Kant considers it requisite to provide a deduction, or proof of its grounds, for any judgment claiming necessity. However, since the judgment of taste is neither cognitive nor practical, it can draw its necessity from no concepts. Rather, it has a twofold peculiarity: It claims the universality of a singular, not a universal, proposition, and it claims the necessary assent of everyone a priori, but cannot depend on a priori grounds of proof for doing so. Because of what they are, Kant asserts, the explanation of these peculiarities suffices as a deduction. As to the necessity, although the judgment of each individual improves with exercise, at each stage it claims the necessary assent of others. It claims autonomy. If it submitted to external principles, it would be something other than taste. As to quantity, since it judges without a concept, this must always be singular: “This tulip is beautiful,” never “All tulips are beautiful,” since the universal subject term of the latter is a concept and brings the understanding into the process. Obviously, then, no objective principle of taste is possible, and no rule can be given to art. Rather, the principle of taste is the subjective principle of judgment in general, operating on the condition solely of the faculty of judgment itself.

Unlike mere labor or science or commercial handicraft, beautiful art is free. Yet we must be conscious of it as art and not nature, to keep it within the framework that will allow it to please in the mere act of judging. Beautiful art is the work of genius, which is the “innate mental disposition (ingenium) through which nature gives the rule to art.” Genius is an original productive talent, not a capacity for following rules. Its products serve as examples setting standards for others. Natural beauty is a beautiful thing, but artificial beauty is a beautiful representation of a thing. In some beauties, such as the latter, inevitably a concept enters, and enjoyment through reason as well as aesthetic judging enters with it. Taste, but not genius, is a requisite for judging works of beautiful art. Genius is a faculty of presenting aesthetical ideas, representations of the imagination that occasion much thought where no single thought is adequate. This is a particular kind of the play that harmonizes the imagination and the understanding. It goes beyond the limits of experience to find presentations of such completeness that they have no example in nature, presentations that will communicate the aesthetic pleasure to others.

The chief aesthetic problem of Kant’s times was how to controvert seriously matters of taste, as though taste had an objective standard, when we also assert that there is no disputing tastes. Kant cast the problem as an antinomy in the “Dialectic of the Aesthetical Judgment.” The thesis is “The judgment of taste is not based upon concepts, for otherwise it would admit of controversy (would be determinable by proofs).” The antithesis is “The judgment of taste is based on concepts, for otherwise, despite its diversity, we could not quarrel about it (we could not claim for our judgment the necessary assent of others).” The apparent contradiction is resolved when we recognize that “concept” has a different reference in each proposition. A concept may be either determinable or not. The thesis refers to determinable concepts; the antithesis refers to the one indeterminable concept, the supersensible, on which the faculty of judgment rests. So understood, both are true, and the contradiction disappears.

The beautiful is the symbol of the morally good, in that it gives pleasure with a claim for the agreement of everyone else. It makes the mind feel an elevation of itself above mere pleasantness of sensation and enables it to estimate the worth of others in this regard also. For just as the reason does in respect to the practical, the judgment gives the law to itself with respect to objects of pure aesthetic satisfaction. The propaedeutic to the beautiful arts lies in humane studies, not in precepts, and it reaches art through the social spirit and the communication that is distinctive of humanity. Taste “is at bottom a faculty for judging of the sensible illustration of moral ideas.”