In lieu of an abstract, here is a brief excerpt of the content:Reviewed by:Rationalist Empiricism: A Theory of Speculative Critique by Nathan BrownGreg EllermannBrown, Nathan. Rationalist Empiricism: A Theory of Speculative Critique. Fordham University Press, 2021. 318pp.Nathan Brown's Rationalist Empiricism is, above all, a book about philosophical method. It is also a highly significant study of the conceptual architecture of Marxism, developed by way of a critical return to the lesson of Althusser. Drawing on a range of disparate materials–from the (...) works of Descartes, Hume, Hegel, Marx, Heidegger, and Meillassoux to contemporary experiments in digital photography and metrology–Brown demonstrates the necessity of "a mutual interruption of reason and experience" (31) for any theoretical or political practice that would avoid falling into ideological complacency.The book opens with an appraisal of "the speculative turn" (1) in 21st-century thought, a turn Brown characterizes as an intellectual dead-end. He remarks that the various new materialisms and object-oriented ontologies of the last decades were united by an inattention to method. Unconcerned to establish the necessity of their claims or with the relation between reasoning and reality, these philosophies made assertions instead of arguments; they mistook dogmatism for speculation.For Brown, it is the dialectic–specifically, the dialectic of reason and experience–that promises to renew the possibility of speculative thinking. Such renewal will entail refusing "the severance of speculation from critique" (2). It also requires thinking through a more basic problem: the relation between rationalism and empiricism. While rationalism "explore[s] what has to be thought according to the internal order and consistency of ideas," empiricism, as Brown has it, "claim[s] the genesis of ideas in experience" (3). Since Kant's first Critique, this binary and the effort to overcome it have set the terms of philosophical debate. Brown's striking contention is that the search for a synthesis or a hidden ground uniting these two positions (as, for instance, in Deleuze or Michel Henry) invariably leads us back to the transcendental–an improvement on the dogmatism of contemporary theory but a reduction of knowledge to "conditions of experience" [End Page 128] nonetheless (47). Brown therefore proposes another path: "a relational disjunction of rationalism and empiricism" animated by "the critical power of the tension between [them] to check one another's claims and to propel those claims further" (3). In other words, he develops a methodological dialectic whose two poles-the rationalist and the empiricist-alternately take on speculative and critical functions. There is no static alignment of the key categories in Brown's book. "Speculation and critique cannot be parceled out," he writes, "according to the division of reason and experience. Metaphysics, science, politics: each of these fields relies integrally upon the conflict and complementarity of reason and experience, their 'epistemological polarity'" (250). In Bachelard's terms, pivotal for the overall argument, reason and experience must be allowed to "transmute," "propel," and "say 'no' to one another" (8). It is their ungrounded dialectical relation that sustains true speculative thought.This methodological position has profound ontological implications. Looking to Althusser, Brown finds the beginnings of a theory of rationalist empiricism in the structural Marxist notion of the "concrete-in-thought" (15-16): the self-critical and experimentally verified knowledge of a science. Crucially, for Althusser there can be no concrete-in-thought without a "concrete-real," external to theory itself (15). Developing to the fullest this underappreciated point, Brown shows that rationalist empiricism must be a realism. Thus, the book's second, third, and fourth chapters elaborate a continuous argument concerning "the primacy of being over thought" (59), and the relationship between speculative and scientific knowledge. The central question is how speculation might extend or "extrapolate from the exteriorizing force of science, without being reducible to its forms of experience" (261). Refracting Hegel's Logic through the thought of Heidegger and Meillassoux, Brown ultimately offers a new account of the ontological difference–between being and beings, between speculative truth and "ontic," scientific knowledge–that privileges neither side and insists on their coordination. Once again, he declines to seek a synthesis, arguing that "true critique" (as Hegel characterized his speculative method) depends on "the ontological primacy of becoming" (91), on an absolute time bound up with... (shrink)