Introduction

I take up this topic with some trepidation, for these are often troubled waters. But 'tis oil I mean to spread, and calm I hope to restore. The occasion, of course, is the 1999 decision, by the State School Board for Kansas, to delete the topic of Darwinian evolution from the required curriculum for high school biology, and the topic of big bang cosmology from the required curriculum for high school physics. This dual deletion was itself a gentler event than it might have been, for the worthy group who comprised the school board wisely made no attempt to prohibit the teaching of either topic in the high schools of Kansas. Instead, it permanently removed these two topics from the examinations that Kansas students are required to write, and pass, to get credit for their courses in biology and physics.

This removal has substantial consequences of its own, to be sure, consequences of which the board was entirely aware. As measured against the narrow goal of getting a decent grade in either of these new “Kansas Science” courses, a student now has no motive (indeed, given finite resources, has a negative motive) to learn the substance of either of the disputed topics, and any teacher who presumes to teach them, in the teeth of the new exam policy, is strictly wasting instructional time that could be better spent elsewhere. This, I believe all parties will calmly agree, was the central point of the board's decision.

Professor Andy Clark's splendid essay represents a step forward from which there should be no retreat. Our de facto moral cognition involves a complex and evolving interplay between, on the one hand, the nondiscursive cognitive mechanisms of the biological brain, and on the other, the often highly discursive extrapersonal “scaffolding” that structures the social world in which our brains are normally situated, a world that has been, to a large extent, created by our own moral and political activity. That interplay extends the reach and elevates the quality of the original nondiscursive cognition, and thus any adequate account of moral cognition must address both of these contributing dimensions. An account that focuses only on brain mechanisms will be missing something vital.

I endorse these claims, so compellingly argued by Clark, for much the same reasons that I also endorse the following claims. Our de facto scientific cognition involves a complex and evolving interplay between, on the one hand, the nondiscursive cognitive mechanisms of the biological brain, and on the other, the often highly discursive extrapersonal “scaffolding” that structures the social-scientific world in which the brains of scientists are normally situated, a technologically and institutionally intricate world that has been, to a large extent, created by our own scientific activities. That interplay extends the reach and elevates the quality of the original nondiscursive cognition, and thus any adequate account of scientific cognition must address both of these contributing dimensions.

For those of us who were undergraduates in the 1960s, functionalism in the philosophy of mind was one of the triumphs of the new analytic philosophy. It was a breath of theoretical fresh air, a framework for conceptual clarity and computational rigor, and a shining manifesto for the possibility of artificial intelligence. Those who had been logical behaviorists rightly embraced it as the natural and more penetrating heir to their own deeply troubled views. Those who had been identity theorists embraced it as a more liberal but still agreeably robust form of scientific materialism. Those many who hoped to account for cognition in broadly computational terms found, in functionalism, a natural philosophical home. Even the dualists who refused to embrace it had to give grudging approval for its strictly antireductionist stance. It had something for everyone. Small wonder that it became, and has largely remained, the dominant position in the philosophy of mind, and, perhaps more importantly, in cognitive psychology and classical AI research as well.

Whether it still deserves that position – indeed, whether it ever did – is the principal subject of this essay. The legacy of functionalism, now visible to everyone after forty years of philosophical and scientific research, has not been entirely positive. But let us postpone criticism for a moment, and remind ourselves of the central claims that captured so many imaginations.

The Classical Approach: Its Historical Background

Alan Turing wanted to know, as we all want to know, what conscious intelligence is. An obvious place to start one's inquiry is the presumptive and prototypical instance of the target phenomenon – normal humans – and the endlessly clever and appropriate behaviors they display in response to the endlessly various perceptual circumstances they encounter.

Introduction to the Problem

At least since Locke, color scientists and philosophers have been inclined to deny any objective reality to the familiar ontology of perceivable colors, on grounds that physical science has revealed to us that material objects have no qualitative features at their surfaces that genuinely resemble the qualitative features of our subjective color experiences. Objective colors are therefore dismissed as being, at most, “a power in an object to produce in us an experience with a certain qualitative character.”

Introduction

These are the early days of what I hope will be a long and fruitful intellectual tradition, a tradition fueled by the systematic interaction and mutual information of cognitive neurobiology on the one hand and moral theory on the other. More specifically, it is the traditional subarea we call metaethics, including moral epistemology and moral psychology, that will be most dramatically informed by the unfolding developments in cognitive neurobiology. And it is metaethics again that will exert a reciprocal influence on future neurobiological research – more specifically, into the nature of moral perception, the nature of practical and social reasoning, and the development and occasional corruption of moral character.

This last point about reciprocity highlights a further point. What we are contemplating here is no imperialistic takeover of the moral by the neural. Rather, we should anticipate a mutual flowering of both our high-level conceptions in the domain of moral knowledge and our lower-level conceptions in the domain of normal and pathological neurology. For each level has much to teach the other, as this essay will try to show.

Nor need we resist this interaction of distinct traditions on grounds that it threatens to deduce normative conclusions from purely factual premises, for it threatens no such thing. To see this clearly, consider the following parallel. Cognitive neurobiology is also in the process of throwing major illumination on the philosophy of science – by way of revealing the several forms of neural representation that underlie scientific cognition, and the several forms of neural activity that underlie learning and conceptual change (see, e.g., Churchland 1989a, chapts. 9–11).

The physical brain, of both humans and animals, has begun to give up its secrets. Those secrets have been locked away in a bony vault, encrypted in a microscopic matrix of 100 billion neurons and 100 trillion synaptic connections, for the entire history of our philosophical musings, with no more influence on the content of those musings than the influence exerted by the equally hidden secrets of the kidney, or the secrets of the pancreas. The winding path of our philosophical theorizing has been steered by other factors entirely. Those factors have been many and various, even glorious, and they have been precious for existing at all. But they have not included even the feeblest conception of how the biological brain embodies information about the world, or of how it processes that information so as to steer its biological body through a complex physical and social environment. In these dimensions, we have been flying blind for at least three millennia.

But our blinders here have begun to be lifted, and our ignorance has begun to recede. A new generation of techniques and machines of observation has given us eyes to see into the encrypted details of neuronal activity. A new generation of scientists has given us a self-critical community of determined empirical researchers. And a new generation of theories has given us at least an opening grip on how the brain's massive but microscopic matrix might perform the breathtaking feats of real-time cognition that so compel our philosophical attention.

One of the robustly bright spots in Professor Alvin Goldman's philosophical vision has been his determination to explain why some specific cognitive representations should and do count as knowledge, in terms of the background reliability of whatever cognitive mechanisms or procedures actually produced those representations on the occasion in question. Beyond giving us some welcome and plausible relief from Gettier-type counterexamples to the original justified-true-belief accounts of knowledge, Goldman's vision here naturally directs our theoretical attention toward the mechanisms that, in living terrestrial creatures, actually give rise to our cognitive representations, and toward the profile of epistemic virtues and vices that those mechanisms may display.

These mechanisms of representation-fixation, and the character of the various representations to which they give rise, are the focus of this essay. But my purpose goes beyond merely plumbing the neural- or implementation-level hardware that serves to execute the molar-level cognitive activities as described by Goldman. In particular, it is not my aim to provide a neural-level account of the fixation of belief, for example, or an account of the fixation of any other propositional attitude, for that matter. For what motivates me here is the growing body of evidence that the overwhelming preponderance of human knowledge has nothing whatever to do with anything remotely like the propositional attitudes.

Twenty years of research in the several neurosciences, I shall argue later, indicates that the various forms of cognitive representation that dominate, and perhaps even exhaust, human cognition are not the classical propositional attitudes at all.