The answer to these questions, pursued and modeled in the following chapters, lies in a reengagement of the opposition between rationalism and empiricism—an effort to rethink the apparent contradiction between the priority of reason and the priority of experience without appeal to the priority of the transcendental, and thus in a manner shorn of transcendental guarantee.3 If we criticize the delimitation of knowledge to the field of possible experience—as we must—we thereby reopen the transcendentally displaced question of how the methodological relationship of rationalism and empiricism is to be theorized and practiced. If the transcendental does not suffice to ground the displacement of their opposition, because the subject of transcendental conditions is ungrounded, how can the claims of rationalism and empiricism be brought into a mutually reinforcing dialectic that does not accept or rely upon the priority of either method? I pose this question as the problem of the relationship between speculation and critique.
What I call rationalist empiricism involves the delimitation of transcendental philosophy through speculative critique. The methodological trajectory thus designated does not accept the severance of speculation from critique, nor critique from speculation. Rather, it aims to marshal the critical power of the tension between rationalism and empiricism to check one another’s claims and to propel those claims further. In order for this movement of critical delimitation and speculative extension to function, rationalism and empiricism can neither be collapsed into one another, nor defended as methodologically autonomous from or superior to the other’s claims. Nor can the tension of their opposition be displaced by appeal to transcendental grounds. Philosophy must sustain a relational disjunction of rationalism and empiricism in order to sustain the power of speculative critique.
By “rationalist” I mean to denote a philosophical orientation deploying the power of reason to push thought beyond the limits of experience, to explore what has to be thought according to the internal order and consistency of ideas. By empiricism I refer to a philosophical orientation claiming the genesis of ideas in experience and grounding the determination of what is the case on the consistency of thinking with experiential fact. But what are the limits of “experiential fact?” Is what happens in thought itself a form of experience? Does the exploration of the order and consistency of ideas itself yield experiential facts? Are there forms of experience that cannot be subordinated to knowledge gleaned from experience? What is at issue in such questions is how one determines criteria of the a priori and the a posteriori, and how exactly one conceives the relation of rationalism and empiricism to these categories. Rationalist empiricism denotes, one the one hand, a methodological attunement toward the experience of thinking as included in the field of what happens and, on the other hand, an attunement to the power of thought to push the field of facts beyond the presumed synthesis of the past with the future, referring what happens to what has to be thought, rather than to the succession of experience. I refer to “rationalist empiricism” rather than “empiricist rationalism” because it is the advent of reason, intervening in experience, that inaugurates philosophical speculation and that requires critique. Rational speculation cannot be grounded by or limited to experience, but it involves a commitment to empiricism insofar as it cannot violate the critical force of scientific knowledge. A rationalist orientation toward empiricism pushes beyond the limits of experience through the order and connection of ideas, but such an orientation can neither ground nor invalidate the criteria of experience within limits. The delicate task of rationalist empiricism is thus to preserve the distinction and autonomy of its methodological poles while also submitting each to the critical interrogation of the other, acknowledging and accounting for the discrepancy of their criteria.
This book limns a recessed history of rationalist empiricism in order to demonstrate the importance of this history to the methodological problems of contemporary philosophy. Through an engagement with these contemporary methodological problems, Rationalist Empiricism returns to the tradition from a perspective indifferent to the positioning of speculation against critique, or critique against speculation. What has been missed in debates concerning “the speculative turn,” I would argue, is a certain methodological complexity that often also goes overlooked in the work of Plato, Descartes, Hume, Hegel, or Marx: the refraction of rationalism and empiricism through one another’s criteria—sometimes in the form of methodological exceptions, sometimes in the systematic resonance of a concept absent from a system, sometimes through dialectical movement, sometimes through a non-dialectical encounter between thought and event. The methodological consequences of such refraction have to be reconstructed, have to be read back into the tradition from which they emerge, and my view is that certain texts of recent and contemporary French philosophy suggest the necessity of such reconstruction and offer a guide to its means.
One of these is Quentin Meillassoux’s After Finitude: An Essay on the Necessity of Contingency. The reception of Meillassoux’s slender tract has focused primarily upon its polemics, its examples, its concepts, and its proofs: the critique of correlationism, the figure of the arche-fossil, the concept of “hyper-chaos,” the proof of the necessity of contingency. What I find striking about the book is its method. By this I do not mean, as has often been emphasized, its style—the clarity of its argumentation and the classical tension between rhetorical concision and explosive conceptual development that it deploys. I mean that Meillassoux is both a rationalist and an empiricist, both a Cartesian and a Humean, and that he shows, perhaps for the first time, precisely how the philosophical itineraries of Descartes and Hume are not only compatible but carry one another toward singular ontological and epistemological consequences when reconstructed from a particular point of view. Obsessed with the relation between Descartes’s Meditations and Hume’s Enquiry as a student—with the theory of primary and secondary qualities, and with the problem of induction—I later recognized in Meillassoux’s book an engagement with questions I had often reflected on, though never formulated with such precision: If the articulation of Hume’s problem is not a specimen of philosophical skepticism, but rather a disavowed token of rationalist confidence, how does it comport with Descartes’s understanding of the distinction between the fragile evidence of sensory phenomena and the formal construction of primary qualities? What bearing does Descartes’s mathematical rationalism have upon the problem of causality articulated by Hume? And if we find Kant’s solution to such questions (transcendental critique) unsatisfactory, while also finding ourselves unable to settle into speculative assertions that would merely posit the absolute, how can we carry forward the strange and unresolved consequences of Hume’s argument while still holding onto the prospect of what Descartes theorized as knowledge of primary qualities, or what Spinoza would call “adequate ideas?” I could not have articulated these questions in this form before reading Meillassoux’s work, but they had nevertheless pressed upon me since I began to study philosophy. That is why I gravitated toward the issues at stake in After Finitude, despite what also struck me as an increasingly superficial reception of the book, foregrounding slogans and anti-critical polemics rather than more subtle dimensions of the methodologically complex way its arguments were made.
For me the real consequences of Meillassoux’s book lay in its repositioning of the apparent opposition between rationalism and empiricism, which Kant’s transcendental critique had not quite foreclosed. This repositioning revived not only the speculative vocation of philosophy but also the problem of the relationship between speculation and critique. This latter problem was made all the more pressing by the fact that, unlike some of his contemporaries, Meillassoux proceeded with deep respect for the philosophical questions opened, rather than obviated, by Kantian critique. Meillassoux affirmed that the question posed by “the problem of ancestrality”—“what is the condition that legitimates science’s ancestral statements?”—“seems to be a question of the transcendental type,” but he recognized its peculiarity, “in that its primary condition is the relinquishing of transcendentalism.” He criticized the reduction of knowledge to a subjective correlate imposed by “correlationism,” yet he demanded that “we remain as distant from naïve realism as