For what may we hope? The thesis of this book is that the third Critique is oriented by the problem of hope. Hope is born of the interests of reason, but these interests can only be met in a sphere of human experience not subject to or born of the demands of reason. Whatever speaks to the interests of hope must do so disinterestedly. What we hope for is that our wills can be efficacious, that the good we do is not in vain but can have real effects in the world. This, though, depends on something that is not subject to our wills, namely how things actually are. Will the world conform? Will nature yield? The stakes of our interest in this are high: Both reason’s, self-consistency and the risk of existential despair are on the line. Kant’s concern for these seems to grow as his career progresses; the third Critique is his most systematic treatment of the maintenance of hope in what can sometimes seem a banal or cruel world.