Ought, Can, Reason

Some contemporary Deontic Logicians study a thesis that they attribute to Kant--Ought implies Can.  However, both the Logical status of the thesis, and the attribution, are problematic.  To begin with, if Can has any Modal meaning, it is Possibility.  But the formulation Ought implies Possibility conflates Deontic Logic and Modal Logic, and, hence, as is, is meaningless in either.  Now, Kant does assert the thesis, but as an expression of principles that seem well beyond the scope of its putative adaptation.  To begin with, their example of the case of someone who cannot repay a loan because of dire financial straits is irrelevant to Kant's derivation of Ought on the grounds that a false-promise Maxim cannot be Universalized.  So, the citing of that example indicates a lack of recognition that Kant's Ought is specifically one of Reason.  Likewise, there seems to be no recognition that for Kant, the motivator is not Ought per se, but Ought for Ought's sake, the ground of which is Reason for Reason's sake.  But of great significance to him is that acting on Reason for Reason's sake, as opposed to merely obeying Reason, entails voluntarily giving oneself Reason, i. e. Autonomy, and it is insofar as Reason creates this option that is the source of a Can.  So, the attribution, by some Deontic Logicians, of 'Ought implies Can' to Kant, abstracts the Deontic Morality dimension of his doctrine from its Rational Ethics dimension.