The origin of life upon the earth is accounted for by germs
which existed in the atmosphere, and which were brought
down into the terrestrial slime by rain water, and there fruc-
tified. Anaxagoras’s theory of perception is the opposite of
the theories of Empedocles and the Atomists. Perception
takes place by unlike matter meeting unlike.
Anaxagoras owes his importance in the history of philoso-
phy to the theory of the Nous. This was the first time that
a definite distinction had been made between the corpo-
real and incorporeal. Anaxagoras is the last philosopher of
the first period of Greek philosophy. In the second chapter,
[Footnote 9] I observed that this first period is characterized
by the fact that in it the Greek mind looks only outward
upon the external world. It attempts to explain the op-
erations of nature. It had not yet learned to look inward
upon itself. But the transition to the introspective study
of mind is found in the Nous of {104} Anaxagoras. Mind
is now brought to the fore as a problem for philosophy. To
find reason, intelligence, mind, in all things, in the State, in
the individual, in external nature, this is the characteristic
of the second period of Greek philosophy. To have formu-
lated the antithesis between mind and matter is the most
important work of Anaxagoras.
[Footnote 9: Pages 23-4.]
Secondly, it is to the credit of Anaxagoras that he was the
first to introduce the idea of teleology into philosophy. The
system of the Atomists formed the logical completion of the
(ii.) The theory of knowledge
seeks to explain all things by causes. But, as we saw, cau-
sation can explain nothing. The mechanism of the world
shows us by what means events are brought about, but it
does not explain why they are brought about at all. That
can only be explained by showing the reason for things, by
exhibiting all process as a means towards rational ends. To
look to the beginning (cause) of things for their explanation
is the theory of mechanism. To look to their ends for ex-
planation of them is teleology. Anaxagoras was the first to
have dimly seen this. And for this reason Aristotle praises
him, and, contrasting him with the mechanists, Leucippus
and Democritus, says that he appears like “a sober man
among vain babblers.” The new principle which he thus
introduced into philosophy was developed, and formed the
central idea of Plato and Aristotle. To have realized the
twin antitheses of matter and mind, of mechanism and tele-
ology, is the glory of Anaxagoras.But it is just here, in the development of these two ideas,
that the defects of his system make their appearance.
Firstly, he so separated matter and mind that {105} his
philosophy ends in sheer dualism. He assumes the Nous
and matter as existing from the beginning, side by side,
as equally ultimate and underived principles. A monistic
materialism would have derived the Nous from matter, and
a monistic idealism would have derived matter from the
Nous. But Anaxagoras does neither. Each is left, in his
theory, an inexplicable ultimate mystery. His philosophy
is, therefore, an irreconcilable dualism.Secondly, his teleology turns out in the end to be only a new
theory of mechanism. The only reason which induces him
to introduce the Nous into the world, is because he can-