The law is simple: treat others as one would want to be treated by them.

Kant résume tout cela dans un principe simple : traiter l’humanité toujours comme une fin, et jamais simplement comme un moyen37.

The cat is responsive to success and failure in her pursuits, but whether the norms that govern her pursuits are valid—whether she ought to behave like a cat or a husky—is not at issue for her. For human beings, by contrast, the validity of norms is always implicitly and potentially explicitly at issue. We act in light of a normative understanding