"Knowledge, then," continues Socrates, resuming the argument, "cannot be perception; for, after all, it is the soul which perceives, and the senses are merely organs of the body springing from a common centre of life. In fact, we see and hear rather through them than with them. Furthermore, there are certain abstractions which we (that is, the trained and intelligent few) perceive with the eye of reason alone."
Then Theætetus suggests that knowledge may be defined as "true opinion;" but then, says Socrates, the old objection would be raised, that false opinion is impossible; for we must either know or not know, and in either case we know what we know. The reply is, that mistakes are always possible; you may think one thing to be another. Our souls, continues Socrates, using a metaphor which has since passed into a commonplace, are like waxen tablets—some broad and deep, where the impressions made by sight or hearing are clear and indelible; others cramped and narrow, where the impressions from the senses are confused and crowded together; and sometimes the wax itself is soft, or shallow, or impure, and so the impression is soon effaced. Often, too, we put, so to speak, the shoe on the wrong foot, or stamp with the wrong seal; and from these wrong and hasty impressions come false opinions. There can be no mistake when perception and knowledge correspond; but we often have one without the other. I may see an inscription, but not know its meaning; or I may hear a foreigner talk, but not understand a word he says.
But stay, says Socrates—we have been rashly using
