  It appears that all of the Arguments in D6 are valid. Like the Arguments of the first five Deductions, the Arguments of D6 rest on a number of independent premises, including premises of D5 (but not D1, D2, D3, D4, or the Appendix). Again, it appears that most of the premises are, at least from Plato’s point of view, either definitionally true or just plain obvious. Thus it appears that, from Plato’s point of view, D6 establishes, without reliance on Purity-F or any other potentially problematic assumption, that if the one is not, then the one has neither of a host of contrary properties.