Three
Confusion about Common Sense

Another factor that has made the mind-body problem seem so intractable is confusion about common sense. Philosophers as well as scientists have failed to distinguish between the kind of common sense that science can sensibly reject and the kind that it cannot.

Science has widely come to be understood as a systematic assault on common sense. Common sense said the world was flat; science showed this to be false. Common sense said the sun and the moon were the same size; science showed this to be wrong. Common sense said the Earth was the center of the universe; science showed this to be false. Common sense said matter was solid; science has shown this to be false. And so on. Progress in understanding has come to be seen as the accommodation of common sense to the scientific worldview. As modern philosophers and scientists have dealt with the mind-body relation, accordingly, they have assumed that the same adjustment would occur. As Searle puts it, "the general form of the mind-body problem has been the problem of accommodating our common-sense and prescientific beliefs about the mind to our general scientific conception of reality" (MBWP, 215).

As the above litany of examples illustrates, furthermore, science is seen as successively revealing truths that in area after area show the illusory nature of common sense. Through this portrayal, common sense has come to be regarded as generally mistaken. Through this way of understanding the relation between science and common sense, the fact that a given scientific theory runs counter to our "commonsense intuitions" can be complacently dismissed. In fact, as Searle points out, this discrepancy with commonsense intuitions can be regarded as a point in the theory's favor:

The fact that the views in question are implausible and counterintuitive does not count against them. On the contrary, it can even seem a great merit of contemporary functionalism and artificial intelligence that they run dead counter to our intuitions. For is this not the very feature that makes the physical sciences so dazzling? Our ordinary intuitions about . . . the solidity of the table . . . have been shown to be mere illusions. . . . Could not a great break-through in the study of the mind similarly show that our most firmly held beliefs about our mental states are equally illusory? Can we not reasonably expect great discoveries that will overthrow our commonsense assumptions? (RM, 17–18)

Searle's criticism of this attitude, his contention that an adequate theory cannot deny "obvious" truths (RM, xi, 1, 3, 5), and his employment of "commonsense objections" to identism and eliminative materialism (RM, 39, 48) imply a distinction between two quite different meanings of "common sense," which can provisionally be called the weak and the strong meanings. The idea that not all things called "common sense" are analogous is implicit in Searle's criticism of what he calls the "heroic-age-of-science maneuver" of some eliminative materialists: "They claim that giving up the belief that we have beliefs is analogous to giving up the belief in a flat earth or sunsets" (RM, 48). However, Searle does not, to my knowledge, provide a criterion for distinguishing between the weak and the strong meanings of "common sense" and thereby between things that merely seem obvious to some people and things that really are obvious in the not-to-be-denied sense. This kind of criterion is also implicitly called for by Nagel's principle that, "given a knockdown argument for an intuitively unacceptable conclusion, one should assume there is probably something wrong with the argument" (MQ, x). The problem is that "intuitions" notoriously differ. Is there some criterion for distinguishing between those "commonsense intuitions" that are defeasible by a knockdown argument and those that are not?

The conviction that there is such a criterion lay at the root of the "Scottish commonsense tradition" associated primarily with Thomas Reid.^[1] The criterion for what is common sense in the strong sense was formulated in various ways, but the basic idea was that there are certain notions that are "common" in the sense of universal—truly common to all people—and that they are such because they cannot be consistently denied: The very act of denying them verbally would involve an implicit affirmation. To deny such beliefs, Reid said, would be "metaphysical lunacy."^[2] I have come to refer to common sense in this strong sense as "hard-core common sense,"^[3] to distinguish it from common sense in the weak sense, which I call "softcore common sense." Common sense of the latter sort does not refer to truly common or universal notions but merely to parochial notions that can be denied without pain of implicit inconsistency. In any case, this tradition fell into disrepute and virtual oblivion in the late nineteenth century. One

reason seems to be that proponents came to claim the status of common sense in the strong sense for all sorts of ideas, including reactionary (such as antievolutionary) ones, that did not really match the criterion, a tendency not altogether absent in Reid himself. Another problem was that no naturalistic explanation for the origin of these commonsense notions was offered.^[*] They were, instead, said to have resulted from a supernatural implantation in our souls.^[4] With the demise of supernaturalism, accordingly, no explanation of these commonsense notions seemed possible.

The notion of common sense that is not truly deniable teemerged in twentieth-century philosophy. The best-known version of common sensism has probably been that of G. E. Moore; but his version fails to provide a clear criterion for distinguishing between weak and strong meanings of common sense. Better is the "critical common-sensism" of Charles Peirce.^[5] But the best version, in my view, is that of Alfred North Whitehead. That Whitehead is a "commonsense" philosopher has not been widely recognized, however, for two reasons (besides the fact that most philosophers today simply do not bother to read Whitehead, probably in large part because they were not introduced to him by their own teachers during the rabidly antimetaphysical period of twentieth-century philosophy). One reason is that he used "common sense" in both the weak and the strong senses but failed to point this out. Second, those passages in which the criterion for hard-core common sense is stated do not themselves contain the term "common sense." However, by reading Whitehead with this issue in mind, one can ferret out his doctrine without great difficulty. One can also see that this issue is no merely minor theme in his philosophy but that be understands the very task of philosophy to be that of showing how the various hard-core commonsense notions are mutually consistent. A central task of epistemology, furthermore, is to provide a naturalistic explanation as to why we all share these notions.

Whitehead's clearest statement of the criterion for hard-core common sense is contained in a statement of what he calls "the metaphysical rule of evidence," namely, "that we must bow to those presumptions which, in despite of criticism, we still employ for the regulation of our lives" (PR, 151). Even this statement is not as clear as it might be. One question is who the "we" indicates: all human beings (perhaps all rational beings), or only a limited portion thereof, such as modern Western human beings? I interpret it to mean the former. And when Whitehead says that even if we criticize these notions, we still employ them for the regulation of our lives, does he mean that we inevitably do so, so that we could not do otherwise, or only that it is a contingent fact that all people thus far have done so (which would

[*] Reid spoke of these common notions as "those things, which all mankind have believed without being able to give a reason for it" (IHM, 12).

leave open the possibility that we could quit doing so, perhaps through sustained self-discipline or through adopting a worldview and self-understanding radically different from anything in the past)? Again, I take him to mean the former. Accordingly, I take his meaning to be that the ultimate criteria for theoretical thought are those notions that all human beings inevitably presuppose in practice, even if and when they deny them verbally . This interpretation is consistent with another explicit statement: "[Philosophy's] ultimate appeal is to the general consciousness of what in practice we experience. Whatever thread of presupposition characterizes social expression throughout the various epochs of rational society must find its place in philosophic theory" (PR, 17).

The idea that the notions in question are presupposed in practice is crucial. The contention that these notions are universal cannot be refuted simply by pointing to the fact that some people have verbally denied them. As the first quotation above indicated, Whitehead is speaking of notions that we continue to use in practice "in despite of criticism." The term "practice," in fact, is used in reference to Hume (PR, 81, 133, 242f.), who, denying that we have any direct experience of "causal efficacy" and of an "external world," said that these notions can have no place in our (philosophical or scientific) theory while adding that we must, nonetheless, presuppose them in practice. Against this antirationalism (PR, 153), Whitehead says,

Whatever is found in 'practice' must lie within the scope of the metaphysical description. When the description fails to include the 'practice,' the metaphysics is inadequate and requires revision. There can be no appeal to practice to supplement metaphysics. (PR, 13)

On the basis of these explicit formulations of the idea of hard-core common sense, in which the term "common sense" is unfortunately not used, we can locate many passages in which Whitehead does use the term with this meaning. He speaks of several notions that cannot "be dropped without doing violence to common sense" (PR, 128). He speaks of his "endeavor to interpret experience in accordance with the overpowering deliverances of common sense" (PR, 50) or, in a Searle-like statement, of "the obvious deliverances of common sense" (PR, 51). He speaks, for example, of the direct experience of actual entities beyond ourselves as a "a presupposition of all common sense" (PR, 52).

Whitehead can also, however, use "common sense" in the weaker sense (unfortunately, without a qualifier such as "soft-core" to warn the reader of the very different meaning). For example, he speaks of "the benumbing repression of common sense" (PR, 9). In a statement in Science and the Modern World in praise of then-recent developments in science, especially relativity and quantum physics, he says that "scientific theory is outrunning common sense" (SMW, 114). Elsewhere he says, "It is the part of the special

sciences to modify common sense" (PR, 17). Indeed, he can even speak of "the general common-sense notion of the universe" that he seeks to modify (MT, 129). In these passages, Whitehead is using "common sense" in a nontechnical sense. For example, after saying that science is "outrtmning common sense," he explains his meaning: "The settlement as inherited by the eighteenth century was a triumph of organized common sense. . . . It grounded itself upon what every plain man could see with his own eyes, or with a microscope of moderate power. It measured the obvious things to be measured, and it generalized the obvious things to be generalized" (SMW, 114).

Once we have seen the distinction in principle between soft-core and hard-core common sense, we can agree wholeheartedly that science not only has falsified common sense of the first type in the past but also will probably continue to do so. We will not, however, conclude from this fact that science should lead us to doubt commonsense ideas of the second type, because they are presupposed by the practice of science itself. This kind of common sense provides the "ultimate appeal" to which all theory, including scientific theory, must "bow."

Whitehead has thereby provided, I suggest, the kind of criterion Searle needs to distinguish the "obvious facts" that cannot be overridden by scientific theory from those that can. Whitehead, in fact, formulated his "metaphysical rule of evidence" cited above in response to those who, having "arrogated to themselves the title of 'cmpiricists,' have been chiefly employed in explaining away the obvious facts of experience" (PR, 145). The truly "obvious facts of experience," I suggest, are those that we inevitably presuppose in practice, even if we deny them verbally. One can see, indeed, that eliminative materialists verbally deny a range of notions that Searle rightly regards as obvious. Not having formulated this criterion of obviousness, however, Searle sometimes mixes things that fit it with things that do not. To illustrate: Searle speaks both of "the obvious facts of physics—for example, that the world is made up entirely of physical particles in fields of force," and of "obvious facts about the mental, such as that we all really do have subjective conscious mental states" (RM, 3), as if the truth of these two types of assertions were equally obvious and in the same sort of way. But they are not. The so-called obvious facts of physics, unlike the "obvious facts about the mental," involve a long series of sensory observations and (dubious) inferences. Also, one could deny Searle's statement about the physical world without pain of self-contradiction, whereas this would not (as Descartes pointed out) be possible with regard to the statement about conscious experience.

Yet another qualification is necessary with regard to the term "obvious." I have sought to show how this term could be defined so as to make an appeal to obviousness defensible as an ultimate criterion of philosophical

and scientific acceptability. It is, however, problematic. The word usually is taken (as by my dictionary) to mean "readily apparent." Now, some of our hard-core commonsense notions, such as the fact that we have conscious experience, are readily apparent (some eliminativist arguments notwithstanding), whereas others are less so. For example, it may take some argumentation to convince us, in the face of the great extent to which our behavior is conditioned, that we always presuppose that we have a degree of freedom or, in the face of the evidence for ethical relativism, that we always presuppose the reality of some normative ideals. Given the widespread rejection of both of these beliefs by philosophers and scientists in our time, it would be strange to refer to them as obvious . It is better, accordingly, to speak of the "inevitable presuppositions of our practice" or of our "hardcore common sense."

In any case, these hard-core commonsense notions can be seen to supply the kind of criterion Nagel is presupposing in saying that we should assume that there is probably something wrong with any argument that leads to an "intuitively unacceptable conclusion." Whitehead spells out the criterion of the intuitively unacceptable by speaking of "difficulties which take the shape of negations of what in practice is presupposed" (PR, 13). Without this criterion, Nagel's recommendation could lead philosophers to feel justified in rejecting any good argument for a conclusion they disliked with the flippant assertion, "It contradicts my intuitions." Whitehead countenances no such appeal to idiosyncratic intuitions: "It is a disease of philosophy when it is . . . merely a reflection of the temperamental presuppositions of exceptional personalities" (PR, 17). His appeal is instead to "the general consciousness of what in practice we experience" (PR, 17; emphases added), and he limits the appeal to those notions that all of us inevitably employ in the regulation of our lives (even if we are not conscious of them and even if we explicitly deny them). It is when a theory, whether called philosophic or scientific, contradicts intuitions in this sense that we should assume that something must be amiss.

Using the term "intuitions" for our inevitable presuppositions would be less problematic than speaking of them as "obvious facts." True, this term can be misleading (because it can connote idiosyncratic hunches), but so can the term "common sense," if unqualified. With an adjective such as inevitable, deepest, or universal, the term "intuitions" can serve to refer to these universal presuppositions of practice.

In this relativistic age, of course, many philosophers, even given the above clarifications, will tend to be suspicious of, if not to reject out of hand, the idea that there are any notions or presuppositions that are universal. After realizing that this idea cannot be refuted simply by pointing out that probably every "obvious" idea has been denied by someone —because the claim is about presuppositions of practice, not explicit, verbal beliefs—many will

want to put the burden of proof on those making the positive claim. No universal claim, of course, can be proved by any number of instances. But a universal claim can be disproved by a single negative instance: As William James said, it takes only one white crow to prove that all crows are not black. So the burden is really on those who would deny the universal claim. They need to come up with at least one instance of someone, perhaps themselves, who can live without presupposing the notion in question. And, with regard to one or more of the notions, they may well succeed, especially with regard to some particular formulation of the notion. If we return to a form of commonsensism, we should, with Whitehead as well as Peirce, combine it with fallibilism. The claim that any particular notion is inevitably presupposed in practice is fallible; the attempt to formulate the notion verbally is even more fallible; and even the idea that there are such notions is fallible.

Insofar as claims for such notions survive all attempts to refute them, however, they should be taken as the ultimate criteria for judging a theory's adequacy, and this for a simple reason: If we cannot help presupposing these notions in practice, including the practice of scientific experimentation and theory-building, we are guilty of self-contradiction if our theory denies these notions . And the first rule of reason, including scientific reason, should be that two mutually contradictory propositions cannot both be true.

Is this foundationalism? As usually understood, foundationalism says that nonbasic beliefs are to be derived from basic beliefs and that basic beliefs themselves are not supported by nonbasic beliefs. In my position, however, hard-core commonsense beliefs function not as a foundation upon which all other beliefs are to be built but as a compass telling us when we have gotten off course. And part of the reason why we should have confidence in our hard-core common sense, I argue, is that we can understand in a naturalistic way why we have these beliefs (see pages 27 and 133).

One result of this third snarl in our knotty problem—the failure to distinguish hard-core from soft-core common sense—has been that the former has often been denied in the name of the latter. The idea that the units of the physical world, such as electrons and living cells, are "insentient," in the sense of being wholly devoid of experience of every sort, is one of the most widespread "commonsense" notions of the modern West. It does not, however, belong to our hard-core common sense: It is not universally accepted; it is not inevitably presupposed in practice; one can deny it without necessarily presupposing its truth in the act of denying it. And yet in the name of this parochial, merely soft-core commonsense idea, many modern philosophers and scientists deny other notions, such as freedom and the reality and efficacy of conscious experience, that do belong to our hardcore common sense. The counter-proposal, that soft-core common sense should never be allowed to trump the hard-core variety, brings us to the topic of the next chapter: regulative principles for theory-construction.