Prolegomena to Any Future Metaphysics

A short restatement of the Critique of Pure Reason, published two years later because, Kant complained, the Critique had been misunderstood, notably by a review that likened it to Berkeley's idealism. The preface credits Hume's analysis of cause and effect with first interrupting Kant's 'dogmatic slumber'. Where the Critique builds its case from first principles, the Prolegomena starts from knowledge we already have and asks how it is possible. After setting out the distinction between analytic and synthetic judgements, it poses three questions: how is pure mathematics possible, how is pure natural science possible, and how is metaphysics in general possible? The answers run through space and time as forms of intuition, the categories as rules that turn perceptions into judgements of experience, and the ideas of reason that tempt us beyond experience. A final part asks how metaphysics could become a science, and an appendix replies to the review.

It is the shortest route into Kant's theoretical philosophy in his own words, and it shows clearly why Hume's problem about causation set the whole project going.