Routledge Studies in Eighteenth-Century Philosophy
Reviewed by: Alma Buholzer (University College Dublin)
A Guide to Kant’s Psychologism (2019) is presented as a more accessible and to-the-point delivery of the interpretive theses Waxman lays out in Kant’s Model of the Mind (1991), Kant and the Empiricists: Understanding Understanding (2005), and Kant’s Anatomy of the Intelligent Mind (2014). This comparatively compact 351-page book promises a unique angle on Kant’s theoretical philosophy for a range of philosophical and scientific audiences. The work is original both in its iconoclastic style and its thesis, which defends Kant’s ‘psychologism’ and interprets the titular empiricist philosophers as precursors thereof. Kant’s account of objective representation in terms of the interrelations between sensation, pure intuition, logic and concepts is argued to be firmly rooted in problems brought into the spotlight by the empiricists, such as animal consciousness and multimodal sensory perception. The book thus combines a historical sensitivity to the genealogy of Kant’s philosophy with the systematic ambition of a new interpretation, not merely of one isolated aspect of Kantian theory of mind but of the way its various doctrines fit together, from pure intuition to apperception to judgment.
The book is organized into two parts. After an introductory chapter preparing the reader for a radical departure from what Waxman presents as an anti-psychologistic consensus in Kant interpretation, Chapters 2-4 chronologically introduce key thinkers from the empiricist tradition and their contributions to the book’s central concept of psychologism. In chapter 5, Waxman uses Wittgenstein to illustrate Hume’s conventionalism, which in Waxman’s view Kant targets no less than rationalist platonism. Chapters 6-10 guide the reader through Kant’s theoretical philosophy. The sequence of chapters, “The Kantian Cogito” (6), “The Logical I” (7), “The Aesthetic I” (8), “The Objective I” (9), and “The I of Nature” (10) is prescribed less by the text of the Critique of Pure Reason than by the conceptual layers of Waxman’s reconstruction. While regularly referring Kant’s insights back to their empiricist lineage, the progression from the ‘I think’ to the objectivity of physical nature also points to Cartesian and Leibnizian influences in Kant’s treatment of logical universality. The chapters on Kant additionally argue that the doctrines of pure intuition and logical form, interpreted as elements of an ‘a priori psychologism’, can accommodate post-Kantian scientific developments in logic, geometry, mathematics and physics. The concluding chapter assesses platonism and conventionalism as the only possible routes of refutation of Kant’s psychologism, as well as indicating how Waxman’s interpretation may be illuminating for contemporary study of the mind.
One of the most original features of the book is that it makes the compatibility of Kantian doctrines with subsequent scientific advances a matter of first importance: “naturalistic theories like Kant’s and those developed by his British empiricist forebears were intentionally crafted to leave open a place for future science on which philosophy can never impinge” (12). The scope of the book is not only to radically overhaul received opinion on Kant’s methodology, and the relation of his ideas to the sciences, but to defend a biologically plausible version of Kant’s account of logical form. In the remainder of this review I will address in turn: (1) Waxman’s definition of ‘psychologism’ and how his use of this concept situates him with regard to other interpreters; (2) his reading of Kant, with a focus on the logical forms of judgment according to the psychologistic approach; and (3) some questions emerging at the interface of Waxman’s naturalistic reading of Kant and the sciences, especially neuroscience and evolutionary biology.
Waxman stresses that Kant’s ability to resolve skepticism about the objective purport of (some of) our representations is rooted in his radicalization of the British empiricists’ methods to accommodate logical universality, modality, and relational concepts. Thus, the book’s overarching thesis about the relationship between its titular figures is that Kant continues what Locke, Berkeley and Hume started, expressed as their common adherence to psychologism. Waxman has in mind a quite specific interpretation of this term:
[T]he task of psychologism is to explicate meanings, with special emphasis on identifying psychological ingredients essential to notions that, in language, are free of any tincture of psychological content. There can therefore be no expectation that the psychological contents adduced as essential to the meaning of familiar notions will themselves be familiar. (147)
Waxman’s compelling take on the psychologistic philosopher’s undermining of rationalist metaphysics is thus that psychologistic elucidation makes us distrust the appearances of the natural language of metaphysics, thereby overturning realist intuitions that the qualities we discern in appearances are properties of mind-independent objects (33f). Psychologism in this sense, Waxman is clear, is not to be confused with the fallacy of explicating the non-psychological psychologically (305). According to Waxman’s use of the term, psychologism means giving contents which are in fact psychological their due explication in terms of mental representations. Kant’s account of how we are capable of “cognitive representation of sense-divide transcending external objects” (264) equips empirical psychologism with the resources to explicate the objectivity and logical universality of our representations, where this is possible. Hence, “any representational content that neither empirical psychologism nor conventionalism can explicate, a priori psychologism can, and what the latter cannot explicate, nothing can” (147).
Waxman introduces his interpretation as a novel defence of Kant’s theoretical philosophy which rejects two pervasive trends in its reception: an anti-psychologistic consensus, and a more general obsolescence consensus that due to revolutions in logic, geometry, and physics, Kant’s philosophy is “a once formidable structure long since reduced to ruin, fit only for piecemeal salvage” (24ff). The latter engenders attempts to clear the respectable theory behind Kant’s project of its psychologistic methods, resulting in a range of approaches to ‘updating Kant’ e.g. by explaining conscious representation using anything from post-Fregean mathematical logic to Chomskyian linguistics, or Roger Penrose’s quantum theory of consciousness (15). Against these kinds of salvage attempts, Waxman argues that a properly psychologistic account of Kant’s theory of objective representation reveals its compatibility with subsequent developments in logic, geometry, physics, as well as neuroscience and evolutionary biology.
Kant scholars may suspect that the anti-psychologistic consensus is by no means universal: for instance, Andrew Brook’s Kant and the Mind (1994), and Patricia Kitcher’s Kant’s Transcendental Psychology (1990) (see also Falkenstein and Easton 1997) make similar critical points about the anachronism of understanding Kantian theory of cognition ‘anti-psychologistically’. For example, “Kant clearly held that his ‘logic’ of the mind is part of what we would now call psychology” (Brook 1994, 6). Waxman takes note of these authors in a footnote, nonetheless signalling his substantive interpretive differences from Kitcher and Brook as well as Lorne Falkenstein and Scott Edgar. The problem, Waxman explains, is that these authors refer to ‘psychology’, which is concerned with “whether and how a representation comes to be in us (empirically, innately, etc.)” rather than ‘psychologism’, which is concerned with “how the representation itself comes to be” (17n). This distinction, in my view, is not as straightforward as Waxman needs it to be in order to distance himself from other interpreters as far as he claims to.
Waxman himself says in the aforementioned footnote that he agrees with Beatrice Longuenesse’s (1998) work on Kant in its essentials, despite her not using the term psychologism (16). This fosters doubts about exactly what defines Waxman’s psychologism as an interpretive approach. If we stipulate that an anti-psychologistic reading foregoes any reference to mental activity in explicating the meanings of objective representations, psychologistic approaches still come in stronger and weaker flavours, which come down to how the genesis of “the representation itself” is construed.
If ‘psychological’ is interpreted weakly, any view that endorses Kant’s references to mental activities such as synthesis and apperception as non-negotiable parts of the story about objective representation, not wholly translatable into an analytic argument, is “identifying psychological ingredients” (147) in discourse which does not overtly suggest them. I believe most interpreters today would uphold this kind of psychological account. Any particular view on what informs Kant’s psychology need not be empiricist in orientation, as one may instead emphasize the scholastic heritage of Kant’s references to mental acts (e.g. Sellars 1967). On stronger versions, e.g. Kitcher (1990), Kant’s ‘psychologism’ qua account of the genesis of objective representations is a ‘proto-cognitivist’ theory which can be re-formulated in light of contemporary experimental methods and results. Waxman’s qualifies as a weakly psychologistic interpretation, in my view, since nowhere in the book does ‘psychologism’ imply ‘experimental psychology’. In the first chapter and the conclusion, Waxman seems to reject mainly Neo-Kantian attempts to place Kant in the service of twentieth century analytic semantics, philosophy of mind and epistemology—explicitly confronting Strawson (1966) in the conclusion (306), but probably also thinking of authors such as Evans (1982) McDowell (1994), and Cassam (1997). However, they present their work as critical reconstructions and selective adaptations of Kantian ideas. Given that Waxman accuses Strawson’s interpretation of Kant of reverting to a kind of platonism, it would have been interesting to hear more about where Waxman agrees and disagrees with existing criticisms of these Neo-Kantian projects, including McDowell’s (1994) ‘naturalized platonism’.
Let us consider the specifics of Waxman’s use of the term ‘psychologism’. Psychologism is presented as a mode of conceptual explication concerned with the psychological content of the meanings of traditionally metaphysical notions, rather than the psychological mechanisms underlying conceptual meanings. Consciousness turns out to be the key ‘psychological ingredient’ reference to which constitutes a psychologistic account. Waxman stresses that all representation requires some degree of consciousness, but that for Kant and his predecessors consciousness is graded from ‘dark’ to ‘bright’ to ‘clear’ (41) and is hence ubiquitous, reaching down to the sensory representations of basic organisms such as molluscs. Another notable feature of Waxman’s psychologism is its gloss on the normative dimension of Kant’s inquiry into our transcendental justification for applying concepts:
instead of proceeding by defining notions in terms of other notions without regard to whether there is, or even can be, any corresponding conscious representation, psychologism [has] the express aim of seeking out such representations. If the search reveals that a notion owes none of the contents indispensable to its meaning to consciousness, then its scope of application is nowhere limited by it (10).
Conversely, if the notion “can be shown to be beholden to consciousness for any of the ingredients essential to its meaning—ingredients at least implicit, but often explicit, in definitions—then its scope of application is limited accordingly” (10).
In general, the distinctiveness of Waxman’s approach lies in his wholesale engagement with Kant’s more unwieldy terms and concepts, and readiness to endorse Kant’s claims as literally about psychological reality—rather than about concepts, the brain/organism, or the objective world. Despite his psychologistic approach having a foot in psychology and a foot in explication, Waxman is content neither with purely conceptual or exegetical arguments, nor ‘proto-cognitivist’ claims that Kant anticipated cognitive science on this or that front. But he ultimately agrees with many other interpreters that any staunchly ‘anti-psychologistic’ reading is a non-starter, as well as joining Kitcher (1990) and Brook (1994) in thinking that a naturalistic perspective on Kant may be able to contribute to contemporary (experimental) psychology and theory of mind.
I now turn to Waxman’s reading of Kant and his empiricist forerunners. Chapter 2 argues that Locke sets the stage for the psychologistic approach by conceiving consciousness on a scale starting with primitive animals: “Since in the entire absence of sensation no consciousness of any kind seems possible … its terrestrial advent would presumably have coincided with the appearance of the first sensation” (54). In Chapter 3, Berkeley is credited with “extending imagination into the cognitive sphere, thereby for the first time crossing the line separating reality from fiction (where Hume and Kant would follow). This is because the ability to represent space as transcending the divide between sight and touch is indispensable to all cognition of the physical” (85). For Kant, this consideration leads to the thesis that there is nothing in sensation (visual or tactual) that is intrinsically spatial, so the representation of space must be constructed in pure intuition (201). Chapter 4 links the foregoing to Hume’s well-known skeptical challenges to relational concepts:
By shifting the basis of belief in relations from objective experience to subjective feeling, Hume moved the topic from epistemology to psychology where, instead of needing to be justified by evidence and to follow as a conclusion from premises, belief is determined purely affectively, by association-constituting feeling, and nothing else (96).
For Waxman, Hume was the first to psychologistically attribute fully general concepts such as the uniformity of nature and the general causal maxim to humans and non-human animals alike (114). Waxman illustrates the theoretical development from associationism to Kantian a priori psychologism in terms of a speculative evolutionary development from a creature
capable of the kind of highly sophisticated, behaviourally efficacious conscious mentation that Berkeley and Hume devised their associationist psychology to explain. Thanks to some fortuitous mutation or other alteration in its genome, its progeny included creatures capable of the representation ‘I think.’ Having no evident selective advantage by itself, this neural capacity presumably could have established itself in the population only as a spandrel piggy-backing on some genetically connected trait that earned its evolutionary keep. (177)
Eventually enabling complex propositions and inferences, Waxman contends, the ‘I-think’ representation would have enabled behaviours with adaptive value. This evolutionary story complements Waxman’s interpretation of Kant’s logical forms of judgment as more basic than language and indeed making language possible:
The ability of linguistic propositions to blend with non-linguistic is, in its way, no less amazing than the mathematizability of nature. But isn’t this exactly what we should expect if language was originally crafted by creatures already fully conversant in the use of non-linguistic propositional representation, transcendental judgments included? (315).
The chapters of Part II centre around Kant’s psychologization of logic in relation to sensory and propositional representation. Waxman details how Kant adapts from Descartes the contentless representation ‘I think’, which “in and of itself, has no content [and hence] cannot be suspected of having borrowed any, whether from language or anywhere else” (158). Being non-linguistic, it is not attributable to convention and thus provides a purely psychological basis for logical generality that synthetically unifies all possible representable contents (174). According to this notion of pure apperception, Waxman argues that Kantian logic is based in a universal self-consciousness which includes “the totality of logical structures universals enable us to form—propositions, inferences, narratives, et al.” (149). Unfortunately, Waxman doesn’t elaborate on whether self-consciousness is for Kant always a form of ‘bright consciousness’, or could exist in ‘darker’ shades as he argues it does for Hume (120).
Kant brings what Waxman calls “intelligence”—which amounts to consciousness of universality and modality—to Humean representations of general relational concepts which lack any awareness of the “logical universe of possible representations” (171). Kantian concepts “enable us to consciously represent each and every associative combination as a grouping of denizens of the logical universe that are thereafter sortable not only by their sensible/imaginable properties but by their logical ones as well” (171). According to Waxman, Kant’s logical forms of judgment are what “make any ‘I think’-generated concept combinable with any other such concept in a single act of thought, or propositional representation” (167). Conceptual representation is thus explicated as the gradual elimination of degrees of “logical freedom” (150) by restricting the space of logical possibilities to what is representable given the content supplied by sensation and association.
According to Kant’s psychologization of logic, fixing the position of a term as subject or as predicate in a categorical judgment is a psychological act starting with the bifurcation of the logical universe (170). However, such a “logical form by itself cannot guarantee that a proposition will result. In particular, even if a would-be proposition is logically well formed, it would still fail to be a genuine proposition if, for other than strictly formal logical reasons, it cannot be thought without generating not just falsehood but one or another species of impossibility, e.g. … ‘water is not always H2O’” (175). For Waxman’s Kant, categorical form permits the unification of concepts in a single consciousness, but it does not allow a unified representation of the resulting propositions (175). In addition to the assertoric modality, then, we need Kant’s problematic modality, which asserts merely the relation between two propositions, suspending judgment on the propositions themselves. The logical form this assumes in us, hypothetical judgment, relates problematic propositions as ground to consequent in the assertoric modality. Together, hypothetical and categorical forms enable any combination of the totality of possible propositions to be unified in a single conscious act (175f).
Waxman mobilizes this account to show that Kant (1) does not restrict intelligence to language-using organisms, nor (2) does he impose our parochial linguistic structures on his model of the basic “building blocks of propositional thought” (22). Waxman takes his elucidation of Kant’s transcendental logic to counter both misconceptions:
Intelligence can be accorded to any creature, actual or possible, that is capable of pure apperception … even including beings so asocial as to be devoid of anything remotely analogous to language or socially grounded symbolic communication of any kind. This is not to deny that Kant regarded all non-human animals known to him as incapable of apperception and therefore unintelligent. (172)
But, Waxman adds, “that does not mean he would have persisted in that view had he known what we know today” (172). This is an interesting speculation, implying that animals have some form of awareness of universality and modality—not in Hume’s sense, but in Waxman’s more demanding Kantian sense of apperception—“an a priori logical universe that quite literally encompasses all possible conscious representations” (169). I fully agree that Kant’s logic is non-linguistic, but I want to know more exactly how Waxman understands our present knowledge of animal intelligence such that it could make Kant change his mind on this controversial topic.
Waxman regularly refers to his lengthier engagements with Kant’s first Critique in footnotes. These references will be necessary for scholars seeking to determine Waxman’s position on exegetical debates. Part II succeeds in presenting Kant’s account of logical forms and concepts as centrally relying on consciousness, and hence psychologistic, while emphasizing that propositional representation need not be construed as an evolutionary leap separating humans from other animals. The combination of these theses makes for an original, stimulating addition to works on Kant’s first Critique.
I now have some remarks on the book’s intriguing but somewhat ambivalent references to the sciences. Waxman’s general stance that the insights of Kantian psychologism extend beyond their own scientific and philosophical context is very ambitious, and I’m not sure his case is equally strong for each of the sciences he addresses. Waxman makes a convincing case that non-Euclidean geometries cannot falsify any of Kant’s statements about pure intuition, as the latter pertain to the necessary features of any representation of space, rather than any particular geometry:
the formal intuition of space is not only neither Euclidean nor non-Euclidean but completely indeterminate as regards number, limit, distance, metric, part-whole relationships, and everything else that makes space suitable for properly mathematical representation or objective representation of any kind (208-9).
When it comes to the life sciences, however, Waxman’s perspective is (perhaps inevitably) more in tension with the scientific context Kant was writing in.
Waxman is clearly not neutral on matters of philosophy of consciousness, stating at the outset that consciousness is for his purposes identical in existence to its neural correlates (13-14), but that there is nonetheless a distinct psychological reality (14, 57, 159, 162, 177f). As this commitment is not compared to any alternatives, I am curious as to why he has opted for this particular form of identity theory to defend the biological plausibility of Kant’s psychologism, rather than functionalism or some form of emergentism. Polák and Marvan (2018), for example, defend the view preferred by Waxman that neural correlates are not in a causal relation to conscious states but an identity relation—a position which philosophers of mind might like to see defended more explicitly in connection with Kant’s views. Also, they may ask whether there is a specifically Kantian motivation for understanding the “mystery of consciousness” as Waxman does, that is, “a purely physical existence that is at the same time irreducible to physical reality” (14). Waxman clearly wants a naturalistic position to complement his psychologistic interpretation, but he also does not want to impose too much recent theory on the historical theories. Given this concern, psychophysical parallelism—an early form of identity theory espoused in different (including Neo-Kantian) versions by German philosophers from Fechner to Feigl via Riehl and Schlick—could illuminate Kantian psychologism from this side of Darwin and experimental psychology (see Heidelberger 2004, Ch. 5). Of course, it would be possible for most Kant scholars to profess neutrality with respect to these debates, but Waxman has—to his credit—set different standards.
Waxman’s decision to adhere to Kant’s original terminology and to steer clear of issues of translation in one sense makes the book smoother. The book conveniently contains a glossary, and tailor-made terms such as ‘AUA [analytic unity of apperception] concepts’, and ‘dark consciousness’ helpfully remind us that a term is not being used in its familiar sense. Waxman’s capacious use of ‘consciousness’ clearly works in his favour insofar as Modern and Kantian philosophy become much more relatable simply by lowering the threshold (as we understand it) on what sensory and cognitive states count as conscious. Yet it would have helped for Waxman to illustrate the general features of (what Descartes, Locke and Kant viewed as) ‘dark consciousness’ in more descriptive neural or psychophysical terms—not simply because readers may have difficulty forgetting the current meanings of such terms and the controversies attached to them, but because it would improve the book’s case for making psychologism compatible with contemporary biology.
One of the book’s most interesting features is its rapprochement between Kant and Darwin. Frequent references to phylogeny and the evolutionary plausibility of psychologism (as contrasted with platonism and conventionalism) evidence Waxman’s eagerness to integrate Kant’s insights into a post-Darwinian landscape, which I take to be a very important, relatively neglected project:
[N]ot only is Kant’s psychologism consistent with evolution, it actually spotlights suitably primitive forms of empirical consciousness that would gain adaptational advantages from a priori consciousness. Most basically, formal intuitions can easily be conceived to be of use to minds grappling with the challenge of combining external sensations into a single, unified external sense capable of providing immediate access to sense-divide transcending objects. (306)
This illumination does not go both ways, however, since Waxman also says that transcendental consciousness is entirely outside the scope of scientific explanation (295)—“because the subjectivity constituted by apperception … becomes part of the explanation of the physical, it cannot itself be explained physically on pain of circularity” (23). This claim recalls circularity charges against naturalized epistemology and logic, which in my view can be convincingly refuted by pragmatic and holistic considerations. It also blatantly contradicts the book’s initial claim that “[t]he mental is causally and in every other way fully determined by its physical underpinnings, and so is in principle fully explicable by science” (21). This is surprising, after seeing Waxman go to great lengths to argue that although a priori, the most innovative aspects of Kantian philosophy are features of our natural constitution, different in complexity but not radically different in kind from the sensory sensitivity of an oyster. Placing a priori elements of Kantian psychologism beyond the reach of current and future biological explanation strikes me as a missed opportunity, and again makes me doubt what is meant by psychologism. Empirical research in animals can indicate how consciousness might have arisen, and in a footnote Waxman considers but then discards a few such accounts based on their comparatively restrictive definition of consciousness (63n). The reader may suspect that casting the net more widely would reveal theories more congenial to Waxman’s evolutionary take on subjectivity, such as Godfrey-Smith (2016).
The following passage is a good example of Waxman’s ambivalence towards his own naturalistic outlook:
The connection between the subjective psychological reality of consciousness and the objective physical reality of neurophysiology is a complete mystery in both directions, today and quite possibly for some time to come. Thus, Kantian logical forms of judgment pose no special mystery but instead are best regarded as simply an additional species of phylogeny-dependent neuro-psychological reality in addition to sensations, emotions, dreams, and the rest. (178)
Because Waxman has not restricted himself to purely exegetical argument, or the Kitcherian ‘proto-cognitivist’ angle described earlier, the reader may wonder how literally such claims are to be taken. One cannot but agree that (something similar to) Kantian a priori capacities such as the logical forms of judgment must have evolved somehow, just as there must be some neural correlates for the empiricists’ associative psychologies, as indicated in Part I. But the empirically-minded reader will want to know in more detail how forms of judgment (or their successors in contemporary science of mind) could be modelled and studied, if they are on a par with sensations and emotions.
A Guide to Kant’s Psychologism is bound to appeal to diverse philosophical audiences for its fresh take on Kant’s theoretical philosophy as a priori psychologism. It is also a lively, articulate instance of philosophical storytelling. Waxman avoids approaching Kant through the lens of contemporary philosophical problems where semantics, epistemology and metaphysics are concerned. When it comes to the sciences, however, the book makes us acutely aware of pieces of the puzzle of the mind in nature that Kant simply cannot have anticipated. Kant’s understanding of his current science needs to be confronted with today’s sciences in order to address all of the questions raised by an interpretation of Kantian philosophy as naturalistic a priori psychologism. Over the course of Waxman’s book, frequent references to neural correlates and phylogeny habituate the reader to seeing our biological reality in the same conceptual space as Kantian doctrines, which is surely a step in the right direction. As is perhaps Waxman’s intention, it is left to the reader to ponder the convergences and divergences between Kant’s account of the mind and current scientific knowledge, perhaps especially the life sciences. The book offers its non-Kantian readers a challenging, raw encounter with Kant’s theoretical philosophy, and will leave Kant scholars much to think about both on the old problem of psychologism and new ones arising from Waxman’s brand of naturalism.
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