Having analyzed Kant's conception of agency in Groundwork II and seen how the introduction of autonomy modifies the earlier, first Critique conception, we are finally in a position to consider his moral psychology. Although this psychology underwent a significant development in the writings from the Groundwork to the Metaphysics of Morals, its basic elements are already in place in the former work. Thus, it is here that we find the familiar, yet frequently criticized account of a good will as one motivated by the thought of duty alone, with the consequent disparagement of inclination as a potential source of moral worth. Closely related to this is the doctrine of reverence or respect (Achtung) for the law as the only genuine moral motive, which Kant sketches in the Groundwork and develops in much greater detail in the Critique of Practical Reason. These are the topics of the present chapter, which is therefore divided into two parts.

A good will and moral worth

Groundwork I begins with Kant's famous proclamation that “it is impossible to conceive anything at all in the world, or even out of it, which can be taken as good without qualification except a good will” (Gr 4: 393; 61). This claim, which Kant himself presents as an expression of the universal judgment of ordinary human reason, has been frequently criticized; but our concern is not so much with the cogency of the claim itself as with the analysis of the goodness of a good will.