The book aims to provide a comprehensive study of the ‘Transcendental Dialectic’ of Kant’s first Critique. It argues that Kant conceives of ‘critique’ as a kind of winnowing exercise, aimed to separate the wheat of good metaphysics from the chaff of bad. However, he uses a less familiar metaphor to make this point, namely, that of ‘the fiery test of critique’. This turns out to be, not a medieval ordeal (a trial by fire), but rather a metallurgical assay: so-called ‘cupellation’—a procedure in which ore samples are tested for their precious-metal content. The upshot is that critique has a positive, investigatory side: it seeks not merely to eliminate the dross of bad ‘dogmatic’ metaphysics but also to uncover any hidden nuggets of value that might be contained in traditional speculative metaphysics. There are both gold and silver to be found. The gold is the indirect proof of Transcendental Idealism afforded by the resolution of the Antinomies, the silver Kant’s defence of theoretically grounded ‘doctrinal beliefs’ in a wise and great originator and in an afterlife. In the course of making these points, the book engages with Kant’s views on a number of central problems in philosophy and meta-philosophy, including: the explanation of the enduring human impulse towards metaphysics, correct philosophical method, the limits of self-knowledge, the possibility of human freedom, the resolution of metaphysical paradox (‘Antinomy’), the justification of faith, the nature of scepticism, and the role of ‘as if’ reasoning in natural science.