Note (return) — Chapter IX

Parmenides of Elea (born B.C. 536) was the philosopher who framed the psychological opinions of the Idealist school into a precise and comprehensive system. He was the first carefully to distinguish between Truth (ἀλήθειαν) and Opinion (δοξαν)--between ideas obtained through the reason and the simple perceptions of sense. Assuming that reason and sense are the only sources of knowledge, he held that they furnish the mind with two distinct classes of cognitions--one variable, fleeting, and uncertain; the other immutable, necessary, and eternal. Sense is dependent on the variable organization of the individual, and therefore its evidence is changeable, uncertain, and nothing but a mere "seeming." Reason is the same in all individuals, and therefore its evidence is constant, real, and true. Philosophy is, therefore, divided into two branches--Physics and Metaphysics; one, a science of absolute knowledge; the other, a science of mere appearances. The first science, Physics, is pronounced illusory and uncertain; the latter, Metaphysics, is infallible and immutable. 450