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Plato (plāˈtō), 427?–347 B.C., Greek philosopher. Plato's teachings have been among the most influential in the history of Western civilization.


After pursuing the liberal studies of his day, he became in 407 B.C. a pupil and friend of Socrates. From about 388 B.C. he lived for a time at the court of Dionysius the Elder, tyrant of Syracuse. On his return to Athens, Plato founded a school, the Academy, where he taught mathematics and philosophy until his death. His teaching was interrupted by two more visits to Syracuse (367 and 361 B.C.), which he made in the vain hope of seeing his political ideals realized in Sicily.

Works and Philosophy

Plato was a superb writer, and his works are part of the world's great literature. His extant work is in the form of dialogues and epistles. Some of the dialogues and many of the epistles attributed to him are known to be spurious, while others are doubtful. In the various dialogues he touched upon almost every problem that has occupied subsequent philosophers. The dialogues are divided into three groups according to the probable order of composition.

Early Works

The earliest group of dialogues, called Socratic, include chiefly the Apology, which presents the defense of Socrates; the Meno, which asks whether virtue can be taught; and the Gorgias, which concerns the absolute nature of right and wrong. These early dialogues present Socrates in conversations that illustrate his main ideas—the unity of virtue and knowledge and of virtue and happiness. Each dialogue treats a particular problem without necessarily resolving the issues raised.

Philosophical Themes and Mature Works

Plato was always concerned with the fundamental philosophical problem of working out a theory of the art of living and knowing. Like Socrates, Plato began convinced of the ultimately harmonious structure of the universe, but he went further than his mentor in trying to construct a comprehensive philosophical scheme. His goal was to show the rational relationship between the soul, the state, and the cosmos. This is the general theme of the great dialogues of his middle years: the Republic, Phaedo, Symposium, Phaedrus, Timaeus, and Philebus. In the Republic he shows how the operation of justice within the individual can best be understood through the analogy of the operation of justice within the state, which Plato proceeds to set out in his conception of the ideal state. However, justice cannot be understood fully unless seen in relation to the Idea of the Good, which is the supreme principle of order and truth.

It is in these dialogues that the famous Platonic Ideas (see realism) are discussed. Plato argued for the independent reality of Ideas as the only guarantee of ethical standards and of objective scientific knowledge. In the Republic and the Phaedo he postulates his theory of Forms. Ideas or Forms are the immutable archetypes of all temporal phenomena, and only these Ideas are completely real; the physical world possesses only relative reality. The Forms assure order and intelligence in a world that is in a state of constant flux. They provide the pattern from which the world of sense derives its meaning.

The supreme Idea is the Idea of the Good, whose function and place in the world of Ideas is analogous to that of the sun in the physical world. Plato saw his task as that of leading men to a vision of the Forms and to some sense of the highest good. The principal path is suggested in the famous metaphor of the cave in the Republic, in which man in his uninstructed state is chained in a world of shadows. However, man can move up toward the sun, or highest good, through the study of what Plato calls dialectic. The supreme science, dialectic, is a method of inquiry that proceeds by a constant questioning of assumptions and by explaining a particular idea in terms of a more general one until the ultimate ground of explanation is reached.

The Republic, the first Utopia in literature, asserts that the philosopher is the only one capable of ruling the just state, since through his study of dialectic he understands the harmony of all parts of the universe in their relation to the Idea of the Good. Each social class happily performs the function for which it is suited; the philosopher rules, the warrior fights, and the worker enjoys the fruits of his labor. In the Symposium, perhaps the most poetic of the dialogues, the path to the highest good is described as the ascent by true lovers to eternal beauty, and in the Phaedo the path is viewed as the pilgrimage of the philosopher through death to the world of eternal truth.

Late Works

Many of the late dialogues are devoted to technical philosophic issues. The most important of these are the Theaetetus; the Parmenides, which deals with the relation between the one and the many; and the Sophist, which discusses the nature of nonbeing. Plato's longest work, the Laws, written during his middle and late periods, discusses in practical terms the nature of the state.


See translation of the dialogues by B. Jowett, ed. by D. J. Allan and H. E. Daley (4 vol., 4th ed., rev. 1953); A. E. Taylor, Plato: The Man and His Work (1927); R. Bambrough, ed., New Essays on Plato and Aristotle (1965); G. Vlastos, Platonic Studies (1973); G. F. Else, Plato and Aristotle on Poetry (1987); Jacob A. Kline, A Commentary on Plato's Meno (1989); C. Hampton, Pleasure, Knowledge, and Being: An Analysis of Plato's Philebus (1990); J. E. G. Evans, A Plato Primer (2010).

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(play -toh) See table at craters.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006


(428-348 BC) major Greek philosopher, pupil of SOCRATES, and teacher of ARISTOTLE. Living most of his life in Athens, Plato contributed to many areas of PHILOSOPHY, and his ideas exerted a many-sided influence on Western social thought, e.g. on political science, and on theories of education. The most fundamental feature of Plato's philosophical thinking is his theory of‘forms’, in which observable reality, constantly in flux and in decay, is regarded as a departure from pure forms or ‘ideas’, e.g. the idea ‘triangle’ or the idea ‘horse’, which are ‘necessary’ and unchanging. Plato was impressed by the apparent certainties of mathematics, which led him to posit a realm of pure ideas – immaterial but nonmental, and known by intuition rather than empirical inquiry. Such IDEALISM permeates Plato's social and political writings as much as his more purely philosophical thought. It is exemplified in his best-known work The Republic, written, like much of his work, as a series of dialogues, in which a pure form of polity is outlined. In this ideal republic, philosophers, as the wisest and the best, would rule, employing censorship in education, and requiring the obedience of the majority. A connection between Plato's authoritarianism and Plato's idealism has been suggested by theorists such as POPPER.
Collins Dictionary of Sociology, 3rd ed. © HarperCollins Publishers 2000


(religion, spiritualism, and occult)

Plato, the most famous of all Greek philosophers, lived in Athens from approximately 427 b.c.e. to 347 b.c.e. Although some sources have claimed that Plato lived for a period in Egypt and studied astrology, this is not reflected in his writings. Plato’s significance for astrology is that directly through his own surviving works and indirectly through the Neoplatonic tradition, he was the most influential advocate of the idea that the human being is a miniature version (microcosm) of the larger universe (macrocosm). The microcosm and the macrocosm are linked by—and affect each other through—certain correlations. This notion is basic to ancient astrology.

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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



Born 428 or 427 B.C., in Athens; died there 348 or 347 B.C. Ancient Greek philosopher.

Plato was born into an aristocratic family. In circa 407 he met Socrates and became one of his most enthusiastic pupils. After the death of Socrates, Plato went to Megara. According to tradition, he visited Cyrene and Egypt. In 389 he went to southern Italy and Sicily, where he associated with the Pythagoreans.

Plato founded his own school in Athens (Plato’s Academy). In 367 and 361 he again visited Sicily. In 361 he went there at the invitation of the ruler of Syracuse, Dionysius the Younger, who had expressed his intention of putting Plato’s political ideas into practice. Like Plato’s previous attempts to establish contact with men in power, this trip ended in complete failure. Plato spent the remainder of his life in Athens, where he wrote a great deal and delivered lectures.

Almost all of Plato’s works are dialogues, most of which are conducted by Socrates. In language and composition the dialogues are distinguished for their high literary quality. The early period of Plato’s work (roughly the 390’s B.C.) is represented by the Apology, Crito, Euthyphro, Laches, Lysis, Charmides, Protagoras, and Book 1 of the Republic. The Socratic method of analyzing particular concepts is presented in these dialogues, which are dominated by moral questions. Associated with a transitional period (the 380’s B.C.) is another group of works, including the Gorgias, Meno, Euthydemus, Cratylus, and Hippias Minor, which contain the embryo of the theory of ideas and criticize the relativism of the Sophists. The mature period of Plato’s work (370’s and 360’s B.C.) is represented by the Phaedo, Symposium, and Phaedrus; Books 2–10 of the Republic (the theory of ideas); and the Theaetetus, Parmenides, Sophist, Politi-cus, Philebus, Timaeus, and Critias. In these works Plato shows an interest in problems of structure and logic and presents his theory of epistemology, as well as the dialectics of categories and of the cosmos. The late period of the philosopher’s work (350’s B.C.) is represented by the Laws

Plato’s philosophy is not expounded systematically in his works, which strike the modern scholar as a vast laboratory of thought. Thus, the Platonic system has to be reconstructed. Its most important parts are the theory of the three basic ontological substances (the One, the Intellect, and the Soul) and the related theory of the cosmos. According to Plato, the basis of all being is the One, which in itself is devoid of attributes and parts, has neither beginning nor end, does not occupy space, and cannot move, because motion requires change (that is, plurality). Among the attributes that cannot be applied to the One are identity, difference, and similarity. Nothing can be said of the One, which is higher than all being, sensation, and thinking. Concealed in this source (the One) are not only the ideas (forms, or eide) of things (that is, their substantial spiritual prototypes and principles, to which Plato ascribes an extratemporal reality), but also things themselves and their coming into being, or becoming.

In Plato’s theory the second substance, the Intellect (nous), which is generated by the One (or the Good), consists of being and light. The Intellect, which is pure and unmixed, is carefully differentiated by Plato from everything that is material, physical, and going through the process of becoming: the Intellect is intuitive, and its object is the essence of things, not their becoming. The dialectical conception of the Intellect is completed with a cosmological concept: the Intellect is the generic, mental generalization of all living beings, as well as a living entity, or life itself as manifested in ultimate generalization, order, perfection, and beauty. The Intellect is embodied in the cosmos—specifically, in the regular and eternal movement of the heavens.

The third substance, or World Soul, unites the Intellect and the corporeal world. The Soul receives the laws of its movement from the Intellect, from which it differs in its perpetual mobility —the principle of self-movement. The Intellect is incorporeal and immortal. The Soul, which is immortal and is associated with the truth and the eternal ideas, unites the Intellect with the corporeal world by means of something beautiful, proportioned, and harmonious. The individual soul is the image and outflow of the World Soul. Plato spoke of the immortality or, more precisely, the eternal rejuvenation of the body together with the soul. Death is the transition of the body to another state.

The ideas are the ultimate generalization, meaning, and meaningful essence of things, as well as the very principle by which they are apprehended. Ideas possess not only a logical but also a certain artistic structure. Inherent in them is their own ideal matter, the shaping of which permits them to be comprehended aesthetically. The beautiful also exists in the ideal world as the embodiment of an idea—the ultimate form and intellectual anticipation of all possible approximations of an idea. The beautiful is, in a sense, an organism of an idea, or, more precisely, the idea as an organism. Further dialectical development of the prototype leads to the intellect, soul, and body of the cosmos, resulting in the creation of beauty in its final form for the first time. The cosmos, which perfectly reproduces the eternal prototype or pattern (“paradigm”), is more beautiful than anything else. This doctrine is closely related to the Platonic theory of cosmic proportions.

For Plato, matter is only the principle of a partial functioning of an idea—its abridgment, diminution, or obscuring. Matter is a “receptacle” and “nurse” for ideas. In itself, it is absolutely formless, containing neither earth, water, air, nor any other physical element. Matter is not being; only the ideas are being. Sharply criticizing the separation of ideas from things, Plato formulated the very arguments that Aristotle later directed against alleged Platonic dualism. For Plato, genuine being is ideal being, which exists in itself and is merely “present” in matter. Matter first comes into existence by imitating, associating with, or “participating” in ideal being.

In the last years of his life Plato revised his teaching about the ideas in conformity with Pythagoreanism, seeking the source of the ideas in “ideal numbers.” This trend in his thought was important in the development of Neoplatonism.

The foundation of Plato’s theory of epistemology is the ecstasy of love for the idea. Thus, ecstasy and cognition prove to be an indissoluble whole. With brilliant artistry, Plato depicted the ascent from physical love to love in the realm of souls, and from there to the realm of pure ideas. He interpreted the synthesis of love (eros) and cognition as a special kind of rapture and ecstasy, or erotic enthusiasm, and he gave a mythological description of cognition as the soul’s remembrance of its heavenly birthplace, where it apprehended every idea directly.

For Plato, the basic science that determines all other fields of knowledge is the dialectic—a method of dividing the one into many, of reducing the many to one, and of providing a structural representation of the whole as the many in one. Entering the realm of confused things, the dialectic divides and separates them so that each receives its own meaning and its own idea. The meaning or idea of a thing is taken as the principle of the thing, as its “hypothesis,” its law {nomos), which, according to Plato, leads from diffuse sensibility to an ordered idea, and vice versa. This is precisely the meaning of the “Logos” in Plato’s work. The dialectic, therefore, is a method of establishing the intellectual foundations of things, their objective a priori categories or conceptual forms. The progression from Logos to idea to hypothesis to foundation is also regarded as the limit (the “aim”) of sensory becoming, a universal aim that appears as the Good in the Republic, Philebus, and Gorgias and as Beauty in the Symposium. The limit on the realization (the becoming) of a thing contains a condensed version of the entire formative process of a thing and serves as its blueprint and structure. Thus, Plato’s dialectic is also a theory of indivisible wholes, and as such, it is simultaneously discursive and intuitive. The dialectic can perform all possible logical divisions and at the same time combine everything into one. According to Plato, the dialectician possesses the “combined vision” of the sciences and “sees all at one time.”

The individual soul possesses three capacities—the intellectual, the volitional, and the emotional, of which the first has primacy. In Plato’s ethics there are three corresponding virtues: wisdom, courage, and an illuminated emotional state. They are united into one complete virtue, justice, which represents the equilibrium of its three components.

A similar triadic division is found in Plato’s political thought, in the theory of the three estates: philosophers, who govern on the basis of their contemplation of the ideas; warriors, whose main goal is to defend the state from internal and external enemies; and laborers (peasants and artisans), who give the state material support by supplying it with vital resources. Plato distinguished three principal forms of government: monarchy, aristocracy, and democracy. Each is further subdivided into two forms. A monarchy may be lawful (headed by a king) or based on force (headed by a tyrant). Aristocracy may be the rule of the best or the rule of the worst (oligarchy). Democracy may be lawful or unlawful (based on force). Plato sharply criticized all six forms of government and presented an ideal, Utopian model for state and social organization. According to Plato, kings should be philosophers, and philosophers should be kings. But only a few contemplators of the truth could qualify for this role. Plato developed a detailed theory of social and personal upbringing for the philosophers and warriors, but he did not make it applicable to the “laborers.” He called for the abolition of private property, for the communal sharing of wives and children, for the state regulation of marriages, and for the public upbringing of children, who were not to know the identity of their parents. K. Marx described the utopia presented in Plato’s Republic as “the Athenian idealization of the Egyptian system of castes” (K. Marx and F. Engels, Soch, 2nd ed., vol. 23, p. 379).

In Plato’s aesthetics, beauty is understood as the absolute interpenetration of body, soul, and mind and as the blending of idea and matter, of reason and pleasure, with proportion serving as the guiding principle. Plato does not separate cognition from love or love from beauty (the Symposium, Phaedrus). Thus, all beauty—seen and heard, external or physical—is animated by its own internal life and contains some meaning. Plato regarded beauty in this sense as the ruling force and the source of life for all living things.

For Plato, the beauty of life and real being is superior to that of art. Being and life are the imitation of external ideas; art, an imitation of being and life, is an imitation of an imitation. Consequently, Plato banished Homer from the ideal republic, even though he had greater regard for him than for any other Greek poet. The ideal state was to be a creation of life and not of fantasies, however beautiful. Plato also banned sad, enervating, and Anacreontic music from the ideal state, permitting only martial, courageous, or calming music. Morality and decency are considered necessary conditions for beauty.

Although he did not reject the gods of traditional mythology, Plato demanded that they be philosophically purged of crude, immoral, and fantastic elements. He believed that most of the myths should not be studied by children at an impressionable age. Myth, according to Plato, is symbol. He used mythology to present the periods and ages of the cosmos, the cosmic movement of the gods and of souls in general, and similar phenomena.

Plato is historically important as a philosopher because he consistently thought through the basic principles of objective idealism. Thus, V. I. Lenin termed the entire idealist line in philosophy “the line of Plato” (Poln. sobr. soch, 5th ed., vol. 18, p. 131). Plato’s ideas served as the starting point for a tradition of Platonism and Neoplatonism that has lasted many centuries.


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In Plato’s Apologia and Symposium, the philosopher viewed dreams as a channel through which the gods communicated to people.



Plato (c. 429–347 B.C.E.) was born of a family who had long played a considerable part in Athenian politics. He declined to follow the same course, however, because he was disgusted by the corruption of political life in Athens, which was among the causes of the execution in 399 of Socrates, his friend and teacher. The death of Socrates encouraged Plato to protect and preserve his memory by writing dramatic conversations in which Socrates employed the same methods of argument that he had used when he was alive.

Plato dedicated the rest of his life to philosophy, convinced that it was the only cure for the ills of society, which would never cease unless philosophers became rulers or rulers became philosophers. He traveled broadly, especially to Sicily, and in Athens founded the Academy, an institution devoted to the study of philosophy.

Although Plato did not discuss dreams at any length, using them rather as a structure for symbolic action and philosophical speculation, various passages of some of his dialogues report his observations about this phenomenon. In his early dialogues, such as Apologia and Symposium, dreams are regarded as a channel for messages received from the gods and are used as a theological method of acquiring knowledge concerning the gods and their will. An enlightened theology of dreams appears also in the last dialogues, such as Sophistes, in which Plato asserts that all four truly existing realities—human and animal, fire and water—possess their specific images, which are created by the gods and are not the product of the realities themselves. Man’s image, for example, is his dreaming world. In Sophistes, Plato also considers the dream as a philosophical method through which a particular kind of knowledge can be achieved.

A Homeric description of the dream experience prevails in Crito and Phaedo, both about the last days of Socrates. In each dialogue, Socrates attributes great importance to his dreams by following their suggestions. The first dream pictures the land of the soul’s afterlife, whereas in the second dream Socrates speaks of a shift in attention from philosophy to poetry.

Plato gives a definition of the act of dreaming in Politeia, asserting that it means “to take the copy not as a copy, but as reality itself.” According to Plato, in the actual act of dreaming the dreamer does not have the power to associate the dream experience with waking life, thus establishing his firm belief in the reality of his dreams.

According to Plato’s biological theory of dreams, dreams originate in a persistent activity of the respective organs in the belly. The liver, in particular, is described as the biological seat of dreams. Dreaming may be caused either by over-gratification or by frustration of those organs in waking life. Plato maintained that when the rule of reason is suspended in sleep, the other two elements of the soul—desire and anger—and all the repressed aspects of personality break through with all their power, and the soul can accept incest, murder, and sacrilege.

Plato delineates a relationship between ethics and dreams by asserting, in Politeia, Theaitetos, and Nomoi, that even the individual whose life is considered decent may be subject to very unethical dreams, and a man’s dreams are generally indicative of his ethical attitude or the level of his education. He also maintains that a theological explanation can be given for terror dreams, which may be caused by unethical behavior.

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Plato (427–347 B.C.)

founder of the Academy; author of Republic. [Gk. Hist.: NCE, 2165]


(427–347 B.C.) Greek philosopher revered for wisdom. [Gk. Hist.: NCE, 2165]
See: Wisdom
Allusions—Cultural, Literary, Biblical, and Historical: A Thematic Dictionary. Copyright 2008 The Gale Group, Inc. All rights reserved.


?427--?347 bc, Greek philosopher: with his teacher Socrates and his pupil Aristotle, he is regarded as the initiator of western philosophy. His influential theory of ideas, which makes a distinction between objects of sense perception and the universal ideas or forms of which they are an expression, is formulated in such dialogues as Phaedo, Symposium, and The Republic. Other works include The Apology and Laws
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005


(1) (Programmed Logic for Automatic Teaching Operations) Developed by Daniel Alpert and Donald Bitzer at the University of Illinois in 1960, PLATO was the first computer-based training (CBT) system to combine graphics and touch-sensitive screens for interactive training. In the late 1960s, the National Science Foundation (NSF) funded the project, and the Computer-based Education Research Laboratory (CERL) was formed. In the 1970s and 1980s, Control Data Corporation (CDC) donated computers, developed PLATO courseware and created a new division to market it. The investment was not profitable and PLATO was eventually abandoned.

(2) The code name for Microsoft's OLAP extensions to SQL Server. See Microsoft SQL Server OLAP Services.
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'Not that it's any business of yours, but yes, I have,' Plato answered and Rook told him he was not allowed to bring women back to his lodgings - it wasn't that 'type of house'.
We know of his philosophy through his pupil, Plato. Aristotle, who had studied with Plato (indeed he was Plato's most brilliant student, whom Plato nicknamed the Mind), had developed his own enormous body of work, which had a major impact on the philosophy of the Middle Ages and beyond (4).
Goldstein, a novelist and philosopher, pulls off what could have easily veered into the corny or preachy with tact, humor, and, most importantly, a fairness that delves into Plato's ideas without specifically condoning any conclusions, a skill that Plato himself perfected in his dialogues.
Jordan Prater, a former employee at Plato's Closet in Fayetteville, and her husband, Seth, opened the Conway franchise earlier this year, their second location.