nes had degenerated into a mixed and
mystical view, in which the physical, the metaphysical, and the moral
were confounded together; and that, as the necessary consequence of such
a state, the principles of knowledge were becoming unsettled, a
suspicion arising that all philosophical systems were untrustworthy, and
a general scepticism was already setting in.

To this result also, in no small degree, the labours of Democritus of
Abdera tended. He had had the advantages derived from wealth in the
procurement of knowledge, for it is said that his father was rich enough
to be able to entertain the Persian King Xerxes, who was so gratified
thereby that he left several Magi and Chaldaeans to complete the
education of the youth. On his father's death, Democritus, dividing with
his brothers the estate, took as his portion the share consisting of
money, leaving to them the lands, that he might be better able to devote
himself to travelling. He passed into Egypt, Ethiopia, Persia, and
India, gathering knowledge from all those sources.

[Sidenote: Democritus asserts the untrustworthiness of knowledge.]

According to Democritus, "Nothing is true, or, if so, is not certain to
us." Nevertheless, as, in his system sensation constitutes thought, and,
at the same time, is but a change in the sentient being, "sensations are
of necessity true;" from which somewhat obscure passage we may infer
that, in the view of Democritus, though sensation is true subjectively,
it is not true objectively. The sweet, the bitter, the hot, the cold,
are simply creations of the mind; but in the outer object to which we
append them, atoms and space alone exist, and our opinion of the
properties of such objects is founded upon images emitted by them
falling upon the senses. Confounding in this manner sensation with
thought, and making them identical, he, moreover, included Reflexion as
necessary for true knowledge, Sensation by itself being untrustworthy.
Thus, though Sensation may indicate to us that sweet, bitter, hot, cold,
occur in bodies, Reflexion teaches us that this is altogether an
illusion, and that, in reality, atoms and space alone exist.

[Sidenote: He introduces the atomic theory.]

[Sidenote: Destiny, Fate and resistless law.]

Devoting his attention, then, to the problem of perception--how the mind
becomes aware of the existence of external things--he resorted to the
hypothesis that they constantly throw off images of themselves, which