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Articulating the WorldConceptual Understanding and the Scientific Image$

Joseph Rouse

Print publication date: 2015

Print ISBN-13: 9780226293677

Published to Chicago Scholarship Online: May 2016

DOI: 10.7208/chicago/9780226293707.001.0001

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Naturalism and the Scientific Image

Naturalism and the Scientific Image

(p.3) One Naturalism and the Scientific Image
Articulating the World

Joseph Rouse

University of Chicago Press

Abstract and Keywords

Naturalists have at least three core commitments: refusing appeals to what is supernatural or transcendent to nature; making scientific understanding central to philosophical understanding; and repudiating any “first philosophy” as authoritative over the sciences. This introductory chapter emphasizes that naturalism is a historically developing project, as new scientific work and philosophical criticisms of earlier versions of naturalism revise our understanding of these naturalistic commitments, and how they can be upheld. Naturalism nowadays is more influentially shaped by Sellars’s aspiration to fuse the scientific and manifest images than by Quine’s version of naturalism. This chapter explains how the prospects for a defensible naturalism have been advanced by three important, mutually supportive developments: John Haugeland’s, Robert Brandom’s and John McDowell’s refinements of the manifest image; philosophical and interdisciplinary studies of scientific practice; and recent developments in evolutionary biology that extend and revise the neo-Darwinian “modern synthesis”, especially niche construction. The chapter concludes by previewing the book’s revised account of conceptual understanding and scientific practice, and how it more adequately satisfies naturalists’ core commitments.

Keywords:   naturalism, scientific understanding, Sellars, scientific image, manifest image, John Haugeland, Robert Brandom, John McDowell, scientific practice, evolutionary synthesis

I—Naturalism as a Historical Project

This book aims to advance a naturalistic self-understanding. Naturalism conjoins several core commitments. First, its advocates refuse any appeal to or acceptance of what is supernatural or otherwise transcendent to the natural world. The relevant boundary between nature and what would be supernatural or otherwise transcendent is admittedly contested, and conceptions of that boundary have shifted historically. The significance of conflicts over what is or is not “natural” nevertheless arises in substantial part from the aspiration to a naturalistic understanding. Conceptions of nature and aspirations to a naturalistic self-understanding may be mutually intertwined. Contemporary naturalists also undertake a second more specific commitment to a scientific understanding of nature. At a minimum, naturalists regard scientific understanding as relevant to all significant aspects of human life and only countenance ways of thinking and forms of life that are consistent with that understanding. More stringent versions of naturalism take scientific understanding to be sufficient for our intellectual and theoretical projects and perhaps even for practical guidance in other aspects of life. A third commitment is a corollary to recognition of the relevance and authority of scientific understanding: naturalists repudiate any conception of “first philosophy” as prior to or authoritative over scientific understanding (Quine 1981, 67).

(p.4) The book develops these core commitments in ways that many fellow naturalists will find unfamiliar and perhaps even alien. I therefore need to be clear from the outset about why I still identify these proposals as a naturalistic program. Naturalism has a long and distinguished history that predates its contemporary versions. That history encompasses the earliest human efforts to understand the world and our place within it without invoking gods, mysteries, or other incomprehensible or otherworldly beings, powers, or authority. The emergence and expansion of the modern natural sciences encouraged the identification of naturalism with a commitment to the autonomy and authority of scientific understanding. Yet the constructive development of a naturalistic self-understanding extends beyond the efforts of those thinkers and inquirers who explicitly embraced a naturalistic project. Adamant critics of naturalism have developed or advanced many important aspects of what we can now recognize as a naturalistic self-understanding. Scientific achievements guided by theologically framed natural philosophies were prominent among those contributions, but philosophical objections to a naturalistic standpoint have also led to improvements in its prospects.

In retrospect, there should be no irony in the recognition that ardent critics of naturalism have constructively advanced the cause. Articulating a thoroughly naturalistic self-understanding is difficult. Throughout the history of naturalistic thought, and in some respects even today, committing to a naturalistic self-understanding required some philosophical myopia. Apart from having to cope with significant gaps in understanding the natural world, naturalists have often embraced what look in retrospect to be oversimplified conceptions of what a defensible naturalism would require. Some proponents were overly optimistic about the capacities of austere scientific and philosophical resources. Others overlooked residual theological or supernatural commitments in their own efforts. Many have not fully recognized or understood the complexity of the phenomena a naturalist must account for or the sources of incoherence within their projects. How else could they endorse and defend commitments that would otherwise outrun the limits of recognizable feasibility? It should be no surprise that the challenges confronting a more adequate philosophical naturalism have often been most carefully and insightfully understood by those who therefore eschewed any commitment to naturalism. As Charles Taylor noted, “In philosophy at least, a gain in clarity is worth a thinning of the ranks” (1985, 21).

(p.5) Recognizing the dialectical complexity of philosophical naturalism throughout its history has important consequences. Naturalism as a philosophical and scientific project cannot simply be identified with any of its various formulations, including currently prominent versions. Some of the most important achievements within the naturalistic tradition have reformulated which commitments a genuinely naturalistic project must undertake. Many of these reformulations had philosophical roots. Hume’s criticisms of causal necessity and of derivations of “ought” from “is,” Kant’s “Copernican Revolution,” Frege’s and Husserl’s arguments against psychologism, Quine’s riticism of the analytic/synthetic distinction, and Wittgenstein’s reflections on rule following, among others, have left their mark upon subsequent formulations of naturalism.1

Other revisions in then-predominant conceptions of naturalism call attention to implicit tensions between naturalistic philosophy and the empirical sciences. The establishment and pursuit of new scientific inquiries have been crucial to the advance of naturalism. Indeed, naturalism is nowadays often simply identified with a scientific or even scientistic conception of the world. Yet the potential tensions between philosophical naturalism and the empirical sciences are apparent from the many occasions when scientific developments have stranded scientifically based philosophical programs. Philosophical naturalisms have often confronted disciplinary, theoretical, methodological, or empirical innovations and discoveries in the sciences that challenged their version of naturalistic understanding. Examples of broadly naturalistic scruples undermined by scientific developments include seventeenth-century mechanistic hostility to “occult” gravitational action-at-a-distance, causal determinisms grounded in classical physics, Quine’s commitment to behaviorism, or the rejection of biological teleology. Moreover, the proliferation of relatively autonomous scientific disciplines and research programs leaves open the question of which approaches to which sciences would most constructively advance a naturalistic point of view. Fundamental physics, evolutionary biology, neuroscience, cognitive psychology, and the sociology of knowledge are prominent among contemporary (p.6) contenders, but the relations among these scientific orientations and their respective philosophical significance for naturalists remain contested.

I regard naturalism as a historically situated philosophical project.2 We find ourselves in the midst of ongoing conflicts over what naturalism’s commitments are and why they matter, along with challenges to those commitments. I do not here defend a naturalistic self-understanding against those who regard it as unattractive. I endorse a broadly naturalistic stance, but my reasons for doing so are familiar, and I have nothing especially original to say on that topic. I am instead concerned to respond to the possibility that a consistent and thoroughgoing naturalistic self-understanding is unattainable. This book proposes revised conceptions of ourselves and of the sciences that are directly responsive to conflicts over the viability of a naturalistic stance. It reformulates the dominant contemporary philosophical conceptions of naturalism, both by reworking received philosophical approaches to science, intentionality, and conceptual understanding and by drawing upon recent scientific work that has mostly not yet been assimilated philosophically. I endorse the resulting conception, but I do not propose that it would or should settle these issues once and for all. The questions of what philosophical naturalism is, what must be done to sustain a viable naturalistic orientation, and whether and why to be a naturalist will undoubtedly remain at issue within the tradition. My aim is instead to refine and clarify these issues to avoid recognized or recognizable problems and to propose and defend new directions for further philosophical and scientific work in response. These limited aspirations do not merely result from modesty about what I did or could accomplish, though modesty is undoubtedly appropriate. These aspirations are instead shaped by the conceptions of science and philosophy developed in the course of the book, which emphasize that conceptual understanding is always contested and future directed in ways oriented by what is at issue and at stake in those conflicts.

The book is motivated by a specific conception of the current situation in the philosophical understanding of naturalism. The most pressing challenge for naturalism today is to show how to account for our own (p.7) capacities for scientific understanding as a natural phenomenon that could be understood scientifically. Naturalist views that cannot meet this challenge would be self-defeating. The principal claim of the book is that meeting this challenge requires substantial, complementary revisions to familiar philosophical accounts of both of its components: how to situate our conceptual capacities within a scientific understanding of the world and what a scientific conception of the world amounts to. The two parts of the book develop a broad overview of these revisions and their rationales. These are relatively new approaches to the issues, and much work remains to be done on both sides. In the first part of the book, I reconsider how to think philosophically and scientifically about conceptual understanding. In place of more familiar appeals to a functional teleology of cognitive or linguistic representations, I emphasize the normativity of discursive practice within an evolving developmental niche and take both language and scientific practices to exemplify the evolutionary process of niche construction. In the second part of the book, I reconsider the sense of scientific understanding embodied in naturalists’ core commitment to situating philosophical work within a scientific conception of the world. The ongoing practice of scientific research encompasses the relevant form of scientific understanding; efforts to extract an established body of scientific knowledge from that practice are among the philosophical impositions upon science that naturalists should reject. The two parts of the argument are presented sequentially, but they should be understood as mutually reinforcing. The first part situates conceptual understanding within a scientific conception of nature. The second part explicates what it is to have a scientific conception of nature in terms of that account of conceptual understanding. This preliminary chapter prepares the ground by working out the conception of our current philosophical situation as aspiring naturalists, which motivates the remainder of the book.

II—Sellars and the Prospects for Philosophical Naturalism

Wilfrid Sellars (2007, ch. 14) provocatively framed contemporary philosophical discussions of naturalism by recognizing tensions between two alternative conceptions of human beings and our place in the world. The philosophical tradition has inherited what Sellars calls the “manifest image” of ourselves as persons whose involvement in the world incorporates sentient experience, conceptual understanding, and rationally reflective agency. A different self-conception emerged from the natural (p.8) sciences, even though the sciences arose as exercises of our “manifest” capacities. This emergent “scientific image” takes our life activities and achievements to be comprehensible without residue in theoretical terms drawn from physics, chemistry, biology, and perhaps psychology and the social sciences. The manifest and the scientific images each purport to completeness and autonomy. The manifest image takes the world as the setting for our experience, understanding, and action, incorporating the scientific image in “manifest” terms as a rationally explicable achievement of human understanding. From within the manifest image, scientific understanding is accountable to sense experience and is only meaningful to and authoritative for us through a shared commitment to think and act in empirically accountable terms. From the other direction, the scientific image proposes that experience, thought, and action are explicable in theoretical terms drawn from the relevant scientific disciplines. For Sellars, both conceptions express insights we ought to endorse. Each is nevertheless comprehensive in ways that may leave no space for the other’s insights within its own account of our place in the world. Sellars thus identified a preeminent contemporary philosophical task as doing justice to the comprehensiveness and apparent autonomy of both images in a stereoscopically unified vision of ourselves in the world. Sellars also insisted that this stereoscopic conception should be naturalistic in a strong sense. An adequate fusion of the images should give priority to the scientific image, situating our self-conception as sentient, sapient, rational agents within the horizons of a scientific conception of ourselves as natural beings.

Despite the prominence of W. V. O. Quine as an advocate of naturalism, Sellars’s philosophical vision predominantly sets the terms in which naturalism is nowadays conceived and discussed. First, Sellars recognized that naturalism cannot simply culminate in the replacement of philosophy by some empirical scientific discipline, as Quine proposed that scientific psychology might replace epistemology. Philosophical questions go beyond the interests and the locus of the various scientific disciplines. Sellars’s expression of the distinctively philosophical task in relation to the sciences is well known: “to understand how things in the broadest possible sense of the term hang together in the broadest possible sense of the term” (2007, 369). That task receives a more determinate form, however, in Sellars’s aspiration to account for the legitimate insights of both the manifest and the scientific images. The manifest image locates us within the “space of reasons” in which normative authority is constituted, including the normative authority of science itself. In understanding and expressing normative authority, however, philosophy (p.9) does not further describe or explain things but instead articulates and contributes to a shared project. A naturalist will of course conceive that philosophical project in ways that rely upon scientific understanding, and that do not claim independent authority over scientific inquiry, but will not be able to dispense with philosophical work.

Sellars’s conception of a naturalistic philosophy was also influential in two further respects. For Quine, the primary task of scientific theory is descriptive. The psychological theories that would replace epistemology aim to describe how we actually construct systematic and far-reaching scientific theories from a meager base of evidence. Sellars offered a more expansive conception of scientific aspirations. Science aims to explain what happens in the world. The priority that Sellars accords to the scientific image derives from its greater explanatory power: science enables us to understand and explain as well as describe the phenomena within its purview. This difference in turn accounts for the more expansive intellectual resources that Sellars accords to the scientific image. Whereas Quine would restrict science and philosophy to the most austere theoretical vocabulary sufficient to characterize actual events and dispositions, Sellars insists that the modal locutions of scientific laws are indispensable. The philosophical rehabilitation of modal language and inference from empiricist critics is a much longer story than I need to tell here.3 One clear outcome of that rehabilitation, however, has been to lead most naturalists toward Sellars’s conception of the scientific image as a framework of explanatory laws rather than Quine’s vision of efficiently systematized resources for theoretical description.4

Sellars not only set the terms in which most naturalists understand the scientific image and its philosophical authority, however. His work also guided several prominent challenges to naturalism. In his provocatively titled book The Scientific Image, for example, Bas van Fraassen (1980) proposed an epistemological challenge to Sellars’s naturalism on two fronts. He first argued that the explanatory power of the scientific image does not confer upon it a philosophical priority over the manifest image of ourselves as rational knowers and agents. Explanation is only a (p.10) pragmatic virtue responsive to contextually specific questions and concerns and cannot sustain the ontological priority naturalists ascribe to the scientific image. Second, van Fraassen argued that a scientific conception of the world should remain tethered to its rational accountability to human observation, even though the conceptual content of scientific theories legitimately outruns the limits of human observation. As rational agents with limited sensory access to the world, we should only believe what our best scientific theories tell us about what we can observe. Accepting van Fraassen’s constructive empiricism would thereby restore philosophical priority to the manifest image as the source of rational epistemic norms to which the scientific image must answer. Empiricist epistemology would set limits to scientific understanding.

Several of Sellars’s former colleagues at the University of Pittsburgh defend the philosophical autonomy of the manifest image by a different route. Unlike van Fraassen, John McDowell, Robert Brandom, and John Haugeland would not legislate rational constraints upon the scope of scientific beliefs. Indeed, their work shifts the primary philosophical concerns with science away from epistemology. These “left-Sellarsians”5 instead seek to comprehend the normativity of conceptually articulated understanding. Each situates conceptual normativity within the manifest image of ourselves as reflective rational agents. Each places scientific understanding among our most important achievements as concept users but regards its explanatory resources as insufficient to understand the normative authority that constitutes an intelligible “space of reasons.” To be sure, our self-conception as rational agents who answer to norms must be consistent with our self-conception as scientifically explicable natural beings. They see nothing mysterious, ineffable, or metaphysically transcendent about conceptual normativity and to that extent espouse a minimalist naturalism. Yet that consistency is a rational demand we should impose upon ourselves from within the space of reasons.

(p.11) The opening of a conceptually articulated space of reasons, although identifiable in retrospect as an event within a natural history of the human species, cannot be properly understood in terms of its natural history or of the laws, causes, or symmetries that govern it. Moreover, from within the space of reasons we can then recognize scientific understanding as only one among many domains of conceptually articulated human activities or achievements, each normatively accountable in its own characteristic ways.

Other critics prominently challenge philosophical naturalism in a different, more limited way by arguing that consciousness, sensory experience, moral obligation, aesthetic judgment, religious transcendence, or some other aspect of the world resists assimilation within a scientific understanding of nature. Such criticisms nevertheless usually presuppose familiar conceptions of scientific understanding in order to argue for their limits. Van Fraassen and the left-Sellarsians thus challenge naturalism in a deeper way. They do not merely discern residual pockets of resistance to an otherwise inclusive scientific conception of the world. They instead conclude that a comprehensively natural-scientific conception of the world would render incomprehensible the authority of the scientific image itself. Van Fraassen would revise a Sellarsian conception of the scientific image to acknowledge limits upon reasonable belief. McDowell, Brandom, and Haugeland challenge the philosophical priority of the scientific image more comprehensively. They argue that a “baldly naturalistic” (McDowell 1994) conception of ourselves as part of nature as scientifically understood not only overreaches its empirical justification. A radically comprehensive naturalism would undermine its own intelligibility as a conception of the world. The scientific image and the understanding that it promises depend upon our capacities for conceptual understanding and its rational accountability. These very capacities for conceptual thought cannot be fully assimilated within the terms of a scientific understanding of nature.6 In chapter 5, I argue that the left-Sellarsians are right to focus philosophical attention upon conceptual capacities more generally rather than empirical justification. For now, my point is only that among contemporary philosophical critics of naturalism, they provide the most fundamental and far-reaching (p.12) challenge to the philosophical priority naturalists accord to scientific understanding.

I nevertheless take Brandom, McDowell, and Haugeland to advance the naturalist cause constructively despite their rejection of stringent forms of philosophical naturalism. By showing where currently influential versions of naturalism fall short, they highlight the requirements for a more adequate naturalistic self-understanding. Their critical arguments also focus attention upon an indispensable but challenging desideratum for any viable philosophical naturalism. If Sellars is right about the comprehensiveness of scientific understanding, then a crucial philosophical task for naturalists is to comprehend how the capacity to understand the world scientifically fits within the purview of that scientific conception. In pursuing that task, we cannot take for granted either the scientific terms in which nature and ourselves should be understood or any particular account of what it is to understand the world scientifically. Not only do the sciences continue to refine and develop our understanding of the world, but empirical and philosophical studies of the sciences in turn are refining and developing our conception of scientific understanding.

McDowell (1994) directly disputes this Sellarsian conception of our philosophical situation and the tasks it poses. A central theme of his lectures is that no constructive philosophical or scientific work is needed to grasp how conceptual capacities, including capacities for scientific understanding, are compatible with a scientific understanding of nature. McDowell first rejects in advance the possibility that the rational spontaneity of human conceptual capacities could ever become scientifically intelligible within a “disenchanted” conception of nature as governed by law. The effort to incorporate reason within nature must yield either a “bald naturalism” that repudiates conceptual normativity altogether or a philosophical revisionism that constructs an inadequate simulacrum of the conceptual domain in “disenchanted” terms. He then argues that no such efforts are called for. We are already entitled to a conception of “second nature” through which human animals are brought into language and cultural tradition as part of their normal development: “Second nature could not float free of potentialities that belong to a normal human organism. This gives human reason enough of a foothold in the realm of [natural] law to satisfy any proper respect for modern natural science” (McDowell 1994, 84). Only misguided philosophical anxieties could drive further inquiry into how rational spontaneity is grounded in human biological potentialities or suggest that such inquiry might constructively inform our understanding of science, nature, or reason. (p.13) McDowell thereby closes off further philosophical reflection or scientific inquiry into the relations between a scientific understanding of nature as the realm of law and the scope and character of human conceptual capacities. Despite his insistence upon a “standing obligation to reflect about the credentials of the putatively rational linkages that govern [active empirical thinking]” (1994, 12), McDowell repudiates that obligation at the point where first and second nature meet. He takes for granted both our received philosophical accounts of scientific understanding as the disenchanted realm of law and our received biological accounts of human organisms, which together inform his insistence that a more thoroughly naturalistic account of conceptual understanding cannot be satisfactory.

This book instead takes up the obligation for critical reflection upon human conceptual capacities at the very point where McDowell urges philosophical and scientific forbearance. My arguments in the book aim to advance a broadly Sellarsian philosophical naturalism by rethinking both the scientific and the manifest images in light of possibilities for their philosophical and scientific reconciliation. I aim to show how we might better situate our self-understanding as persons responsive to normative considerations within a broadly scientific understanding of nature that incorporates our conceptual capacities as natural phenomena. McDowell is right that our received conceptions of nature and science foreclose a more thoroughly naturalistic incorporation of scientific understanding within nature as scientifically understood. I take that conceptual impasse to call for renewed philosophical reflection and scientific inquiry rather than acquiescence. Such reflection and inquiry should also aspire to advance our self-understanding constructively and not merely to relieve recurrent philosophical anxieties about our conceptual footing in the world.

III—Reconceiving the Fusion of the Manifest and Scientific Images

A broadly Sellarsian philosophical project would overcome the apparent incompatibility of the manifest and scientific images by fusing them into a more coherent conception of ourselves and our capacities, which nevertheless acknowledges and accommodates the insights of both. My approach to that project is avowedly naturalistic in the sense that the resulting fusion incorporates our developed and developing capacities for scientific understanding within the natural world as scientifically (p.14) understood. Achieving a more adequately naturalistic self-understanding nevertheless requires some reformulation of the terms in which that task has previously been conceived. My reformulation is primarily responsive to new philosophical and empirical work arising from three directions. These developments bear upon one another in revealing and complementary ways, even though they are rarely considered together.

First, Haugeland, McDowell, and Brandom have further developed the “manifest” conception of ourselves as agents who perceive, understand, and act within the world as responsive to conceptually articulated norms. Their work thereby complicates as well as enriches the task of achieving a naturalistic fusion of the scientific and manifest images.7 Each of them takes his account of conceptual capacities to block any stringent or (in McDowell’s 1994 phrase) “bald” naturalism. They endorse a minimalist naturalism, arguing that nothing in their views is inconsistent with what we learn from the natural sciences. Conceptual normativity nevertheless remains autonomous in their view, without need or expectation of further scientific explication. This opposition to a more thoroughgoing philosophical naturalism presumes familiar conceptions of scientific understanding, however, and also does not consider some new theoretical and empirical resources for a scientific account of our conceptual capacities. The other two developments guiding this book suggest that these presumptions are misguided.

A second body of work that centrally informs my project comes from recent philosophy of science and interdisciplinary science studies. This work offers compelling reasons to reconceive familiar accounts of scientific understanding exemplified by the Sellarsian scientific image. A central concern of philosophical naturalism has been to let the sciences speak for themselves, freed from the prejudices and constraints of inherited philosophical or other preconceptions. Naturalists’ widespread rejection of classical empiricist epistemology strikingly exemplifies this commitment. Empiricists are skeptical of concepts or claims whose content and justification are inferentially distant from what is observable (p.15) with human sensory capacities. Naturalists instead highlight the robust successes of theoretical science that appeal to unobservable entities or processes and argue that we should instead be skeptical of these empiricist scruples. If the best scientific research successfully draws upon a richer set of conceptual and methodological resources than empiricist epistemology would countenance, so much the worse for empiricist epistemology.

Van Fraassen’s challenge to naturalists arose from this clash between scientific practice and empiricist presuppositions; he sought to restore the governance of empiricist epistemological norms over the scientific image. I draw an opposing moral from recent work in philosophy of science and science studies: naturalist criticism of empiricist epistemology has not yet gone far enough. The predominant philosophical conception of the scientific image still reflects a long-standing philosophical preoccupation with epistemology, which is in tension with the practices and achievements of the sciences. Recent philosophical, social, and historical studies of science shift attention away from scientific knowledge as a detachable product of inquiry, focusing instead upon the ongoing articulation and development of scientific practices. An important aspect of this shift is temporal. The temporal orientation of epistemology is largely retrospective: To what extent is an already established body of scientific knowledge claims reliable or justified?8 Yet that retrospective orientation is at odds with the practical orientation of scientific research. Scientists are also concerned with questions of justification and reliability, but from a different direction. Their work is governed by the prospective orientation of a research program, and they want to know whether and how past practice can successfully guide further exploration and disclosure of the world that will likely revise that guiding understanding. Philosophical and empirical studies of the sciences thereby encourage reconceiving the scientific image as incorporating a situated practical capacity to extend and refine current understanding of ourselves-in-the-world rather than consisting in a systematic representation.

(p.16) The third primary resource for my reformulation of naturalism comes more directly from the sciences themselves. The emergence of the mid-twentieth-century evolutionary synthesis provided powerful new conceptual resources for philosophical naturalists. Evolutionary theory offered promising possibilities for understanding the normativity of knowledge and conceptual content in terms of genetic processes that secure biological adaptation to an organism’s environment. A neo-Darwinian conception of ourselves has thereby become central to the scientific image as we know it, both for naturalists such as Ruth Millikan (1984) or Daniel Dennett (1987, 1995) whose philosophical vision was explicitly evolutionary and for others for whom evolution merely provided a broader horizon for their accounts of intentionality and knowledge. New theoretical developments within evolutionary theory (e.g., developmental evolution, developmental systems theory, ecological-developmental biology, and niche construction theory), along with new empirical work on animal behavior, human evolution, and language, now challenge familiar ways of thinking about cognition and knowledge in evolutionary terms and suggest alternative approaches for situating human understanding within our evolutionary trajectory. Philosophical naturalism commits us to maintaining an ongoing engagement with scientific work in this way without settling for familiar and congenial conceptual horizons that the sciences continue to surpass.

My interests in these three projects arose independently. Left-Sellarsian accounts of conceptual normativity, philosophical and empirical work on scientific practice, and the extended evolutionary synthesis (Müller and Pigliucci 2010) each stands on its own as a well-developed line of inquiry. All three bodies of work are nevertheless mutually supportive in ways that strengthen the case for reformulating a naturalistic fusion of the manifest and scientific images. Their constructive contributions to understanding conceptual normativity and scientific practice encourage thinking differently about ourselves and our capacities for understanding the world scientifically. They also help us recognize and overcome residual theological or “supernatural” commitments that still shape avowedly naturalistic projects in philosophy, science, and science studies. In this respect, the convergence of these ways of thinking about ourselves and the sciences from within a scientific understanding of nature promises a more thoroughly naturalistic conception of ourselves and the world.

This approach to a naturalistic fusion of the manifest and scientific images draws together several mutually reinforcing themes. One theme is the need to reorient the place of scientific understanding within the (p.17) manifest image of ourselves as persons responsive and accountable to norms. A familiar conception of science emphasizes its role in justifying belief; we are accustomed to thinking of ourselves as believers who formulate and accept representations of how things are. The meaning and justification of those beliefs would then be the primary target for philosophical explication and assessment. Sellars, Brandom, McDowell, Haugeland, and others within this tradition suggest a different conception of ourselves, which also changes the central tasks for science and philosophy. We are concept users who engage others and our partially shared surroundings in discursive practice. The primary phenomenon to understand naturalistically is not the content, justification, and truth of beliefs but instead the opening and sustaining of a “space of reasons” in which there could be conceptually articulated meaning and justification at all, including meaningful disagreement and conceptual difference. This “space of reasons” is an ongoing pattern of interaction among ourselves and with our partially shared surroundings. As Ian Hacking once noted, “Whether a proposition is as it were up for grabs, as a candidate for being true-or-false, depends on whether we have ways to reason about it” (2002, 160). The space of reasons encompasses not only the claims that we take to be true or false but also the conceptual field and patterns of reasoning within which those claims become intelligible possibilities whose epistemic status can be assessed. Any determination of the content, justification, or truth of beliefs emerges from that larger process of ongoing interaction. Whether conceived as second nature (McDowell 1994), discursive practice (Brandom 1994), constituted domains (Haugeland 1998), or a functional linguistic pluralism (Price 2011), the space of reasons cannot be reduced to the various contents expressed or expressible within it. The familiar epistemological conception of us as believers, who might ideally share a common representation of the world in the scientific image, thus conflates particular moves within discursive practice or the space of reasons with the space or practice itself.

A product-oriented conception of scientific understanding might appeal to the concept of a language (including a language of thought if there were such a thing) to express this difference between the space of reasons and the claims that can be assessed within it. We could then distinguish beliefs within a language from the language itself as a larger space of possibilities within which those beliefs can be intelligibly expressed and assessed.9 As we shall see, however, this appeal to the determinate (p.18) structure of a language in place of the dynamic configuration of a space of reasons is not adequate for multiple reasons. Utterances or marks only become linguistically interrelated through their place within discursive practice, which extends beyond language to incorporate perception and action. Moreover, appeals to language as the horizon within which beliefs acquire content inappropriately reify a structure abstracted from the dynamics of ongoing discursive interaction. Above all, such a conception mistakenly separates language, taken as a space or structure of possible representations of the world, from the world to which it is semantically accountable.10

Recent work in evolutionary biology and the philosophy of biology resonates with this shift of attention away from beliefs as mental or linguistic representations toward a conception of discursive practice or the space of reasons. Earlier philosophical work on the evolution of cognitive capacities tended first to focus upon “intelligence” as a general cognitive capacity and more recently upon the functional and adaptive role of mental representations within the behavioral economy of an organism’s way of life. Whether taking language and conceptual understanding as continuous with the cognitive capacities of many nonhuman animals or as marked by a sharp break due to the symbolic or recursive character of language, philosophers have typically construed the cognitive capacities of animals (including human animals) in terms of self-contained abilities for perceiving, representing, and responding to the world “external” to the organism.11

This entrenched way of thinking about cognition as self-contained becomes increasingly problematic biologically, with closer attention to the developmental, physiological, and evolutionary entanglement of organisms with their environments. The resulting reconceptions challenge (p.19) traditional cognitive internalism from two different directions.12 Understanding the close intertwining of organisms’ sensory systems with their repertoires for behavioral and physiological responsiveness shows how organisms are closely coupled with their environments. An organism’s biological environment does not consist of objectively independent features of its physical surroundings. Biological environments are bounded and configured as the settings to which organisms’ ongoing way of life is responsive. An organism’s environment consists of those features or aspects of its surroundings that matter to its development, physiology, reproduction, and consequent evolution across generations. The organism and its way of life can in turn only be explicated as part of a larger biological pattern that encompasses its environment.

Understanding this close coupling of organism and environment shows how some organisms can develop robust capacities for tracking and flexibly responding to multiple environmental features, which can account for very sophisticated responsiveness to variable environmental conditions without postulating representational intermediaries (Sterelny 2003). Such perceptual and practical capacities are adaptively directed toward and responsive to a selective configuration of the organism’s physical environment.13 These capacities nevertheless contribute to organisms’ behavioral and physiological economy in ways that do not differentiate how the organism takes its surroundings to be (which might be mistaken) from what we can provisionally call an extensional determination of those aspects of its physical and behavioral surroundings to which its way of life is responsive.14 Organisms are selectively oriented toward aspects (p.20) of their surroundings without also taking them in or as some determinate conception.15 The recognition that organism/environment coupling is selective but not conceptually articulated might seem initially to sever the connection between nonhuman organisms’ perceptual/practical involvement with their surroundings and our own conceptually articulated intentional directedness. Proposing a sharp divide between human and nonhuman cognition might then seem to conflict with a naturalistic emphasis upon understanding us as animals in evolutionary continuity with our primate kin.

The development of niche construction theory (Odling-Smee, Laland, and Feldman 2003) and its application to understanding the evolution of language and symbolic-conceptual understanding (e.g., Deacon 1997; Dor and Jablonka 2000, 2001, 2004, 2010; and Bickerton 2009, 2014) restores this connection in a way that reinforces the left-Sellarsian turn from mental representation to public discursive practice. Niche construction is the transformation of the developmental, selective environment of an organism and its lineage by ongoing, cumulative interactions of other organisms with that environment. The biological environment of an organism’s lineage thus is not simply given but is instead dynamically shaped by ongoing interaction with the organisms in that lineage. Such transformations are not limited to enduring physical effects on the abiotic environment but also include persistent forms of behavioral niche construction. Behavioral niche construction requires only that the presence of behavioral patterns, and their selective significance for individual organisms’ evolutionary fitness, be reliably reproduced in subsequent generations.16 The emergence of (p.21) communicative-cooperative practices that evolve into language is a preeminent example of niche construction. Language is a persisting public phenomenon that coevolves with human beings. Human beings normally develop in an environment in which spoken language is both pervasive and salient, while languages only exist in gradually changing forms that can be learned and thereby reproduced. Human abilities to acquire and take up the skills and discriminations that enable the ongoing reproduction of that phenomenon are integral to our overall practical/perceptual responsiveness to our environment, which has thereby become a discursively articulated environment. The evolutionary emergence of this capacity and its ontogenetic reconstruction in each generation rely on the same close coupling with our discursively articulated environment that characterizes other organisms’ capacities for perceptual and practical responsiveness to their selective environments. There is nothing mysterious or even discontinuous about the gradual development of the linguistic capacities and performances that enable conceptual understanding. Yet the only partial autonomy of discursive practice from systematic interconnectedness with other aspects of our perceptual-practical immersion in an environment allows for the emergence of symbolic displacement and conceptual understanding.17

Conceptual understanding thus emerges biologically as a highly flexible, self-reproducing and self-differentiating responsiveness to cumulatively constructed aspects of our selective environment. Discursive niche construction is not limited to our abilities to perceive and produce linguistic expressions. Other symbolically significant expressive capacities (e.g., pictorial, musical, corporeal, equipmental, and more) are also integral forms of human niche construction.18 More important, however, is that the resulting capacities for symbolic displacement also incorporate practical-perceptual immersion in an environment. Our perceptual and practical capacities are not themselves different in kind from those of other organisms, but they are transformed by their uptake within discursive practice. McDowell (1994) characterizes the possible discursive significance of everything we do as “the unboundedness of (p.22) the conceptual.” Our discursively articulated practical/perceptual involvements are pervasive throughout and integral to the world in which we develop as and into adult human beings. Their cumulative effects dramatically transformed us as a species and indirectly affected many others, including some thereby driven to extinction. The verbally articulated differences that are so central to our developmental, selective environment are nevertheless almost entirely opaque to our various “companion species” (Haraway 2008) and, to that extent, not part of their biological environments. Our inherited responsiveness and massive ongoing contribution to this peculiar cumulative history of niche construction, and not any general cognitive capacities, are what primarily differentiate us as concept users from any other known organism.19

The emergence of scientific inquiry within the recent history of the human species has contributed extensively and intensively to our ongoing niche construction. Philosophical attention to these contributions was long focused primarily upon the production and justification of scientific knowledge. New philosophical studies of scientific practice, augmented by the rapid growth of empirical research on scientific practice in multiple disciplines, have now emerged alongside traditional epistemology and epistemological philosophy of science. Studies of scientific practice promise constructive mutual engagement with both the left-Sellarsian philosophical tradition and the emerging understanding of discursive practice as a form of evolutionary niche construction.

Studies of scientific practice share with the left-Sellarsians a primary focus upon the articulation of conceptual understanding rather than the justification of knowledge claims. Quine’s famous image of science as a “totality of knowledge or beliefs [that] is a man-made fabric which impinges on experience only along the edges” (1953, 42) exemplifies the widespread construal of scientific knowledge as composed of systematically interrelated statements. Recent work on scientific practice revises and expands this familiar embodiment of the scientific image. Attention to scientific practice challenges familiar conceptions of theories as systematic sets of statements. Scientific understanding is instead mediated (p.23) by mathematical, visual, physical, verbal, and other kinds of models (Morgan and Morrison 1999) and by the coordination of such models with laboratory phenomena that display the conceptual relations that the theories express. The experimental systems used in research also serve as models of a scientific domain in ways that affect which conceptual relations can show up clearly in that context.20 The models employed are often mutually inconsistent and overlap in their domain of applicability while also leaving gaps where no models adequately articulate theory (Giere 1988; Cartwright 1999; Wilson 2006). Theoretical understanding encompasses not merely a grasp of truth claims but also abilities to use and extend the standard models and to recognize which models are appropriate for which situations and purposes. Studies of the role of discipline formation and conceptual exchange across disciplinary boundaries in shaping the conceptualization of scientific domains (e.g., Bono 1990; Bechtel 1993; Galison 1997; Lenoir 1997; Rheinberger 1997) have gone further beyond the more limited scope of epistemological conceptions of scientific understanding. These extensive patterns of discursive exchange also embed scientific practices in larger patterns of cultural practice and understanding, which further contribute to the content and significance of scientific understanding.21

In more traditional accounts of the scientific image, laws of nature often distinguish the domain of nature from the forms of social and cultural life that have emerged within it. Kant’s distinction between phenomena governed by natural laws and thoughts and actions governed by a rational conception of laws that we give to ourselves is an influential precursor in this respect to Sellars’s distinction of the scientific and manifest images. In chapter 8, I argue that from the standpoint of scientific practice, “laws of nature” are best understood as scientific laws expressing commitments undertaken and deployed in scientific reasoning in various contexts of inquiry (Lange 2000a, 2007).22 Such reasoning is (p.24) integral to our ongoing interaction with our environment, however, in ways that further articulate it discursively. Understanding laws within scientific practice can thereby help conjoin the manifest and scientific images rather than to divide them.

The proposal that different laws of nature are salient and authoritative within different domains of scientific practice exemplifies a more widespread recognition of the disunity of scientific practice and understanding (Dupre 1993; Galison and Stump 1996; Cartwright 1999; Lange 2000a; Hacking 1992; Wilson 2006; Giere 2006; Bechtel 1993). Here we encounter a fracture in recent philosophical discussions of naturalism that will play an important role in the book. In many areas of recent philosophy (e.g., metaphysics, epistemology, philosophy of language and mind, ethics), naturalists and their critics mostly take for granted that scientific understanding aspires to the comprehensiveness suggested by Sellars’s account of the scientific image. Philosophers of science, however, often regard naturalism as guiding our understanding of the sciences in a different direction than naturalism as conceived elsewhere in philosophy. Emphasizing naturalists’ commitment not to impose philosophical preconceptions or constraints upon the sciences, they often take at face value “science as we know it: apportioned into disciplines, apparently arbitrarily grown up; governing different sets of properties at different levels of abstraction; pockets of great precision; large parcels of qualitative maxims resisting precise formulation; here and there, once in a while, corners that line up, but mostly ragged edges; and always the cover of law just loosely attached to the jumbled world of material things” (Cartwright 1999, 1).

Recognition of disunity among the sciences may then seem to threaten the very idea of a comprehensive “scientific image” and with it the notion of a stringent philosophical naturalism. If the sciences yield powerful insights but only within patchy, relatively disconnected domains of inquiry, then perhaps only a minimalist naturalism is called for. Naturalists could take scientific understanding to be authoritative wherever it can be achieved but would not expect its authority to extend everywhere. The supposed need to accommodate a scientific understanding (p.25) of nature within nature as scientifically understood might then also dissolve; there would be no reason to expect scientific work in its messy complexity to be among the phenomena readily accessible to natural scientific understanding. I endorse and draw upon many of the “disunifiers’” claims about scientific practice and understanding but draw a different inference. We need to reconceive rather than abandon the comprehensiveness of scientific understanding. We can recognize the kinds of disunity that science studies research has rightly identified while also recognizing an indispensable mutual openness and accountability across the various domains of scientific work. The result, introduced in chapter 6 and developed throughout part 2, is a different sense of how scientific understanding is comprehensive. Scientific understanding “as a whole” yields neither a unified theoretical representation of the world nor a disconnected collection of disciplinary practices but instead articulates and refines the space of reasons as interconnected and indefinitely extensible.23

This conception of scientific practice suggests that we understand the sciences themselves as part of our ongoing niche construction in ways that conjoin the material and behavioral-discursive reconstruction of our developmental environment. The establishment of reliable, reproducible experimental phenomena that manifest clear patterns in the world plays a significant role both in the articulation of specific scientific concepts and in opening whole domains of scientific work to conceptual articulation and understanding. Moreover, the development of various kinds of models—physical models, visual diagrams or images, mathematical models, and more—is integral to the articulation of conceptual understanding. Scientific conceptual understanding is never just a matter of “mental” representation but always involves changing the world around us in ways that enhance its intelligibility. These changes take many forms: rearranging things to reveal informative patterns in the laboratory and the world outside it, building and deploying new kinds of models in new ways, or extending and refining the inferential entanglements of scientific concepts and other discursive elements with other domains of discursive practice. Moreover, these material transformations of the world’s intelligibility are not merely important as aids to (p.26) initial discovery or subsequent pedagogy. Many uses of well-established scientific concepts beyond the laboratory require transforming the circumstances of application to resemble sufficiently the laboratory or other experimental settings where the relevant conceptual distinctions were developed and stabilized (Latour 1983; Rouse 1987). This role for experimental, technological, and metaphorical activity in conceptual understanding reinforces the notion that conceptual articulation is a phenomenon of niche construction through which we inherit, reproduce, and extend physical and behavioral transformations of the world that allow it to be intelligible in new ways.24

These conceptions revise the scientific image in ways that undercut Sellars’s original metaphorical use of the term ‘image’ for a scientific conception of the world. On the conceptions of science and naturalism proposed in this book, the sciences do not offer a systematic representation of the world as a whole, even as a promissory note. They instead make a decisive contribution to our ongoing efforts to transform our environmental niche in ways that allow it to be conceptually intelligible, and these forms of intelligibility are integral to the ongoing natural history of our species. The sciences introduce new experimental systems, practices, and skills, their technological extension both within and beyond the research context and conceptual revisions that engage and mutually transform other discursive practices. They develop new models and more general theoretical formulations along with the mathematical and other inferential understanding needed to work with them. They raise new conceptual and practical issues that people must respond to in various ways, including closing off some ways of thinking and acting that once seemed intelligible and attractive. Together they help reconstitute a space of intelligible possibilities for understanding and articulating ourselves and the world, including possibilities for reasonable disagreement. The concepts developed and deployed in those practices are always only partially determinate, open to more extensive and intensive articulation and inferential development with respect to other aspects of our discursive involvement in the world. This (p.27) open-endedness is not only a matter of human limitation. Part of what the sciences open and sustain is a grasp of scientific significance within a broader intellectual and cultural milieu such that some truth claims matter more than others and matter to us in different ways. This dimension of scientific significance does not simply involve the shaping of inquiry by prior interests and involvements, however, for our interests and involvements are also themselves always at issue for us. In recognizing scientific understanding as materially and conceptually shaping the world we live in, as our biological environment, we understand both our vulnerable dependence upon our worldly circumstances and our openness to partial self-transformation. Just what a human way of life is, and could become, is ultimately part of what is at issue for us in our ongoing niche construction. Understanding both our situated dependence upon a historically evolving environment and our partial openness to remaking our way of life within that world is the most important outcome of recognizing how our biological niche is also a conceptually articulated space of reasons.

IV—Advancing a Naturalistic Self-Understanding

My project of working out and defending a revised conception of the scientific image and its place within a naturalistic self-understanding is also situated within this historically constituted conceptual space. Philosophical naturalism is an evolving project whose characterization is itself at issue in ways that are accountable to its own history and its prospects for further development. The issues relevant to defending or opposing naturalism, and how their resolution matters, are shaped by a tradition within science, philosophy, and science studies as an intelligible space of reasoning and understanding. The justification for understanding philosophical naturalism and the scientific image in the ways I propose is that it responds constructively to recognized conceptual and empirical issues within that tradition, brings out significant new concerns and ways of addressing them, and does both in ways that open new possibilities for further development and refinement.

How does my reformulation of philosophical naturalism claim to answer more adequately to the issues that have emerged within naturalism as a historical project? A central consideration within the naturalistic tradition is the rejection of “first philosophy” and the consequent insistence that philosophy should take direction from our best scientific (p.28) understanding of the world rather than impose philosophical preconceptions upon the sciences. That distinction nevertheless has a contested history. As one prominent example, an empiricist epistemological stance has long been associated with a scientific conception of the world, from Locke through Mach, Neurath, and Quine, to van Fraassen. Philosophers now increasingly recognize that empiricism is not coextensive with a scientific conception of the world, however, but instead might be a philosophical orientation imposed upon science. Naturalism and empiricism provide opposing philosophical orientations.

Sellars’s original conception of the scientific image as a systematic theoretical representation is also a dispensable philosophical imposition that the sciences do not need and perhaps do not even accommodate. The sciences do seek to develop retrospective compilations and systematizations of scientific understanding in multiple contexts: textbooks, review articles, encyclopedias, handbooks, policy analysis, or more locally in efforts to find common ground for an interdisciplinary collaboration. In each case, the retrospective compilation of the current state of knowledge is partial, perspectival, and oriented toward a task at hand. Yet there may then be no need, and no scientific basis, for how to specify the scientific image in the form of a general, all-encompassing scientific representation for no purpose in particular. Indeed, there may be real conflict between the sciences and a philosophical conception of a unified theoretical representation of the world as a whole. The sciences often employ mutually inconsistent treatments of similar situations, which cannot be accommodated within a single, consistent theoretical representation. Moreover, the sciences incorporate a significant range of disagreement. Even where they seek the resolution of specific disagreements within or among disciplines, that resolution may open up further issues not resolvable in the same way. In this respect, a conception of scientific practice as encompassing room for legitimate disagreement within and across various scientific disciplines, theoretical orientations, or research programs seems a more appropriate stance for naturalists. Empirically, the expectation that an expression of contemporary scientific understanding would take the form of a systematically unified theoretical “image” of the world seems not to accord with how scientific work is actually done. A conception of the scientific image in these traditional terms may thus fall short of naturalistic deference to science, as does the empiricist hostility to unobservable entities that once seemed to define a “scientific conception of the world” for many philosophers. Both may instead be a vestige of long-standing philosophical commitments to epistemology as “first philosophy” (Quine 1965).

(p.29) The turn to scientific practice also better accommodates the empirical contingency of scientific understanding. Naturalists’ commitment to be guided by the best contemporary scientific understanding brings with it a recurrent temptation to reify its terms, concerns, disciplinary orientations, and methodological strategies and constraints. The synecdoche that would mistakenly identify a scientific conception of the world with its most recent incarnations blocks an important virtue that naturalism should promote—namely, openness to empirical discovery, conceptual innovation, and their possible challenge to familiar ways of life and ways of thinking. Arthur Fine succinctly characterized this important aspect of naturalists’ commitment not to countenance philosophical impositions or constraints upon the sciences, even though he does not explicitly identify it with naturalism: “[The Natural Ontological Attitude] sees … science as a set of practices with a history. That history constrains our understanding of current practice and structures our evaluation of promising problems and modes of inquiry. Because the practice is varied and self-reflective, it encompasses the possibility of moving on in virtually any direction that can be rationalized in terms of current practice and past history” (1986a, 10). This book’s conception of a scientific understanding of the world (the scientific image) builds such conceptual and methodological open-endedness into our understanding of the sciences.

Insistence upon the conceptual and methodological open-endedness of scientific understanding points toward another important aspect of the naturalism advocated here. Despite rejecting familiar conceptions of the scientific image as a comprehensive theoretical representation of the world, I still insist upon a residual sense in which scientific understanding remains comprehensive. In this respect, the naturalism I advocate is partially at odds with the more minimalist forms of naturalism promoted by the left-Sellarsians and for different reasons by many of the advocates of scientific disunity. The sense in which a naturalistic self-understanding remains both comprehensive and comprehensively scientific can be seen from two complementary directions. The first is that our way of life as a biological lineage shares a single, comprehensive biological niche for all its internal variegation. We are mutually dependent upon and vulnerable to one another and our shared environment for whether and how that way of life will continue. The second is that the conceptual character of our discursive practices, including scientific practices, depends upon their significance for, and openness to challenge from, what we say and do in other aspects of our lives. The “space of reasons” is and must be a unified space. This sense of the constitutive (p.30) comprehensiveness of conceptual understanding generally, and scientific understanding specifically, depends upon the specific arguments developed below, especially in chapters 7 and 10. Two points are important to make now, however, both for understanding my commitment to naturalism and for foreshadowing an important line of argument in the book. First, these two ways of understanding the comprehensiveness of the scientific image make the same point from different directions. On the view developed in this book, our biological environment and the conceptually articulated space of reasons are the same natural phenomenon. Second, part of the importance of recognizing the unity and comprehensiveness of conceptual space is that it blocks the temptation to insulate our various scientific practices and other aspects of our way of life from one another. ‘Naturalism’ has long been a “fighting word,” often motivated by challenges to various claims or practices as inconsistent with or inappropriate for our self-understanding as natural entities. More minimalist naturalisms can too readily shield various conceptual or practical domains (including scientific practices) from such criticism by allowing them too much autonomy. On the view developed in this book, it matters to discursive practices generally, and scientific understanding specifically, that their conceptual autonomy is only partial. They remain accountable to other discursive practices and to their involvement within our partially shared way of life. In this way, the Sellarsian conception of a naturalistic philosophy as aspiring to understand “how things in the broadest possible sense of the term hang together in the broadest possible sense of the term” takes on renewed importance.

This way of accounting for scientific understanding as part of nature scientifically understood also calls attention to other possibly non-naturalist vestiges within some alternative conceptions of naturalism. A comprehensive-representational conception of the scientific image may no longer need or permit reference to God. Yet the very idea of a systematic theoretical representation of the world as a whole may still express a theological understanding of the standpoint of scientific knowledge. God’s understanding would represent the world from a standpoint outside of the world represented, and scientific understanding is too often conceived as aspiring to a comparably external position (what McDowell [1994] sometimes describes as a view from “sideways on”). To the extent that scientific understanding is conceived as having determinate content intralinguistically, apart from its involvement in broader patterns of material interaction with the world, for example, it may still aspire to such an external, “sideways-on” conception of the world. Such accounts might also violate naturalistic commitments by thinking of (p.31) concepts as having “immaculate” content, freed from any bodily or worldly entanglements.25 Efforts to remove conceptual contents and norms from their embeddedness within a scientifically understood natural world have a long history. These efforts include Descartes’s conception of “thinking substance” as noncorporeal, Kant’s account of action and belief as noumenal in answering to a conception of law rather than to laws of nature, Husserl on transcendental consciousness as a “region of being” outside of nature, Frege’s and other quasi-transcendental conceptions of logic as laws of pure thought, and uses of the distinction between computer hardware and software as models for the supposed immateriality of thought. In thinking of scientific practice as part of the natural history of discursive niche construction, we can instead advance further toward a thoroughly worldly, naturalistic conception of our own capacities to understand ourselves and our surroundings: scientific understanding articulates the world from within rather than representing it from an imagined external standpoint.

Some accounts of scientific understanding that aspire to a naturalistic conception also lapse into a fideistic conception that marks its origins within a Christian theological tradition. Why should a commitment to scientific understanding be expressed as “belief in” a systematically expressed body of scientific doctrine in whole or part? A scientific understanding of the world commits one to working with the conceptual resources provided by scientific practices but may only require that one work within a partially shared conceptual space. In many contemporary collisions between scientific understanding and theological commitments, naturalists already concede too much to their theologically minded opponents in accepting questions about what to believe as appropriate expressions of scientific understanding. Paralleling Nietzsche’s acerbic response to the residually Christian moral commitments of nineteenth-century atheistic freethinkers such as George Eliot, we might conclude that many philosophical naturalists today “are rid of the Christian God and now … all the more firmly … cling to Christian [epistemology]” (Nietzsche 1954, 515).

These suggestions for how we might revise the scientific image to conjoin it with a conception of ourselves as rational concept users are still (p.32) only promissory notes. The remainder of the book pursues this strategy for how to conceive scientific understanding as itself part of nature as scientifically understood in two parts. The first part develops an account of intentionality and conceptual normativity as scientifically comprehensible phenomena. chapter 2 sets the stage by reviewing some of the principal dividing lines in philosophical accounts of intentionality and conceptual normativity and providing initial arguments for the strategy undertaken in what follows. This philosophical strategy has two characteristic features: First, it begins with practical and perceptual interaction with the world and asks how that interaction can become conceptually articulated, rather than beginning with representational or inferential content and then asking how that content is fulfilled or disconfirmed in perception and action. Second, it understands such conceptually articulated intentional directedness as a normative status within discursive practice rather than an operative process in cognition. chapters 3 and 4 then develop a single extended line of argument for understanding language, thought, and other conceptually articulated performances as forms of behavioral niche construction that have coevolved with human ways of life. Conceptually articulated understanding is part of our natural history as a lineage, marked by a characteristically two-dimensional responsiveness to a changing developmental, ecological, and hence selective environment. This two-dimensionality differentiates the features of our environment to which we are responding with some performance from how we thereby “take” those features to be.

The first part concludes with chapter 5, which shows how to understand the normativity of our conceptual capacities in these terms. The chapter begins by distinguishing two approaches to the objective accountability of discursive practices. In contrast to traditional efforts to establish the epistemic objectivity of articulated judgments, Davidson, Brandom, McDowell, Haugeland, and others rightly give priority to the objectivity of conceptual content and reasoning. They nevertheless mistakenly attempt to understand conceptual objectivity as accountability to objects understood as external to discursive practice. A more expansive conception of discursive practice, as organismic interaction within our discursively articulated environment, shows how conceptual normativity involves a temporally extended accountability to what is at issue and at stake in that ongoing interaction. “Issues” and “stakes” are anaphoric concepts that enable reference to people’s mutual but partially incompatible directedness toward the future development of their ongoing practices and way of life. Most organisms act to maintain and reproduce their lineage through ongoing responsiveness to life-relevant (p.33) features of what thereby becomes their biological environment. Conceptually articulated ways of life are two-dimensional in the deeper sense that they are oriented not only toward continually maintaining their biological lineage but also toward determining what that way of life is and will be. This sense of two-dimensionality is “deeper” in that it enables those organisms to differentiate how they take their environment to be from how it is.

The second part of the book shows how to situate scientific practice within this account of conceptual understanding, yielding a corresponding reconception of the scientific image, which embeds scientific understanding within scientific practice. First and foremost, I argue in chapter 6, what the sciences provide is not a single, integrated position “within” the Sellarsian space of reasons. The sciences instead continually reconfigure the space of reasons itself, changing how aspects of the world are intelligible to us and which aspects stand out as scientifically and culturally significant. They do so not merely by changing how we think and talk about the world theoretically, as I argue in chapter 7. Experimental practice makes important contributions to conceptual articulation in the sciences by creating phenomena that allow new aspects of the world to be intelligible. New ways of thinking and talking would make no sense apart from the experimental systems that mediate the applicability of scientific concepts and models. The sciences allow the world to show itself intelligibly in new ways in significant part by making new things happen. It is in this sense that scientific understanding articulates the world itself, rearranging it in ways that allow new conceptual possibilities to emerge. That chapter also begins to develop my reasons for retaining a sense of the comprehensiveness of scientific understanding despite the apparent “disunity” of scientific-understanding-in-practice.

chapter 8 works out the modal character of scientific understanding. Instead of beginning with a philosophically determined conception of laws of nature, and then asking which sciences discover laws, the chapter follows Marc Lange and John Haugeland in asking what roles laws play in scientific practice and identifying as laws whatever plays those roles in a given science. Lange and Haugeland each make indispensable contributions to understanding the conjoined alethic-modal and normative dimensions of scientific understanding. Taken together, this conception of scientific laws shows why scientific concepts are developed within partially autonomous disciplinary domains. The holistic patterns of counterfactual stability that mark the “necessity” of laws within a scientific domain also establish domain-constitutive norms of scientific reasoning. The chapter then concludes by showing why we (p.34) should think of such laws neither as linguistic or mathematical representations nor as invariant patterns in the world apart from us but instead as more inclusive worldly patterns that also incorporate scientific practices of pattern recognition. We can thereby understand in a more detailed way why scientific understanding is a form of niche construction that changes the world and ourselves in ways that enable its novel forms of intelligibility.

chapters 9 and 10 together conclude the main argument of the book by showing how scientific understanding exemplifies the temporality of conceptual normativity discussed in chapter 5. chapter 9 shows how the sciences initially open new law-governed conceptual domains, which can nevertheless be already authoritative over scientific and other discursive practices, by developing “fictional” experimental or other practical contexts that come to exemplify conceptual norms. chapter 10 shows how scientific significance expresses a future-directed accountability to what is at issue and at stake in scientific practices and in the larger patterns of cultural niche construction to which they belong. Scientific significance accrues to both the “homonomic” conceptual development internal to a law-governed scientific domain and its “heteronomic” conceptual relations to other practices and concerns that indicate what is at stake in understanding that domain.

Taken together, these two parts of the book’s argument provide what I believe to be a coherent and more philosophically and empirically promising framework for a naturalistic self-understanding. An important part of the rationale for the book’s approach to recognizing conceptual understanding as a natural phenomenon and accounting for its normative authority is that this approach yields a more adequate account of conceptual understanding in scientific practice. Part of the rationale for this conception of scientific practice and understanding in turn is that it enables a more satisfactory conception of ourselves as part of nature as scientifically understood. I take this way of mutually calibrating our best scientific understanding of our own conceptual capacities with our best understanding of the practices and achievements of the sciences to be integral to the very idea of a philosophical naturalism. The concluding chapter of the book presents its constructive vision of naturalism and of the place of conceptual capacities and scientific understanding within a naturalistic self-conception. This summation is followed by a brief epilogue reflecting upon one especially important way in which this naturalistic account of ourselves and our scientific achievements and projects makes a difference to our self-understanding. A naturalistic account of language and science as forms of niche construction highlights (p.35) the particularity, contingency, and vulnerability of conceptual understanding as part of the natural history of our species. It does so in a way that not merely accounts for the normative authority of scientific understanding, however, but recognizes the sciences’ centrality to our way of life and our current political, cultural, and environmental situation and prospects.


(1.) I would argue that Hegel’s criticisms of Kant’s transcendental idealism, Nietzsche’s relentless exposure of residual theological assumptions within putatively naturalistic or “free-thinking” projects, Heidegger’s conception of Dasein as being-in-the-world, and Merleau-Ponty’s reflections upon the bodily basis of intentionality should also serve as important contributions to the articulation of a more adequately naturalistic philosophical standpoint, but their work is only beginning to be assimilated by philosophers who aspire to a naturalistic understanding.

(2.) Some readers might infer from this claim that the issues raised by naturalism are not real or abiding concerns. This inference would be mistaken. That an inquiry bears the marks of its history is no objection to the seriousness of the issues it raises, even if there have been and will be historical shifts in the conception of what those issues are. Moreover, the appeal to a philosophical standpoint outside of our natural history as inquirers, as the standard for which philosophical issues are important, is not one that naturalists should accept. Thanks to Willem deVries for calling attention to this possible objection.

(3.) For a historical discussion of modal logic and modal concepts during the relevant parts of the twentieth century, see Shieh (forthcoming). For a discussion of the philosophical significance of this history from a distinctive point of view, see Brandom (2008, ch. 4).

(4.) The issue of whether there are laws (or “strict laws”) outside the physical sciences still divides many naturalists who agree that scientific understanding has a modal dimension. In chapter 8, I argue that a conception of laws of nature that recognizes their role in scientific practice shows that laws are pervasive even in the life and human sciences. This conception of laws itself draws upon the central Sellarsian theme of attending to the role that various concepts or locutions play in reasoning.

(5.) The distinction between left-and right-Sellarsians tracks two loosely defined groups of philosophers, each strongly influenced by the work of Wilfrid Sellars. Right-Sellarsians (exemplified by Ruth Millikan, Daniel Dennett, Paul Churchland, William Lycan, or Jay Rosenberg) draw especially upon Sellars’s commitment to scientific realism, his thoroughgoing naturalism, his insistence upon accommodating a more sophisticated empiricism and a prominent role for conceptual rationality within a broadly reductionist conception of the scientific image, and in some cases, his retention of a role for representational “picturing.” Left-Sellarsians (exemplified by Richard Rorty, Robert Brandom, John McDowell, or John Haugeland) emphasize his rejection of the empiricist Myth of the Given, the irreducibility of the logical space of reasons to causal or law-governed relations, his emphasis upon inferential roles as determinative of conceptual content, and the role of social practice in interpreting and justifying conceptual content while downplaying or rejecting his naturalism, scientific realism, and pictorial representationalism.

(6.) Brandom, McDowell, and Haugeland each rejects Sellars’s own proposed “fusion” of the manifest and scientific images as dependent upon an untenable distinction between describing what is the case and “rehearsing a [shared] intention” (Sellars 2007, 408). I agree but will not argue for that claim here.

(7.) As I argue in chapter 2, their work in this respect is constructively supplemented by other recent accounts of the role of practical bodily skills in perception and action, building upon Heidegger’s and Merleau-Ponty’s phenomenology. Most of the phenomenological discussions of “skilled coping” with our surroundings have concluded that the importance of unreflective bodily skill in disclosing the world to us challenges the priority that the left-Sellarsian tradition ascribes to conceptual understanding (Dreyfus 1979, 1991, 2005; Kelly 1998, 2001, 2000; Carman 2008; Schear 2013). I argue below that these oppositions are misplaced, and thus that work by Dreyfus, Kelly, Carman, Thompson (2007), or Gallagher (2005) constructively engages with the insights of the left-Sellarsians. Some philosophers, notably Nöe (2004, 2009), Lance (2000), and Haugeland (1998, ch. 9), already proceed in ways that build upon that continuity.

(8.) Epistemologists recognize that knowledge continues to grow and are concerned to recognize and promote that openness to further development. Some epistemologists (empiricists are a prominent example) also recognize limits to scientific knowledge, which therefore constrain future inquiry. Yet even in looking ahead, epistemology characteristically does so in the future perfect tense—that is, from the projected standpoint of one looking back upon the prior achievement and justification of knowledge claims. The standpoint of research has a different temporal orientation in which key concepts, methods, and claims are at issue in ongoing inquiry and provide a more or less determinate direction to inquiry despite, or even because of, their partial indeterminacy and open-endedness.

(9.) An influential example of such an approach received classic formulation in Carnap’s (1950) “Empiricism, Semantics and Ontology.” Carnap distinguished internal questions, which can be expressed with determinate truth values and assessed within a language, from external questionsabout the existence of entities independent of any linguistic framework and distinguished bothkinds of question from the pragmatic issue of which language to adopt.

(10.) Price (2011) rightly emphasizes a functional pluralism within language, which cannot be accounted for in terms of a general account of representation, even though one does need to account for the role of a common assertoric form that can be used in functionally diverse ways. Yet I am also emphasizing a further shift in this direction, from thinking about language as a structure with diverse uses, to discursive practice, which gives philosophical centrality to these patterns of situated use.

(11.) Sometimes, as Godfrey-Smith (2002) notes, the representational structures and processes that supposedly constitute cognition have been taken as embedded in patterns of neurological “wiring-and-connection” (Sterelny 2003, 4); for other theorists, they were instead global explanatory attributions needed to make sense of organisms’ overall patterns of responsiveness to their surroundings, for which Dennett’s (1987) “intentional stance” is an exemplary case. For my purposes, the recent challenges to representationalist accounts of cognition need not differentiate between these two opposing versions of cognitive representationalism.

(12.) A substantial and growing body of philosophical and cognitive-scientific work on “extended” or “enactive” cognition (Clark 2003, 2008; Nöe 2004, 2009; Thompson 2007; Chemero 2009; Rowlands 2010; Shapiro 2011, among others) complements and reinforces many of the themes in my argument. I have not attempted to develop those connections because they are not needed to explicate the primary revisions of philosophical naturalism advanced in the book, even though their work supports or further develop many of my more specific themes.

(13.) Organisms’ perceptual/practical capacities are “selective” in a dual sense. They are directed toward only some features or aspects of their physical surroundings and do not register or respond to others. These relevant aspects of their physical surroundings in turn constitute the organism’s “selective environment” (Brandon 1990; Brandon and Antonovics 1996)—that is, the environmental configuration that is selectively relevant to the organism’s adaptive fitness, both in being relevant to the evolutionary prospects of the reproductive populations to which they belong and as having themselves arisen in response to past selective regimes. The selective environment of an organism or its lineage incorporates those aspects of its environment that differentially affect its physiological functioning and population size, its normal developmental patterns, and its comparative fitness in relation to other organisms and lineages.

(14.) The distinction of extension from intension differentiates the object of an intentional directedness from its manner of presentation (how the object is “taken” to be in that intentional comportment toward it). This provisional formulation suggests that organisms’ constitutive interaction with their environments “picks out” which aspects of their surroundings belong to their environment without thereby having a “sense” or manner of presentation that might incorrectly characterize the very aspect of the world that it picks out. The claim may seem odd, because organisms do respond differently to different aspects of the world: eating some, fleeing others, using still others as concealment. Despite its initial, provisional usefulness, what is ultimately misleading about describing organisms’ way of life as determining the organisms’ selective environment “extensionally” is that in semantic contexts, extensions are understood to consist in sets of objects with multiple determinations. What the organisms’ way of living “picks out” is not an object, however, but what Gibson (1979) calls an “affordance,” defined only in relation to what it “affords” the organism. See chapters 24 for further discussion and clarification.

(15.) One could put the point another way by saying that its normal way of life, as responsive to and dependent upon interconnected features of its surroundings, is a holistic pattern of “taking as.” I prefer instead to distinguish organisms’ “one-dimensional” selective directedness toward what thereby becomes part of their environment from a further two-dimensional articulation and tracking of different ways of conceiving aspects of its environment within the larger pattern of its selective interaction with that environment. This distinction is developed in greater detail throughout part 1.

(16.) The level of “reliability” of reproduction need not match the evolved replicative fidelity of cellular transcription, translation, and expression of DNA sequences, which is itself a dynamic and only partially reliable process. So long as there is sufficient stability to affect the cumulative selective pressures on the organism’s developmental patterns, niche construction can have a significant evolutionary effect, often on more rapid time scales than is possible for evolution that is directly driven by genetic mutations and duplications or regulatory shifts in gene expression.

(17.) Chapters 35 work out how to think about linguistic understanding and conceptual normativity as examples of niche construction and how that matters to a naturalistic conception of our linguistic and conceptual capacities.

(18.) My argument below does not depend upon whether our various expressive repertoires evolved together or if one of them arose earlier in ways that enabled others.

(19.) We cannot easily isolate the role of discursive niche construction from other physiological and cognitive changes that were involved in enabling and sustaining it. The long history of coevolution of language and Homo sapiens has enhanced and reconfigured our perceptual and cognitive capacities, from the structure of the human brain and its interconnectedness with various sensory and motor capacities (such as our refined capacities for voluntary vocal articulation and auditory discrimination and diminished olfactory sensitivity), to our highly neotenous bodily and neurological development with its associated forms of extended child-rearing, and the relative stability of social groups from the familial to the linguistic.

(20.) Bolker (1995) offers the telling example of the standard model organisms for developmental biology, whose common features of rapid, highly canalized development, short generation times, small adult size, and single-stage developmental process effectively isolate “development” from environmental interaction and block the factors that govern developmental canalization from experimental scrutiny within this scientific domain.

(21.) A growing literature in the anthropology of science and in cyborg anthropology has been especially attentive to how scientific work is situated within broader cultural patterns of conceptualization and significance. Prominent anthologies in this field include Downey and Dumit (1997); Layne (1998); Goodman, Heath, and Lindee (2003); and Franklin and Lock (2003). Relevant monographs include Haraway (1997), Rabinow (1996), Traweek (1988), Dumit (2004), Helmreich (1998, 2009), and Martin (1994, 2007), among many others.

(22.) Lange’s understanding of laws does not reject the connection of laws with necessity but instead treats nomological necessity as a holistic stability of the truth of laws under various counterfactual suppositions and inductive extensions. The result is to understand nomological necessity as expressing a norm of reasoning in scientific practice rather than a special kind of truth independent of the practical contexts within which the laws are used. In this approach to laws, counterfactuals, and nomological necessity, which gives priority to their role in scientific reasoning, Lange builds upon a central theme in Sellars’s own thinking about conceptual understanding. See especially Sellars (1948, 1957). I discuss laws and modalities more extensively in chapter 8.

(23.) In this emphasis upon doing justice to both the disunity of the various scientific disciplines and other specialties and their mutual accountability, my argument develops a central theme from Sellars’s own account of the scientific image (2007, 370–71). Thanks to Willem deVries for reminding me of this important continuity with Sellars.

(24.) It may seem odd initially to think of metaphorical uses of theoretical concepts as material transformations akin to the building of experimental systems or new theoretical models. Yet Davidson (1984) and his followers (especially Rorty 1991) and Bono (1990) have each in different ways emphasized that metaphor is a phenomenon of the use of language in which a nonstandard use is an “unfamiliar noise” (Rorty 1991) or a material exchange between discourses (Bono 1990). Once we understand language itself as a form of behavioral niche construction, all linguistic uses have to be understood as material components of our developmental and selective environment.

(25.) Philosophers of language often do appeal to causal interaction with the world as the basis for understanding linguistic reference. Yet it is difficult to articulate both reference and conceptual content via the same causal entanglements so as to differentiate what we are talking about from how we take it to be. The conceptual content of theoretical understanding is often thereby taken to be entirely intralinguistic, thereby implicitly expressing an “immaculate” conception of the world from the outside. See especially chapter 7. (p.36)