any true word by which that or anything else can be described. Of course
Protagoras would not have admitted the justice of this argument any more
than Heracleitus would have acknowledged the 'uneducated fanatics' who
appealed to his writings. He might have said, 'The excellent Socrates has
first confused me with Heracleitus, and Heracleitus with his Ephesian
successors, and has then disproved the existence both of knowledge and
sensation. But I am not responsible for what I never said, nor will I
admit that my common-sense account of knowledge can be overthrown by
unintelligible Heraclitean paradoxes.'

IV. Still at the bottom of the arguments there remains a truth, that
knowledge is something more than sensible perception;--this alone would not
distinguish man from a tadpole. The absoluteness of sensations at each
moment destroys the very consciousness of sensations (compare Phileb.), or
the power of comparing them. The senses are not mere holes in a 'Trojan
horse,' but the organs of a presiding nature, in which they meet. A great
advance has been made in psychology when the senses are recognized as
organs of sense, and we are admitted to see or feel 'through them' and not
'by them,' a distinction of words which, as Socrates observes, is by no
means pedantic. A still further step has been made when the most abstract
notions, such as Being and Not-being, sameness and difference, unity and
plurality, are acknowledged to be the creations of the mind herself,
working upon the feelings or impressions of sense. In this manner Plato
describes the process of acquiring them, in the words 'Knowledge consists
not in the feelings or affections (pathemasi), but in the process of
reasoning about them (sullogismo).' Here, is in the Parmenides, he means
something not really different from generalization. As in the Sophist, he
is laying the foundation of a rational psychology, which is to supersede
the Platonic reminiscence of Ideas as well as the Eleatic Being and the
individualism of Megarians and Cynics.