By Karin A. Nisenbaum
For the Love of Metaphysics: Nihilism and the Conflict of Reason from Kant to Rosenzweig, Oxford University Press, 2018.

My book, For the Love of Metaphysics: Nihilism and the Conflict of Reason from Kant to Rosenzweig (Oxford University Press, 2018), offers a new perspective on the history of German Idealism that focuses on the role of the principle of sufficient reason and the idea of a primacy of practical reason.

In his Critique of Pure Reason, Kant characterizes reason as a faculty that seeks the conditions for whatever is given to it as conditioned, and also the totality of such conditions, which must be unconditioned.Reason seeks an explanation of everything that admits of one, but also a complete explanation in terms of something that does not itself require or admit of an explanation.In my book, I argue that Kant’s view of reason manifests a commitment to a version of the principle of sufficient reason.Yet in the first Critique Kant identifies a clear conflict within speculative or theoretical reason: while we cannot have cognition of unconditioned objects (the objects of primary interest in special metaphysics, such as God, freedom, and the soul), reason through its own internal dynamic demands that we accept the existence of such objects. His Critique of Practical Reason opens the path for a successful resolution of this conflict within the sphere of the practical. While theoretical reason is unable to deliver cognition of anything unconditioned, practical reason justifies belief in precisely those unconditioned objects that are at issue in traditional metaphysics.

In part one of my book, I explain why Jacobi’s and Maimon’s appropriation and transformation of Kant’s Critical philosophy led to a radicalization of the role of practical reason in providing objective reality and cognitive access to the unconditioned, and also to a different diagnosis of the conflict of reason. Employing arguments that have been used in different contexts by the British Idealist Francis Herbert Bradley and more recently by Michael Della Rocca, Peter van Inwagen, and Karl Schaffer, Jacobi claimed that the only way to meet reason’s demand for the unconditioned—for explanations that terminate in something that does not itself require or admit of an explanation—would be to accept a monistic metaphysics; but Jacobi also argued that monism would lead to nihilism and to fatalism. For the post-Kantian German Idealists, solving the conflict of reason and meeting reason’s demand for the unconditioned thus turned into the task of developing a form of monism that wouldn’t result in nihilism or fatalism.  Parts two and three of my book explore the different ways in which Fichte, Schelling, and Rosenzweig attempt to respond to, and overcome, the nihilistic threat that Jacobi first identified, while also accepting Jacobi’s view that only a monistic metaphysics could satisfy reason’s demand for the unconditioned.

Oxford: Oxford University Press, 2018


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“Replies to Critics,” Society for German Idealism and Romanticism Review (2020) (with comments by Lara Ostaric, Omri Boehm, and Naomi Fisher)