Spontaneity - understood as an action of the mind or will that is not determined by a prior external stimulus - is a theme that resonates throughout Immanuel Kant's theoretical and practical philosophy. Though spontaneity and the concomitant notion of freedom lie at the foundation of many of Kant's most pivotal theses and arguments regarding cognition, judgment, and moral action, spontaneity and freedom themselves often remain cloaked in mystery, or accessible only via transcendental argument. This volume brings together a distinguished group of scholars who explore the nature of freedom and spontaneity, the arguments Kant offers surrounding these concepts, and their place in Kant's larger philosophical system. The collection will be of interest to scholars interested in any aspect of Kant's philosophy, especially those who hope to gain a deeper insight into these fundamental Kantian ideas.