One takes hold of this set, another of that set, of literary documents that are available to him or to his time generally; and if he receives from Plato, for example, even quite decisive impulses, so that one later counts him among the Platonists, perhaps he has never, in the crowded course of his philosophical life work, had the time, the possibility, or the desire to study all the Platonic or supposedly Platonic writings, not to speak of the reports or critiques of other thinkers which have an indirect relation to the Platonic philosophy and elucidate it.