Timaeus — Plato

to a higher knowledge. He never reflects, how great a thing it was to have formed a conception, however imperfect, either of the human frame as a whole, or of the world as a whole. According to the view taken in these volumes the errors of ancient physicists were not separable from the intellectual conditions under which they lived.

Their genius was their own ; and they were not the rash and hasty generalizers which, since the days of Bacon, we have been apt to suppose them. The thoughts of men widened to receive experience; at first they seemed to know all things as in a dream : after a while they look at them closely and hold them in their hands. They begin to arrange them in classes and to connect causes with effects.

General notions are necessary to the apprehension of particular facts, the metaphysical to the physical. Before men can observe the world, they must be able to conceive it.

To do justice to the subject, we should consider the physical philosophy of the ancients as a whole ; we should remember, (i) that the nebular theory was the received belief of several of the early physicists; (2) that the development of animals out of fishes who came to land, and of man out of the animals, was held by Anaximander in the sixth century before Christ (cp. Plut. Symp. Quaest. viii. 8. 4; Plac. Phil. v.

19. i) ; (3) that evenby Philolaus and the early Pythagoreans, the earth was held to be a body like the other stars revolving in space around the sun or a central fire ; (4) that the beginnings of chemistry are discernible in the * similar particles' of Anaxagoras.

Also they knew or thought (5) that there was a sex in plants as well as in animals; (6) they were aware that musical notes depended on the relative length or tension of the strings from which they were emitted, and were measured by ratios of number; (7) that mathematical laws pervaded the world ; and even qualitative differences were supposed to have their origin in number and figure ; (8) the annihilation of matter was denied by several of them, and the seeming disappearance of it held to be a transformation only.

For, although one of these discoveries might have been supposed to be a happy guess, taken together they seem to imply a great advance and almost maturity of natural knowledge. We should also remember, when we attribute to the ancients hasty generalizations and delusions of language, that physical 2philosophy and metaphysical too have been guilty of similar Thnaeus. fallacies in quite recent times. We by no means distinguish Introducclearly between mind and body, between ideas and facts. Have ^'°'* not many discussions arisen about the Atomic theory in which a point has been confused with a material atom ? Have not the natures of things been explained by imaginary entities, such as life or phlogiston, which exist in the mind only ?

Has not disease been regarded, like sin, sometimes as a negative and necessary, sometimes as a positive or malignant principle? The ' idols' of Bacon are nearly as common now as ever; they are inherent in the human mind, and when they have the most complete dominion over us, we are least able to perceive them. We recognize them in the ancients, but we fail to see them in ourselves.

Such reflections, although this is not the place in which to dwell upon them at length, lead us to take a favourable view of the speculations of the Timaeus. We should consider not how much Plato actually knew, but how far he has contributed to the general ideas of physics, or supplied the notions which, whether true or false, have stimulated the minds of later generations in the path of discovery.

Some of them may seem old-fashioned, but may nevertheless have had a great influence in promoting system and assisting enquiry, while in others we hear the latest word of physical or metaphysical philosophy. There is also an intermediate class, in which Plato falls short of the truths of modern science, though he is not wholly unacquainted with them, (i) To the first class belongs the teleological theory of creation.

Whether all things in the world can be explained as the result of natural laws, or whether we must not admit of tendencies and marks of design also, has been a question much disputed of late years. Even if all phenomena are the result of natural forces, we must admit that there are many things in heaven and earth which are as well expressed under the image of mind or design as under any other.

At any rate, the language of Plato has been the language of natural theology down to our own time, nor can any description of the world wholly dispense with it. The notion of first and second or co-operative causes, which originally appears in the Timaeus, has likewise survived to our own day, and has been a great peace-maker between theology and science. Plato also approaches very near to our doctrine of the primary and VOL. III. — 42 3secondary qualities of matter (6i ff. ). (2) Another popular notion which is found in the Timaeus, is the feebleness of the human intellect — ' God knows the original qualities of things ; man can only hope to attain to probability. We speak in almost the same words of human intelligence, but not in the same manner of the uncertainty of our knowledge of nature.

The reason is that the latter is assured to us by experiment, and is not contrasted with the certainty of ideal or mathematical knowledge. But the ancient philosopher never experimented : in the Timaeus Plato seems to have thought that there would be impiety in making the attempt ; he, for example, who tried experiments in colours would ' forget the difference of the human and divine natures ' (68 D).

Their indefiniteness is probably the reason why he singles them out, as especially incapable of being tested by experiment. (Compare the saying of Anaxagoras — Sext. Pyrrh. i. 33 — that since snow is made of water and water is black, snow ought to be black. ) The greatest ' divination ' of the ancients was the supremacy which they assigned to mathematics in all the realms of nature ; for in all of them there is a foundation of mechanics.

Even physiology partakes of figure and number ; and Plato is not wrong in attributing them to the human frame, but in the omission to observe how little could be explained by them. Thus we may remark in passing that the most fanciful of ancient philosophies is also the most nearly verified in fact. The fortunate guess that the world is a sum of numbers and figures has been the most fruitful of anticipations.

The ' diatonic ' scale of the Pythagoreans and Plato suggested to Kepler that the secret of the distances of the planets from one another was to be found in mathematical proportions. The doctrine that the heavenly bodies all move in a circle is known by us to be erroneous ; but without such an error how could the human mind have comprehended the heavens?

Astronomy, even in modern times, has made far greater progress by the high a priori road than could have been attained by any other. Yet, strictly speaking — and the remark applies to ancient physics generally — this Ya^ a priori road was based upon a posteriori grounds. For there were no facts of which the ancients were so well assured by experience as facts of number. Having observed that they held good in a few