(2) Plato is perfectly aware—and he could hardly be ignorant—that blood is a fluid in constant motion. He also knew that blood is partly a solid substance consisting of several elements, which, as he might have observed in the use of “cupping-glasses,” decompose and die, when no longer in motion. But the specific discovery that the blood flows out on one side of the heart through the arteries and returns through the veins on the other, which is commonly called the circulation of the blood, was absolutely unknown to him.
A further study of the “Timaeus” suggests some afterthoughts which may be conveniently brought together in this place. The topics which I propose briefly to reconsider are (a) the relation of the “Timaeus” to the other dialogues of Plato and to the previous philosophy; (b) the nature of God and of creation (c) the morality of the “Timaeus”:—
(a) The “Timaeus” is more imaginative and less scientific than any other of the Platonic dialogues. It is conjectural astronomy, conjectural natural philosophy, conjectural medicine. The writer himself is constantly repeating that he is speaking what is probable only. The dialogue is put into the mouth of Timaeus, a Pythagorean philosopher, and therefore here, as in the “Parmenides,” we are in doubt how far Plato is expressing his own sentiments. Hence the connection with the other dialogues is comparatively slight. We may fill up the lacunae of the “Timaeus” by the help of the Republic or “Phaedrus”: we may identify the same and other with the πέρας and ἄπειρον of the “Philebus.” We may find in the Laws or in the “Statesman” parallels with the account of creation and of the first origin of man. It would be possible to frame a scheme in which all these various elements might have a place. But such a mode of proceeding would be unsatisfactory, because we have no reason to suppose that Plato intended his scattered thoughts to be collected in a system. There is a common spirit in his writings, and there are certain general principles, such as the opposition of the sensible and intellectual, and the priority of mind, which run through all of them; but he has no definite forms of words in which he consistently expresses himself. While the determinations of human thought are in process of creation he is necessarily tentative and uncertain. And there is least of definiteness, whenever either in describing the beginning or the end of the world, he has recourse to myths. These are not the fixed modes in which spiritual truths are revealed to him, but the efforts of imagination, by which at different times and in various manners he seeks to embody his conceptions. The clouds of mythology are still resting upon him, and he has not yet pierced “to the heaven of the fixed stars” which is beyond them. It is safer then to admit the inconsistencies of the “Timaeus,” or to endeavour to fill up what is wanting from our own imagination, inspired by a study of the dialogue, than to refer to other Platonic writings—and still less should we refer to the successors of Plato—for the elucidation of it.
More light is thrown upon the “Timaeus” by a comparison of the previous philosophies. For the physical science of the ancients was traditional, descending through many generations of Ionian and Pythagorean philosophers. Plato does not look out upon the heavens and describe what he sees in them, but he builds upon the foundations of others, adding something out of the “depths of his own self-consciousness.” Socrates had already spoken of God the creator, who made all things for the best. While he ridiculed the superficial explanations of phenomena which were current in his age, he recognised the marks both of benevolence and of design in the frame of man and in the world. The apparatus of winds and waters is contemptuously rejected by him in the “Phaedo,” but he thinks that there is a power greater than that of any Atlas in the “Best” (“Phaedo” 97 and following; compare Aristotle Metaphysics I 4, 5). Plato, following his master, affirms this principle of the best, but he acknowledges that the best is limited by the conditions of matter. In the generation before Socrates, Anaxagoras had brought together “Chaos” and “Mind”; and these are connected by Plato in the “Timaeus,” but in accordance with his own mode of thinking he has interposed between them the idea or pattern according to which mind worked. The circular impulse (περίωσις) of the one philosopher answers to the circular movement (περιχώρησις) of the other. But unlike Anaxagoras, Plato made the sun and stars living beings and not masses of earth or metal. The Pythagoreans again had framed a world out of numbers, which they constructed into figures. Plato adopted their speculations and improved upon them by a more exact knowledge of geometry. The Atomists too made the world, if not out of geometrical figures, at least out of different forms of atoms, and these atoms resembled the triangles of Plato in being too small to be visible. But though the physiology of the “Timaeus” is partly borrowed from them, they are
