Empedocles’ The Testimonia, Volume II

Love and Strife prevail by necessity and by turns, with rest between.

Aristotle, Physics Θ 1, 252a7

It seems that Empedocles too would say that it belongs to Love and Strife by necessity to prevail and to cause motion by turns, and that in the time between they are at rest.

Report, cautiously framed — Aristotle writes "it seems that he would say", not "he says".

The hedge matters and is kept. This is a principal piece of evidence for a period of rest between the phases of the cycle, and it is offered by Aristotle as an inference about what Empedocles would have to hold, not as a quotation.

Why a second principle was needed: the presence of evil and disorder in nature.

Aristotle, Metaphysics A 4, 984b32

But since the contraries of the goods were also seen to be present in nature — not order and beauty only but disorder and ugliness too, and more evils than goods and more mean things than fair — accordingly another thinker introduced Love and Strife, each of them the cause of one of these. For if ... ... if one follows the argument out and takes it by its sense rather than by the stammering way Empedocles puts it, one will find Love the cause of good things and Strife the cause of evil. So that if one were to say that Empedocles in a way both speaks of evil and good as principles, and was the first to do so, one would perhaps be speaking rightly — if indeed the cause of all goods is the good itself.

Criticism.

"the stammering way Empedocles puts it" (ψελλίζεται) is Aristotle's standing complaint about the Presocratics: they have hold of something but cannot articulate it. He uses the same figure of Anaxagoras. It is worth keeping visible, because the moral reading of Love and Strife that follows is Aristotle's construction on a poet he has just called inarticulate.

the closing bracketed clause is absent from one branch of the tradition; Alexander had it.