aginary 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. (1) 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 secondary qualities of matter.
(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 r