Kant's Moral World offers a detailed defense of Immanuel Kant's practical metaphysics. While Kant is widely recognized for his moral philosophy, this study reveals how his ethical framework also serves as a foundation for answering some of the most profound metaphysical questions: Are we truly free? Do we have immortal souls? Can we rationally believe in God? Through a careful and systematic interpretation of Kant's critical works, the book grounds his approach to these questions in the broader development of the concept of pure reason, which begins in the Critique of Pure Reason and stretches through the Groundwork and Critique of Practical Reason . Jessica Tizzard argues that our practical cognition of the moral law and transcendental freedom exemplifies pure reason's real use, which ultimately explains the primacy of practical over theoretical reason. This primacy, in turn, provides rational grounds for affirming the existence of the soul and God as necessary conditions for the realization of a moral world, encapsulated in Kant's idea of the highest good. Combining rigorous textual analysis with philosophical clarity, this monograph offers a compelling new interpretation of Kant's metaphysical project. It invites scholars and students alike to reconsider the depth and coherence of Kant's vision, where morality and metaphysics are not separate domains, but mutually reinforcing aspects of human reason.