that, as we have seen, he wished to banish the poets, not excepting Homer, from the ideal state on account of the fantastic and immoral myths with which they represent the gods. He is not opposed, however, to a form of astral polytheism in which a multitude of gods subject to Demiurge animates the stars and the cosmic universe. These are the visible gods which Plato wishes to substitute for rough and uncouth Grecian mythology.

Insufficiencies of Plato's System

The problem which most troubled the mind of Plato was that which had already been posed by the Pre-Socratics: the being of Parmenides and the becoming of Heraclitus. Plato attempted a reconciliation of these by introducing the world of Ideas, which should have given a rational explanation of both systems of thought.

The being of Parmenides would be the ideal world, intelligible, the supreme Good. But differing from Parmenides, who held this being to be one, solid, and massive, Plato breaks it up, we might say, into the multiplicity of Ideas, whose unity lies in their relation to the supreme Good.

Now along with this logico-metaphysical being, Plato advances another, non-being, which is co-eternal with Ideas. This is a metaphysical dualism such as is found in all Greek philosophers in the absence of a concept of creation. According to Plato, Demiurge should be the artificer which is able to find the answer to Heraclitus' problem of becoming. Plato places Demiurge before matter (non-being, opposing the intelligible, the necessary), in order that the descent of Ideas might be effected. The intelligible, through the operation of Demiurge, is imposed upon non-being. However, the non-being, the origin of evil, is never completely overcome by the intelligible. The metaphysics of Plato is essentially dualistic: the good (Ideas), and the evil (non-being). Plato unsuccessfully attempts to explain the becoming of Heraclitus by a penetration of the irrational by the rational, of matter by the intelligible.

From this dualism it follows that evil is a metaphysical and insuppressible necessity. Cosmic reality is a struggle between good and evil, between Demiurge and non-being. In the face of the impenetrability of non-being, Demiurge must be declared impotent.

Certainly no one has felt more than Plato the religious significance of the world and of life. However, a false notion of non-being, uncreated and co-eternal, the origin of evil, has impeded the philosopher from attaining a completely rational and religious vision of man and of nature. Plotinus was to attempt to overcome this difficulty, which would finally be answered in St. Augustine.

The Academy

The Academy, the philosophic school founded by Plato, lasted about a thousand years after him -- until the sixth century after Christ. It is usually divided into three periods:

• The Ancient Academy occupies the century immediately after the death of the master. It numbered among its members men of outstanding influence and doctrine, such as Speusippus and Arcesilaus.

• The Middle Academy is predominantly Skeptic. Carneades (214-129 B.C.E.) is the predominant representative of this tendency. He denied the possibility, in the speculative field, of attainting truth; and in the practical order he defended the sufficiency of probabilism.

• The New Academy, which endured until the beginning of the era of dissolution of Grecian culture, returned to the ancient dogmatism, with particular sympathy for Eclecticism and Pythagoreanism.

But the Academy survived also these tendencies of the New Academy, and assumed its ultimate form in Neo-Platonism, which represents the last grandiose effort of Greek thought to solve the philosophical problem, by developing dualism into emanative pantheism.