  Moreover, for each antinomy in the Critique of Pure Reason, Kant derives both thesis and antithesis by deductive argument from alleged a priori premises. But, in the Antinomy of Teleological Judgment, he does not take that route. This makes quite pressing the question of his justification for the two R-claims above. As to the R-thesis, one might think that it can be easily deduced from Kant’s three Laws of Mechanics. However, we must remember that those laws are constitutive principles, whereas the R-thesis is regulative. A better interpretive avenue is that Kant’s three laws constrain the spectrum of particular empirical laws, including laws for biology, that scientists may seek. The constraint is that the Laws of Mechanics are basic: no other laws of material nature explain or ground them, while they must explain all other laws, directly or indirectly. So, for biological regularities to be turned into genuine laws, they must be integrable with the system of already known mechanical laws, and ultimately explained by the three Laws of Mechanics, the basis for all “interconnected experiential cognition” (5: 386). Even less well understood is Kant’s justification for the R-antithesis. Not only is there no official proof, it is not easy to know what the proof must establish. The R-thesis strongly implies that at issue is the origin of organisms; in contrast, the R-antithesis is about judging their possibility, which has to do with structure and functioning not production (Ginsborg 2001, 236). These are different aspects of organisms, and proving that they are mechanically inexplicable would require different arguments.