If Kant had never made the "critical turn" of 1773, would he be worth more than a paragraph in the history of philosophy? Most scholars think not. But in this pioneering book, John H. Zammito challenges that view by revealing a precritical Kant who was immensely more influential than the one philosophers think they know. Zammito also reveals Kant's former student and latter-day rival, Johann Herder, to be a much more philosophically interesting thinker than is usually assumed and, in many important respects, historically as influential as Kant. Relying on previously unexamined sources, Zammito traces Kant's friendship with Herder as well as the personal tensions that destroyed their relationship. From this he shows how two very different philosophers emerged from the same beginnings and how, because of Herder's reformulation of Kant, anthropology was born out of philosophy. Shedding light on an overlooked period of philosophical development, this book is a major contribution to the history of philosophy and the social sciences, and especially to the history of anthropology.