  In chapter 6 of his Tractatus Theologico-Politicus, Baruch Spinoza sets out to argue for the claim that nature cannot be contravened, but that she “preserves a fixed and immutable course,” in consequence of which a miracle is “a sheer absurdity” (Spinoza 1670/1862: 123, 128). His argument for this claim is somewhat difficult to follow, but it appears to run approximately like this: