What are we to make of this assertion? Does not Merleau-Ponty fall into the trap of the same intellectualist philosophies he denounces in these lines? But we must first agree on what that “disavowal” means. Merleau-Ponty explains himself on that count with reference to Husserl’s own approach: It is not that phenomenology should be “indifferent” to the empirical sciences and psychology (PrP, 21/77) but that it must avoid modeling itself on their method. “It is a matter of renewing psychology on its own terrain, of bringing to life the methods proper to it by analyses which fix the persistently uncertain meaning of fundamental essences, such as ‘representation,’ ‘memory,’ etc.” (PrP, 22–23/78). When Husserl—and Merleau-Ponty as well—criticizes psychology, he hardly does so to call into question the legitimacy of an inductive approach; rather, he seeks to shore it up with an eidetic approach. There is unquestionably a continuity between The Structure of Behavior, the first book that emerged from Merleau-Ponty’s reflections in contact with the sciences, and Phenomenology of Perception (1945). In the earlier work, published in 1942 but already completed in 1938, he attempts to conceive of perception with and against science; in the second, he radicalizes that movement while making an effort to identify what science assumes and what, qua assumption, remains its unthought—the lived experience of the sensible world. In the preface, he maintains that “if we wish to think science rigorously, to appreciate precisely its sense and its scope, we must first awaken that experience of the world of which science is the second-order expression” (PP, iii/lxxii).

Before we arrive at the question of primordial expression—the subject of my next chapter—let me insist once again on the unitary aim of that entire first phase but also on the differences at work. Whereas The Structure of Behavior takes a negative path, insisting on why a phenomenological approach cannot be reduced to behavioral psychology, Phenomenology of Perception seeks to elaborate a positive account of the life of the embodied subject. The first book seeks, according to the explanation that Merleau-Ponty himself gives, to determine the sense (or nonsense) of an approach that considers the human being “from the point of view of the disinterested onlooker” (P2, 12), whereas the second, “placing itself within the subject” (P2, 13), brings to light the unthought, that is, experience, on the basis of experience itself. When we consider these two works side by side, we discover a chiasm: Where Phenomenology of Perception belongs fundamentally to a mode of thinking from inside experience and places positive knowledge in a position of exteriority, The Structure of Behavior does not yet situate itself within an experiential perspective but rather argues from within scientific discourse, producing a critique of the sciences that is paradoxically informed by these same disciplines.⁴

That interpretation may grant too much weight to Merleau-Ponty’s later efforts in 1951 to reconcile the arguments in his previous books in support of his pending candidacy for a position at the Collège de France (one cannot fail to observe the conceptual evolution that occurred between The Structure of Behavior and Phenomenology of Perception). In its intentions, however, the earlier book already brings about a radical displacement of the philosophical milieu within which Merleau-Ponty sought to speak. As a result, it reactivates the problem of the relation between body and soul—since, of course, it is this old problem that is, once again, at stake. And it does so without trudging through the aporias of the tradition. Rather, it installs itself from the start within scientific debate, which carefully avoids these metaphysical dichotomies. It raises once again the question of the relation between activity and passivity, not reducing them to the subject-object duality but analyzing what precedes that distinction, namely, behavior. In that sense, behavior is less the book’s theme—which is already and still perception—than its strategic apparatus. In opting for the scientific domain, then, Merleau-Ponty already distinguishes his thought from an intellectualist philosophy that dissolves perception into “thinking about perception.” In taking behavior as a shortcut across the field of the empirical sciences, he already chooses a path that will allow him to arrive at his object, experience proper.⁵ For the moment, however, let us remain within the layout of The Structure of Behavior. In it Merleau-Ponty studies very heterogeneous concepts one by one, still struggling to identify his own point of view, which has led a number of commentators to set aside that first book in favor of the second. I believe, however, that by 1933–38, when he was working on The Structure of Behavior, the critical perspective that would persist throughout all the different inquiries to which Merleau-Ponty subsequently dedicated himself was already taking shape: namely, a philosophy that denounces any philosophy of transparency. Although the term “transparency” does not yet have the value of an operative concept that it will later assume,⁶ the motif is already undeniably present. In addition, the opacification of perception and its reinsertion into the life of the embodied subject, which will lead to Phenomenology of Perception, is no doubt the unifying moment of the disparate analyses of the earlier book.

In The Structure of Behavior, Merleau-Ponty also discusses the philosophical positions that reject such a materialist atomism. He shows that, ultimately, they too still operate within the very system they reject. On the one hand, vitalism claims to reintroduce vital force where there is only mechanical force. Although that vital force evades the classic physicalist explanation, its effects must be reintegrated into the mechanical and turn out to be only a supplementary factor (SC, 149/138). As a result, vitalism paradoxically takes the forms of a “physics in the living being,” without really managing to conceptualize the “physics of the living being” (SC, 164/151). On the other hand, intellectualism moves beyond the juxtapositions of atomism, but only to displace the sensible to the sphere of understanding. Given the heterogeneity of essence between the sensible and the perceived, there would no longer be a relation of contiguity but rather a relation of conformity. Neo-Kantian thought—strongly rooted in interwar France and Merleau-Ponty’s target whenever he uses the term criticisme—would simply reduce perception to one mode of judgment among others (SC, 217/201). That prevents it from putting “consciousness in contact with an opaque and foreign reality” (SC, 283/224). In contrast to mechanistic philosophy, which understands behavior in terms of an initial state of transparency—and whose approach is not truly called into question by vitalism but rather confirmed by it—and in contrast to intellectualism, which reduces behavior to the instrument of an ideality, the key issue for Merleau-Ponty is to conceptualize the organization of the sensible in terms of perception. Contrary to any reductive doctrine, which, in the case of intellectualism, gives rise to a transparent model of thought and, in the case of mechanism, to a “mosaic” of sensations (here Merleau-Ponty is using Max Wertheimer’s expression), he believes one must consider “the total ‘image’ of the organism” (SC, 22/23). He finds the principle for that comprehensive approach in Gestalt psychology, to which he will ceaselessly return until the last of his writings. Whereas materialist atomism claims to provide explanations on the basis of a fragmentation of the causal chains, the Gestalt school’s credo is that the whole is always greater than the sum of its parts (SC, 49/47). Even if there truly is a distinction of the parts within the whole, these parts cannot be separated out, because they constitute an organic totality. Form (Gestalt) is neither in things nor in consciousness: It organizes their relation. Above all, it is structure.

Much later, at a conference on the word “structure” held in Paris in January 1959, Merleau-Ponty will provide a definition of that term that applies equally well to “form”: Structure is an “internal principle of an observable distribution” (S, 154).⁷ The emphasis is on “observable,” since, contrary to the more common usage of the term by what is usually classified as “structuralism,” this is not a structure underlying the world of the senses but a structure within the world of the senses. As such, it is constitutively sensible. Even though, by virtue of the terms “form” and “structure” (often used interchangeably in The Structure of Behavior), a number of inherited forms of reductionism are swept aside, other difficulties persist. For Merleau-Ponty, the school of Kurt Koffka and Wolfgang Köhler tends to substantiali...