h. Do you
think of accusing Anaxagoras, Miletas, and have you so low an opinion of
these men, and think them so unskilled in laws, as not to know that the
books of Anaxagoras the Clazomenaean are full of these doctrines.
And forsooth the young men are learning these matters from me which
sometimes they can buy from the orchestra for a drachma, at the most,
and laugh at Socrates if he pretends they are his-particularly seeing
they are so strange."

The element of error contained in these cosmogonic speculations of
Anaxagoras has led critics to do them something less than justice. But
there is one other astronomical speculation for which the Clazomenaean
philosopher has received full credit. It is generally admitted that it
was he who first found out the explanation of the phases of the moon;
a knowledge that that body shines only by reflected light, and that its
visible forms, waxing and waning month by month from crescent to disk
and from disk to crescent, merely represent our shifting view of its
sun-illumined face. It is difficult to put ourselves in the place of
the ancient observer and realize how little the appearances suggest the
actual fact. That a body of the same structure as the earth should shine
with the radiance of the moon merely because sunlight is reflected
from it, is in itself a supposition seemingly contradicted by ordinary
experience. It required the mind of a philosopher, sustained, perhaps,
by some experimental observations, to conceive the idea that what seems
so obviously bright may be in reality dark. The germ of the conception
of what the philosopher speaks of as the noumena, or actualities,
back of phenomena or appearances, had perhaps this crude beginning.
Anaxagoras could surely point to the moon in support of his seeming
paradox that snow, being really composed of water, which is dark, is in
reality black and not white--a contention to which we shall refer more
at length in a moment.

But there is yet another striking thought connected with this new
explanation of the phases of the moon. The explanation implies not
merely the reflection of light by a dark body, but by a dark body of a
particular form. Granted that reflections are in question, no body but
a spherical one could give an appearance which the moon presents. The
moon, then, is not merely a mass of earth, it is a spherical mass of
earth. Here there were no flaws in the reasoning of Anaxagoras. By
scientific induction he passed f