fifteen cviii years let the student go down into the den, and command armies, and gain experience of life. 540At fifty let him return to the end of all things, and have his eyes uplifted to the idea of good, and order his life after that pattern; if necessary, taking his turn at the helm of State, and training up others to be his successors. When his time comes he shall depart in peace to the islands of the blest. He shall be honoured with sacrifices, and receive such worship as the Pythian oracle approves.
‘You are a statuary, Socrates, and have made a perfect image of our governors.’ Yes, and of our governesses, for the women will share in all things with the men. And you will admit that our State is not a mere aspiration, but may really come into being when there shall arise philosopher-kings, one or more, who will despise earthly vanities, and will be the servants of justice only. ‘And how will they begin their work?’ 541Their first act will be to send away into the country all those who are more than ten years of age, and to proceed with those who are left. …
Republic VII. INTRODUCTION. At the commencement of the sixth book, Plato anticipated his explanation of the relation of the philosopher to the world in an allegory, in this, as in other passages, following the order which he prescribes in education, and proceeding from the concrete to the abstract. At the commencement of Book VII, under the figure of a cave having an opening towards a fire and a way upwards to the true light, he returns to view the divisions of knowledge, exhibiting familiarly, as in a picture, the result which had been hardly won by a great effort of thought in the previous discussion; at the same time casting a glance onward at the dialectical process, which is represented by the way leading from darkness to light. The shadows, the images, the reflection of the sun and stars in the water, the stars and sun themselves, severally correspond—the first, to the realm of fancy and poetry—the second, to the world of sense—the third, to the abstractions or universals of sense, of which the mathematical sciences furnish the type—the fourth and last to the same abstractions, when seen in the unity of the idea, from which they derive a new meaning and power. The true dialectical process begins with the contemplation of the real stars, and not mere reflections of them, cix and ends with the recognition of the sun, or idea of good, as the parent not only of light but of warmth and growth. To the divisions of knowledge the stages of education partly answer:—first, there is the early education of childhood and youth in the fancies of the poets, and in the laws and customs of the State;—then there is the training of the body to be a warrior athlete, and a good servant of the mind;—and thirdly, after an interval follows the education of later life, which begins with mathematics and proceeds to philosophy in general.
There seem to be two great aims in the philosophy of Plato—first, to realize abstractions; secondly, to connect them. According to him, the true education is that which draws men from becoming to being, and to a comprehensive survey of all being. He desires to develop in the human mind the faculty of seeing the universal in all things; until at last the particulars of sense drop away and the universal alone remains. He then seeks to combine the universals which he has disengaged from sense, not perceiving that the correlation of them has no other basis but the common use of language. He never understands that abstractions, as Hegel says, are ‘mere abstractions’—of use when employed in the arrangement of facts, but adding nothing to the sum of knowledge when pursued apart from them, or with reference to an imaginary idea of good. Still the exercise of the faculty of abstraction apart from facts has enlarged the mind, and played a great part in the education of the human race. Plato appreciated the value of this faculty, and saw that it might be quickened by the study of number and relation. All things in which there is opposition or proportion are suggestive of reflection. The mere impression of sense evokes no power of thought or of mind, but when sensible objects ask to be compared and distinguished, then philosophy begins. The science of arithmetic first suggests such distinctions. There follow in order the other sciences of plain and solid geometry, and of solids in motion, one branch of which is astronomy or the harmony of the spheres—to this is appended the sister science of the harmony of sounds. Plato seems also to hint at the possibility of other applications of arithmetical or mathematical proportions, such as we employ in chemistry and natural philosophy, such as the Pythagoreans and even Aristotle make use of in Ethics cx and Politics, e.g. his distinction between arithmetical and geometrical proportion in the Ethics (Book V), or between numerical and proportional equality in the Politics (iii. 8, iv. 12, &c.).
The modern mathematician will readily sympathise with Plato’s delight in the properties of pure mathematics. He will not be disinclined to say with him:—Let alone the heavens, and study the beauties of number and figure in themselves. He too will be apt to depreciate their application to the arts. He will observe that Plato has a conception of geometry, in which figures are to be dispensed with; thus in a distant and shadowy way seeming to anticipate the possibility of working geometrical problems by a more general mode of analysis. He will remark with interest on the backward state of solid geometry, which, alas! was not encouraged by the aid of the State in the age of Plato; and he will recognize the grasp of Plato’s mind in his ability to conceive of one science of solids in motion including the earth as well as the heavens—not forgetting to notice the intimation to which allusion has been already made, that besides astronomy and harmonics the science of solids in motion may have other applications. Still more will he be struck with the comprehensiveness of view which led Plato, at a time when these sciences hardly existed, to say that they must be studied in relation to one another, and to the idea of good, or common principle of truth and being. But he will also see (and perhaps without surprise) that in that stage of physical and mathematical knowledge, Plato has fallen into the error of supposing that he can construct the heavens a priori by mathematical problems, and determine the principles of harmony irrespective of the adaptation of sounds to the human ear. The illusion was a natural one in that age and country. The simplicity and certainty of astronomy and harmonics seemed to contrast with the variation and complexity of the world of sense; hence the circumstance that there was some elementary basis of fact, some measurement of distance or time or vibrations on which they must ultimately rest, was overlooked by him. The modern predecessors of Newton fell into errors equally great; and Plato can hardly be said to have been very far wrong, or may even claim a sort of prophetic insight into the subject, when we consider that the greater part of astronomy at the present day consists of abstract dynamics, cxi by the help of which most astronomical discoveries have been made.
The metaphysical philosopher from his point of view recognizes mathematics as an instrument of education—which strengthens the power of attention, developes the sense of order and the faculty of construction, and enables the mind to grasp under simple formulae the quantitative differences of physical phenomena. But while acknowledging their value in education, he sees also that they have no connexion with our higher moral and intellectual ideas. In the attempt which Plato makes to connect them, we easily trace the influences of ancient Pythagorean notions. There is no reason to suppose that he is speaking of the ideal numbers at p. 525 E; but he is describing numbers which are pure abstractions, to which he assigns a real and separate existence, which, as ‘the teachers of the art’ (meaning probably the Pythagoreans) would have affirmed, repel all attempts at subdivision, and in which unity and every other number are conceived of as absolute. The truth and certainty of numbers, when thus disengaged from phenomena, gave them a kind of sacredness in the eyes of an ancient philosopher. Nor is it easy to say how far ideas of order and fixedness may have had a moral and elevating influence on the minds of men, ‘who,’ in the words of the Timaeus, ‘might learn to regulate their erring lives according to them’ (47 C). It is worthy of remark that the old Pythagorean ethical symbols still exist as figures of speech among ourselves. And those who in modern times see the world pervaded by universal law, may also see an anticipation of this last word of modern philosophy in the Platonic idea of good, which is the source and measure of all things, and yet only an abstraction. (Cp. Philebus sub fin.).
Two passages seem to require more particular explanations. First, that which relates to the analysis of vision. The difficulty in this passage may be explained, like many others, from differences in the modes of conception prevailing among ancient and modern thinkers. To us, the perceptions of sense are inseparable from the act of the mind which accompanies them. The consciousness of form, colour, distance, is indistinguishable
