  It appears that every Argument of D2 is logically valid. (However, see Gill (1996, 64, n. 107), who contends that D2A8 and D2A9 are fallacious, and Patterson (1999, 98–100), who argues that D2A8 is fallacious.)) Like the Arguments of D1, the Arguments of D2 rest on a large number of independent premises, including many of the independent premises of D1. Again, most of these premises are, at least from Plato’s point of view, either definitionally true or self-evident. (Gill (1996, 83–84) objects to one of the premises of D2A14 and Patterson objects to one of the premises of D2A28, but Rickless (2007, 160 and 175) claims that it is unclear whether Plato himself would have found these premises problematic.) There are three exceptions to this claim: D2A4, D2A12, and D2A14. D2A4 depends on Causality and No Causation by Contraries, D2A12 depends on No Causation by Contraries, and D2A14C depends on D2A12C. But there are reasons for thinking that No Causation by Contraries is false. When combined with Causality, No Causation by Contraries entails that, for any property F, the F cannot be con-F. But, assuming that the one is, this contradicts D2A3C, namely that if the one is, then the one is (infinitely) many. So, if Causality is true and the one is, then No Causation by Contraries must be false. This result is important, for the falsity of No Causation by Contraries would enable Plato to dispatch at least some of Parmenides’ earlier criticisms of the theory of forms, notably the first two criticisms of the result of combining the theory of forms with the Piece-of-Pie Model conception of partaking—see the end of section 4.2 above.