In Metaphysics E. 3. 1027a29-30 Aristotle states that there are some causes, the incidental ones, that are generable and destructible but they have no coming to be. Furthermore, he asserts that if we deny this thesis, then we will have to give into determinism (1027a30-32). There are three persistent puzzles surrounding this chapter. First, what does it mean to say that a cause is generable and destructible but it has no coming to be? Second, what exactly is the connection between this claim and determinism? And third, if we accept that in Metaphysics E. 3 Aristotle deals with incidental causation, then how is this discussion related to the treatment of incidentalness in E. 2? This article puts forward answers for these puzzles. I argue that there is textual evidence in Physics II. 5 that shows that the claim in Metaphysics 1027a29-30 is meant to capture the non-teleological nature of incidental causation. Moreover, I argue that this same textual evidence indicates that the thesis expressed at Metaphysics 1027a29-30 is in effect Aristotle's response to teleological determinism. Finally, I suggest that it is plausible to suppose that chapter 3 does not quite belong with the rest of Metaphysics E.