Immanuel Kant's work changed the course of modern philosophy; Karl Ameriks examines how. He compares the philosophical system set out in Kant's Critiques with the work of the major philosophers before and after Kant. Individual essays provide case studies in support of Ameriks's thesis that late 18th-century reactions to Kant initiated an "historical turn," after which historical and systematic considerations became joined in a way that fundamentally distinguishes philosophy from science and art.
This is a rich book, and especially the last essay is extremely dense with insight. Ameriks discusses constellation research, in which we locate philosophical ideas in a historical context. We need to find a balance between systematic and ahistorical concerns that seek to find foundationalist principles, and more personal and relativistic concerns that deny absolute truth and root everything in a historical perspective. Ameriks notes that in a post-Kuhnian age we need to be less ambitious than the ahistorical systems of Descartes and Plato, that seek to root metaphysics in some absolute principle, but that we cannot also embrace the nihilistic relativism of Kant's student, Herder. Ideas from the past can reveal part of who we are, as we realize that we can gain a clearer understanding of our own concepts from the way concepts were articulated in the past. Philosophy has taken a historical turn because there are ancestral concepts that illuminate the roots of current systems.