(_β_) Aristotle also says in criticizing further the relationship and determination of these two universal principles of Friendship and Strife, as of union and separation, that “Empedocles neither adequately made use of them nor discovered in them what they involved (_ἐξευρίσκει τὸ ὁμολογούμενον_); for with him friendship frequently divides and strife unites. That is, when the All falls asunder through strife amongst the elements, fire is thereby united into one, and so is each of the other elements.” The separation of the elements which are comprised within the All, is just as necessarily the union amongst themselves of the parts of each element; that which, on the one hand, is the coming into separation, as independent, is at the same time something united within itself. “But when everything through friendship goes back into one, it is necessary that the parts of each element undergo separation again.” The being in one is itself a manifold, a diverse relation of the four diversities, and thus the going together is likewise a separation. This is the case generally with all determinateness, that it must in itself be the opposite, and must manifest itself as such. The remark that, speaking generally, there is no union without separation, no separation without union, is a profound one; identity and non-identity are thought-determinations of this kind which cannot be separated. The reproach made by Aristotle is one that lies in the nature of the thing. And when Aristotle says that Empedocles, although younger than Heraclitus, “was the first to maintain such principles, because he did not assert that the principle of motion is one, but that it is different and opposed,” this certainly relates to the fact that he thought it was in Empedocles that he first found design, although his utterances on the subject were dubious. (_γ_) As to the real moments in which this ideal realizes itself, Aristotle further says, “He does not speak of them as four”—equivalents in juxtaposition—“but on the contrary as two; fire he puts by itself on the one side, and the three others, earth, air, and water, on the other.” What would be most interesting is the determination of their relationship. (_δ_) In what deals with the relationship of the two ideal moments, friendship and strife, and of the four real elements, there is thus nothing rational, for Empedocles, according to Aristotle (Met. XII. 10), did not properly separate, but co-ordinated them, so that we often see them in proximity and counted as having equal value; but it is self-evident that Empedocles also separated these two sides, the real and the ideal, and expressed thought as their relation.