Again, truth should be highly valued; if, as we were saying, a lie is useless to the gods, and useful only as a medicine to men, then the use of such medicines should be restricted to physicians; private individuals have no business with them.
It was Plato, according to Sosigenes, who set this as a problem for those concerned with these things, through what suppositions of uniform and ordered movements the appearances concerning the movements of the wandering heavenly bodies could be preserved.
A man who is good for anything ought not to calculate the chance of living or dying; he ought only to consider whether in doing anything he is doing right or wrong - acting the part of a good man or of a bad.
To the rulers of the state then, if to any, it belongs of right to use falsehood, to deceive either enemies or their own citizens, for the good of the state: and no one else may meddle with this privilege.
But he who has been earnest in the love of knowledge and of true wisdom, and has exercised his intellect more than any other part of him, must have thoughts immortal and divine. If he attain truth, and in so far as human nature is capable of sharing in immortality, he must altogether be immortal.