"It appears to me to be so," said Cebes.
"Is it not most probable, then, that things which are always the same, and in the same state, are uncompounded, but that things which are constantly changing, and are never in the same state, are compounded?"
"To me it appears so."
"Let us return, then," he said, "to the subjects on which we before discoursed. Whether is essence itself, of which we gave this account that it exists, both in our questions and answers, always the same, or does it sometimes change? Does equality itself, the beautiful itself, and each several thing which is, ever undergo any change, however small? Or does each of them which exists, being an unmixed essence by itself, continue always the same, and in the same state, and never undergo any variation at all under any circumstances?"
"They must of necessity continue the same and in the same state, Socrates," said Cebes.
[63]. "But what shall we say of the many beautiful things, such as men, horses, garments, or other things of the kind, whether equal or beautiful, or of all things synonymous with them? Do they continue the same, or, quite contrary to the former, are they never at any time, so to say, the same, either with respect to themselves or one another?"
"These, on the other hand," replied Cebes, "never continue the same."
"These, then, you can touch, or see, or perceive by the other senses; but those that continue the same, you can not apprehend in any other way than by the exercise of thought; for such things are invisible, and are not seen?"
"You say what is strictly true," replied Cebes.
[64]. "We may assume, then, if you please," he continued, "that there are two species of things; the one visible, the other invisible?"