(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 after-thoughts 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 connexion 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 (Greek) 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