  As both the second critique and the preceding Groundwork for the Metaphysics of Morals make clear, Kant clearly recognizes that in order to act morally, we need to (i) understand the moral law and what it requires of us; (ii) believe that we are in fact free to choose to do what it requires of us rather than to do what all our other motives, which can be subsumed under the rubric of self-love, might suggest to us; (iii) believe that the objectives that morality imposes upon us can actually be achieved, and (iv) have an adequate motivation for our attempt to do what morality requires of us in lieu of the mere desirability of particular goals it might happen to license or even impose in particular circumstances. All of these together constitute the conditions of the possibility of morality. Kant also thinks that at one level all these conditions are satisfied by pure practical reason itself: (i) the very form of pure practical reason gives us the moral law; (ii) the first “fact” of pure practical reason, namely our consciousness of our obligation under this law, implies the reality of our freedom to be moral by means of the principle that we must be able to do what we know we ought to do; (iii) we can postulate by pure practical reason alone that the laws of nature are compatible with the demands of morality because both laws ultimately have a common author; and finally (iv) pure respect for the moral law itself can be a sufficient motivation for us to attempt to carry it out (and attempts to do so have “moral worth” only when that is our motivation). But Kant also recognizes that we are sensuous as well as rational creatures, and need sensuous as well as rational presentation and confirmation of the conditions of the possibility of morality. The task of the third Critique will then be to show how both aesthetic and teleological experience and judgment provide sensuous confirmation of what we do already know in an abstract way, but also need to feel or make palpable to ourselves, namely the efficacy of our free choice of the fundamental principle of morality in the natural world and the realizability of the objectives which that choice imposes upon us, summed up in the concept of the highest good. Specifically, Kant will argue that although in its purest form, the free play of our understanding and imagination that constitutes the experience of natural beauty does not presuppose any judgment of moral value, the very fact of the existence of natural beauty appears to confirm that the world is hospitable to our goals, especially our moral goals, while our experiences of natural sublimity and artistic beauty both involve the free play of our cognitive powers with morally significant ideas, and thus are distinctively aesthetic yet morally significant.