Kant's System of Freedom and Nature: The Third Critique. The Critique of the Power of Judgement ('Third Critique') seeks to transform the two great divisions of Kant's thought – the theory of nature presented in the Critique of Pure Reason, and the theory of freedom presented in Kant's practical works – into a unified philosophical system. The importance of this task for Kant and the difficulty that it poses are considerable. It is vital that the distinction of freedom and nature not be collapsed, since without it morality will be confused with empirical knowledge and nature with things in themselves, yet Kant's dualism generates a problem that, he makes clear, must be solved, for we cannot coherently regard ourselves in the same breath as members of two disjointed worlds, the one empirical and the other intelligible. Kant seeks accordingly in the Third Critique to show that his dualism can be mediated without being dismantled, and that the result has sufficient coherence for the purposes of human reason. This involves the introduction of major new elements, and the extension of Kant's philosophy to two areas not previously treated, namely aesthetics and biology. Their common significance, Kant argues, is that they disclose a purposiveness in nature, a meaning in appearances, that transcends natural scientific knowledge and lends the world an aspect of human intelligibility, whereby we find ourselves at home in it.

The course is divided into three parts. Part One is devoted to making clear Kant's need to provide a mediation of freedom and nature. In the first week (which will provide those who have not studied Kant previously with a background for what follows) we look at the 'great chasm', as Kant calls it, separating the domains of freedom and nature, and at contemporary critics of his dualism. The second week examines Kant's philosophy of history, in which we see his commitment to interpreting history both as a natural process, hence as subject to empirical law, and as answering to the interests of human freedom. This raises in a new form, which Kant has not yet elucidated, the question of how such a double view is possible.

Part Two looks at the main divisions of the Third Critique, the Critique of the Aesthetic Power of Judgement, and the Critique of the Teleological Power of Judgement. We begin with Kant's account of judgements of taste. The key to attributions of beauty to objects lies, Kant proposes, in the special harmony of our cognitive powers that they occasion, a state of 'free play' of imagination and understanding, yielding a pure pleasure in which the subject registers the object's 'form of purposiveness'. Kant next sets the sublime in opposition to the beautiful. The objects we call sublime are distinguished by their formlessness and defy assimilation by our mental powers, but the mixture of pain and pleasure that defines sublimity is also, according to Kant, an experience of nature's purposiveness, albeit of a 'negative' kind. We then look at Kant's proto-romantic theory of fine art, and his interpretation of the beautiful as a 'symbol' of the supersensible.

In the Critique of the Teleological Power of Judgement Kant attempts to do justice to the difference of organic from inorganic nature, and our conceptualization of the former as purposively organized. In defending natural teleology, Kant must walk a fine line between affirming that there is (contra the Darwinian world-view) more to nature than mechanistic causality, and readmitting (contra Aristotelians and deists) dogmatic metaphysics. We look first at Kant's analysis of the appearance that organisms give of a species of form that transcends mechanism, and then at his use of transcendental idealism to reconcile the purposiveness of organic nature with mechanistic explanation.

Returning to the original question of how nature and freedom can be unified, in Part Three we look at the two places in the text where Kant gives his explicit answer to the question. First, Kant formulates in the Introduction to the Third Critique an original and complex hypothesis, which supplements his earlier teachings, namely that our power of judgement, like our other rational powers, has an a priori principle of its own. The principle in question is that of nature's purposiveness for our cognition. In the final week we consider the concept introduced late in the Third Critique of the 'intuitive intellect', described by Kant as a mode of cognition in which the dualities constitutive of human reason are transcended and the whole is apprehended prior to its parts. We have no knowledge of the intuitive intellect, just as we have no knowledge of God, but the Idea thereof is necessary for us. Though intended by Kant to bring to a conclusion his argument with Spinoza – whose monism Kant regarded as the precise antithesis of his own standpoint, and as its strongest competitor – the concept of the intuitive intellect stimulated Kant's major idealist successors to regard the Third Critique not as a systematic end point but as the basis for new philosophical construction.

The Third Critique contains therefore an aesthetic theory and a biological theory, each of which can be taken on their own. Considered as a whole, the work represents the consummation of Kant's system and provided the springboard for German Idealism, while Kant's problem of reconciling freedom and nature endures to the present day.

The weekly readings consist of manageable extracts from the Critique of the Power of Judgement. The course is designed in such a way that, as a cumulative picture of Kant's system builds up, each weekly topic can be understood as concerned with an independent philosophical problem.

Philosophy Area C