Kant’s attempt to prove the validity of morality for human agents from merely theoretical premises in the last section of the Groundwork (1785) is generally considered a “spectacular trainwreck” in the literature. The common view is that Kant’s “deduction” suffers from a circular reasoning: his claim that moral considerations ought to always take precedence over non-moral (or prudential) considerations presupposes a prior commitment to morality.

I argue that Kant might have a path out of the “circle”. The key to that path is what I call the “authenticity thesis”. Accordingly, i) one can best identify with moral motivational grounds as belonging to their most authentic self; ii) any rational being, who is capable of a conception of self, would be existentially oriented toward placing higher importance or value on more authentic ways of being than less authentic ones, regardless of whether they act on this recognition.