[19] What then are the parts which are imperishable? In the first place, a perfect alienation from pleasure which says, "Let us lie down together," [15] and let us enjoy human enjoyments; secondly, presence of mind combined with fortitude, by means of which the soul separates and distinguishes from one another those things which by vain opinions are accounted good things, as so many dreams, confessing that "the only true and accurate explanations of things are to be found with God;" [16] and that all those imaginings, which exist in the unsteady, puffed up, and arrogant life of those men who are not yet purified, but who delight in those pleasures which proceed from bakers, and cooks, and wine-bearers, are uncertain and indistinct;