Affectivity and Philosophy after Spinoza and Nietzsche: Making Knowledge the Most Powerful Affect by Stuart Pethick (review)

In 1881 Nietzsche discovered that he had a precursor: Spinoza. In a letter to Franz Overbeck postmarked July 30—the eve of the experience of the eternal recurrence—he enumerated the points of doctrine that he believed he shared with Spinoza, including the denial of free will, a moral world order, and evil, and he also mentioned the task of "making knowledge the most powerful affect [die Erkenntniß zum mächtigsten Affekt zu machen]" (KSB 6:111). A note of the same year reads, "Spinoza: We are only determined in our actions by desires and affects. Knowledge must be an affect in order to be a motive. I say: it must be a passion to be a motive" (KSA 9:11[193]). Nietzsche's first published reference to the "passion of knowledge [Leidenschaft der Erkenntnis]" is also from this year: he remarks in D 429 that the drive to knowledge has become so strongly rooted in us that we could not now sacrifice knowledge for happiness. Indeed, he suggests that such is our passion for knowledge that even the prospect of humanity perishing of it does not exert any real influence on us.

So, what exactly does it mean to "make knowledge the most powerful affect" and to have "the passion of knowledge"? In his instructive study, Stuart Pethick proposes to bring Spinoza and Nietzsche into rapport on the affective character of the practice of knowledge. According to him, both philosophers are committed to orienting thought around "the immanence of affectivity" (198). Pethick contends that this is not a matter of creating a philosophy "of " affectivity, simply because for both Nietzsche and Spinoza knowledge is not, and cannot be, an end in itself or the purpose of philosophy: "Affectivity is not an object of study in any straightforward sense; affectivity can be named and described in different terms, but doing this is a way of altering the manner in which we affect and are affected, and not a way of learning how to control or avoid affectivity from an insulated and unaffected viewpoint" (198). This insight is what, for Pethick, making knowledge the most powerful affect rests on. It requires that we conceive of philosophy not as "a normative practice that searches for happiness through the knowledge of what 'is'" (199), but as a creative enterprise—as, for example, the creation of fluid concepts—that intensifies the joy we take in transient experience. An epistemological revolution of sorts is thus effected by Spinoza and Nietzsche, one that makes knowledge no longer a matter of simply ascertaining what things are in terms of their "whatness," but rather an exploration of how things—including bodies, ideas, and values—come about and how they affect and are affected.

In his opening chapter, Pethick is insightful in endeavoring to wrest Spinoza from totalizing ontological readings; in Pethick's estimation, he is as much a perspectivist as Nietzsche. Pethick is also instructive when he proposes to read Spinoza not simply as the arch-rationalist he is often taken to be, but as a philosopher of the body whose focus is on the becoming of bodies in terms of their dynamic and affective relations (and there is no thinking without a body). Here he is following the lead of Gilles Deleuze, in whose classic text of 1968, Expressionism in Philosophy: Spinoza, Spinoza is as much an experimental empiricist as a rationalist.

Chapters 2 and 3 are devoted to Nietzsche, and the fourth and final chapter—perhaps the strongest and most innovative in the book—provides an account of the compatible conceptions of philosophy we find in Spinoza and Nietzsche, centered on their affective conceptions of knowledge. Overall, Pethick shows himself to be an adept and diligent reader of Nietzsche, and he has fresh and novel insights to offer into the core doctrines of eternal recurrence, amor fati, and the will to power. Let...