In the history of Grecian philosophy we find no distinct traces of a
pure rational theology earlier than Anaxagoras; but this is not
because the older philosophers had not intelligence or penetration
enough to raise themselves to it by the path of speculation, at
least with the aid of a thoroughly reasonable hypothesis. What could
have been easier, what more natural, than the thought which of
itself occurs to everyone, to assume instead of several causes of
the world, instead of an indeterminate degree of perfection, a
single rational cause having all perfection? But the evils in the
world seemed to them to be much too serious objections to allow them
to feel themselves justified in such a hypothesis. They showed
intelligence and penetration then in this very point, that they did
not allow themselves to adopt it, but on the contrary looked about
amongst natural causes to see if they could not find in them the
qualities and power required for a First Being. But when this acute
people had advanced so far in their investigations of nature as to
treat even moral questions philosophically, on which other nations had
never done anything but talk, then first they found a new and
practical want, which did not fail to give definiteness to their
conception of the First Being: and in this the speculative reason
played the part of spectator, or at best had the merit of embellishing
a conception that had not grown on its own ground, and of applying a
series of confirmations from the study of nature now brought forward
for the first time, not indeed to strengthen the authority of this
conception (which was already established), but rather to make a
show with a supposed discovery of theoretical reason.