enough for us if the account we have to
give be as probable as any other, remembering that we are but men, and
therefore bound to acquiesce in merely probable results, without looking
for a higher degree of certainty than the subject admits of"--"Timaeus,"
ch. ix.]

Whatever physical truths were within the author's reach, took their
place in the general array: the vacancies were filled up with the best
suppositions admitted by the limited science of the time.[651] And it is
worthy of remark that, whilst proceeding by this "high _a priori_ road,"
he made some startling guesses at the truth, and anticipated some of the
discoveries of the modern inductive method, which proceeds simply by the
observation, comparison, and generalization of facts. Of these prophetic
anticipations we may instance that of the definite proportions of
chemistry,[652] the geometrical forms of crystallography,[653] the
doctrine of complementary colors,[654] and that grand principle that all
the highest laws of nature assume the form of a precise quantitative
statement.[655]

2. It may be expected that a system of physics raised on optimistic
principles will be _mathematical_ rather than experimental. "Intended to
embody conceptions of proportion and harmony, it will have recourse to
that department of science which deals with the proportions in space and
number. Such applications of mathematical truths, not being raised on
ascertained facts, can only accidentally represent the real laws of the
physical system; they will, however, vivify the student's apprehension
of harmony in the same manner as a happy parable, though not founded in
real history, will enliven his perceptions of moral truth."[656]

[Footnote 651: Butler's "Lectures on Ancient Philosophy," vol. ii. p.
157.]

[Footnote 652: "Timaeus," ch. xxxi.]

[Footnote 653: Ibid., ch. xxvii.]

[Footnote 654: Ibid., ch. xlii.]

[Footnote 655: "It is Plato's merit to have discovered that the laws of
the physical universe are resolvable into numerical relations, and
therefore capable of being represented by mathematical
formulae."--Butler's "Lectures on Ancient Philosophy," vol. ii. p. 163.]

[Footnote 656: Butler's "Lectures on Ancient Philosophy," vol. ii. p.
163.]

3. Another peculiarity of such a system will be an impatience of every
merely _mechanical_ theory of the operations of nature.

"The psychology of Plato led him to recognize mind wherever there was
motion, and hence not o