It would be a mistake to try and reconcile these differing modes of thought. They are not to be regarded seriously as having a distinct meaning. They are parables, prophecies, myths, symbols, revelations, aspirations after an unknown world. They derive their origin from a deep religious and contemplative feeling, and also from an observation of curious mental phenomena. They gather up the elements of the previous philosophies, which they put together in a new form. Their great diversity shows the tentative character of early endeavours to think. They have not yet settled down into a single system. Plato uses them, though he also criticises them; he acknowledges that both he and others are always talking about them, especially about the Idea of Good; and that they are not peculiar to himself (“Phaedo” 100 B; Republic VI 505; “Sophist” 248 and following). But in his later writings he seems to have laid aside the old forms of them. As he proceeds he makes for himself new modes of expression more akin to the Aristotelian logic.
Yet amid all these varieties and incongruities, there is a common meaning or spirit which pervades his writings, both those in which he treats of the ideas and those in which he is silent about them. This is the spirit of idealism, which in the history of philosophy has had many names and taken many forms, and has in a measure influenced those who seemed to be most averse to it. It has often been charged with inconsistency and fancifulness, and yet has had an elevating effect on human nature, and has exercised a wonderful charm and interest over a few spirits who have been lost in the thought of it. It has been banished again and again, but has always returned. It has attempted to leave the earth and soar heavenwards, but soon has found that only in experience could any solid foundation of knowledge be laid. It has degenerated into pantheism, but has again emerged. No other knowledge has given an equal stimulus to the mind. It is the science of sciences, which are also ideas, and under either aspect require to be defined. They can only be thought of in due proportion when conceived in relation to one another. They are the glasses through which the kingdoms of science are seen, but at a distance. All the greatest minds, except when living in an age of reaction against them, have unconsciously fallen under their power.
The account of the Platonic ideas in the “Meno” is the simplest and clearest, and we shall best illustrate their nature by giving this first and then comparing the manner in which they are described elsewhere, e.g. in the “Phaedrus,” “Phaedo,” Republic; to which may be added the criticism of them in the “Parmenides,” the personal form which is attributed to them in the “Timaeus,” the logical character which they assume in the “Sophist” and “Philebus,” and the allusion to them in the Laws (XII 964). In the “Cratylus” they dawn upon him with the freshness of a newly-discovered thought (439).
The “Meno” (81 and following) goes back to a former state of existence, in which men did and suffered good and evil, and received the reward or punishment of them until their sin was purged away and they were allowed to return to earth. This is a tradition of the olden time, to which priests and poets bear witness. The souls of men returning to earth bring back a latent memory of ideas, which were known to them in a former state. The recollection is awakened into life and consciousness by the sight of the things which resemble them on earth. The soul evidently possesses such innate ideas before she has had time to acquire them. This is proved by an experiment tried on one of Meno’s slaves, from whom Socrates elicits truths of arithmetic and geometry, which he had never learned in this world. He must therefore have brought them with him from another.
The notion of a previous state of existence is found in the verses of Empedocles and in the fragments of Heracleitus. It was the natural answer to two questions, “Whence came the soul? What is the origin of evil?” and prevailed far and wide in the east. It found its way into Hellas probably through the medium of Orphic and Pythagorean rites and mysteries. It was easier to think of a former than of a future life, because such a life has really existed for the race though not for the individual, and all men come into the world, if not “trailing clouds of glory,” at any rate able to enter into the inheritance of the past. In the “Phaedrus,” as well as in the “Meno,” it is this former rather than a future life on which Plato is disposed to dwell. There the Gods, and men following in their train, go forth to contemplate the heavens, and are borne round in the revolutions of them. There they see the divine forms of justice, temperance, and the like, in their unchangeable beauty, but not without an effort more than human. The soul of man is likened to a charioteer and two steeds, one mortal, the other immortal. The charioteer and the mortal steed are in fierce conflict; at length the animal principle
