Ah I&m m Pyyrhol. Vol. 12. No. 3, pp. 329-329 1994 Elsevier Science Ltd

Printed in Great Britain 0732-I lRX/94 $7.00

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NATURALISTIC VS. NORMATIVk EPISTEMOLOGY*

RICHARD F. KITCHENER Department of Philosophy, Colorado State University, Ft. Collins, CO 80523, U.S.A.

This is a monumental work in several ways. First, it forges a new path in interdisciplinary scholarship containing important discussions of the connection between the history of modern epistemology and the history of psychology. Hatfield’s scholarship in all these areas is first-rate and will set new standards for future scholars. Secondly, this is one of the few books devoted to a historical discussion of the issues underlying the very possibility of the burgeoning area of naturalistic epistemology (Kornblith, 1992).

Hatfield’s main concern is with the controversy concerning naturalistic vs. normative epistemologies (in particular theories of spatial perception) and indirectly the relations between psychology and philosophy. He traces this controversy (roughly) from the seventeenth century to the turn of the present century. In the process, he discusses (and contrasts) the normative epistemologies of Aristotle, Descartes, Locke and Kant with the naturalistic epistemologies of Hume, Hartley and Helmholtz. But more than this, he fills in this larger historical picture with detailed discussion of minor figures including Wolff, Tetens, Fries, Herbart, Steinbuch, Tourtual, Miiller, and Lotze (among others). This is an intellectual feast both for philosophers and psychologists with the bill of fare including discussions of the normative vs. the natural, the psychological vs. the epistemological, nativism vs. empirism, and rationalism vs. empiricism, all played out against the historical backdrop of modern philosophy and science. There is something here for everyone and everyone will find something to their liking.

An introductory chapter lays out the philosophical issues separating normative and naturalistic epistemologies and rationalism vs. empiricism, and the related epistemological issues of nativism vs. empiricism regarding the perception of space. From this rich discussion, Hatfield concludes it is a mistake to think that Kant was a simple nativist about space perception.

Hatfield proceeds (in Chapter 2) to a historical overview of the views of Descartes, Locke, Hume on space perception. Chapter 3 treats us to a discussion of Kant’s views on these same issues. Hatfield’s discussion of the intricate relations between Kant’s transcendental philosophy, transcendental psychology and empirical psychology is first-rate.

Chapter 4 concerns the historical reaction to Kant and contains discussion of

*Critical review of Gary Hatfield (1990) The natural and the normative: thtwies of spatial perceptionfrom Kant to Helmholtz (p. xii + 343). Cambridge, MA: MIT Press. $35.

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324 R. F. !Sitchenel

Fries, Herbart, Steinbuch, Tourtual and Lotze. It is especially Hatfield’s discussion of Steinbuch and Tourtual that is interesting and important since virtually nothing has been written on these figures. Together with several others, they formed a kind of pre-Darwinian naturalistic teleology (stressing the “functional organization” of biological life) (see also Lenoir, 1982). Chapter 5 is largely devoted to Helmholtz’s views on the epistemology and psychology of spatial perception and contains a fine discussion of the question of whether (and in what sense) Helmholtz’s empiricism answered “Kant’s nativism”. Chapters 6 and 7 are general discussions-a general summary and a conclusion-followed by two very interesting Appendices.

What is clearly the central theme of the book is the issue between naturalistic and normative approaches to space perception (in particular) and to epistemology (in general). Hatfield spends considerable time discussing these (and related philosophical issues) and moves discussion onto a new and higher plane. But it is his characterization of these issues that strikes me as in need of further clarification, for on this issues hang the questions of whether Locke really lv;Is a normative epistemologist, whether Kant’s transcendental psychology makes any sense, whether contemporary cognitive psychology is naturalistic or normative, and whether the current program of naturalistic epistemology is even possible.

Hatfield contrasts metaphysical vs. methodological approaches to the normative-naturalistic dispute, producing four possibilities. (1) M&zphysical naturalism is the view that mind is reducible to matter; here belong the ontological reductionists and eliminantivists Hobbes, de la Mettrie, Holbach and Priestley. (2) Metaphysictll normntivisk is the contrary claim that “the mind is essentially normative in its essence, that it is the nature of the mind to discover the truth, to make valid inferences, to judge correctly” (p. 17). Historically, this view has been associated with the claim that the mind is outside of nature and (perhaps) made of a non- natural substance (e.g. Descartes). (3) Methodological naturalism is the view that the mind can be completely understood using the methods and modes of explanation of the natural sciences, namely physics (pp. 16, 17). Here belong Hume and Helmholtz. (4) Methodological normatiuism is the denial of methodological naturalism; thought is essentiallyjudgmental in nature and tied to (irreducible) normative standards; “thought must be investigated ‘philosophically’ through the analyses, interpretation, and criticism of our cognitive practices and of the concepts through which we describe such practices” (p. 18). Here, distinctively philosophical methods are necessary associated with the names of Descartes, Kant, Husserl, Ryle, etc.

Hatfield (rightly in my view) claims that historically the most important issue was over methodological normativism vs. methodological naturalism. But is it precisely Hatfield’s discussion of this issue that needs more attention. What, in particular, is methodological naturalism? What is to be included as a “method of science” and a “scientific explanation”? Hatfield argues (p. 28) that a method of science can’t be merely empirical (e.g. experiential or introspective) since one can have a genuine normative epistemology based upon empirical obsemation (e.g. Locke tried to establish a normative epistemology by describing our mental life via observation/introspection). But why then why shouldn’t Locke’s approach be called “naturalistic”? Clearly, if one were to argue that special non-natural methods

Naturalistic vs. normative epistemology 325

are necessary, such an approach would be non-naturalistic, but this is not the case with Locke. In short, if empirical observation is not to count as employing the scientific method, what then does?

What about scientific modes of explanation ? Again, more discussion of this question is called for. Hatfield suggests that (historically at least) the only legitimate explanation known by modern individuals was a mechanistic one patterned after Newtonian mechanics (e.g. psychological associationism). What does such a Newtonian mechanistic explanation involve, and is naturalism committed to it? Hatfield points out (pp. 28, 75, 239) that there were genuine normative epistemologists (Wolff, Tetens, Eberhard) who attempted to construct a Newtonian model of the knowing mind but ones where the basic “atoms” were characterized in normative terms (e.g. as “ideas” or “concepts”). Similarly, there were individuals who believed in normative laws of the mind but (again) these laws were described non-naturalistically, in non-assocationistic terms as, e.g. analogous to “laws of logic”. Likewise (p. 239), a belief in mental causality is not sufficient for naturalism (since, according to Hatfield, Descartes and Wolff both believed in such mental causality). Hence a commitment to Newtonian physics, determinism, or causality tout court is not a sufficient condition for a naturalistic account.

However, neither are these things apparently necessary, since, as Hatfield’s discussion of German naturalistic teleology points out, there were several methodological naturalists (e.g. Steinbuch, Tourtual) who did not employ a Newtonian mode of explanation.

It turns out, that (according to Hatfield) a methodological naturalism must be an eliminativism or a reductionism, an account in which no irreducible normative concepts appear: “the naturalist must reduce the activities of the mind to processes that do not include irreducibly rational or judgemental operations” (p. 25). Hence a methodological naturalist is one who believes an appropriate description and explanation of the epistemic activities of the mind must contain no irreducible normative concepts. A methodological normativist can believe in determinism, causality (and even model one’s approach after Newtonian mechanics) as long as one’s basic concepts are described and characterized in irreducible normative terms, e.g. ideas, concepts, beliefs and judgments. We can call this concept

reductionism: all normative concepts can be logically reduced to non-normative ones. But concept reductionism isjust a semantic version of metaphysical naturalism, the kind of physicalism and “unity of science” championed in an earlier era by Carnap (1938, 1963) and Feigl (1963). It thus appears that methodological naturalism is not that different from metaphysical naturalism after all. Of course, it is possible (as Hatfield suggests) to believe that normative concepts must be reducible to non-normative ones (e.g. the association of sensations) without believing the latter are physical, but some version of concept reductionism is necessary nonetheless. This would give us two versions of concept reductionism:

Weak Concept Reductionism (WCR), all normative concepts are reducible to non-normative ones. Strong Concept Reductionism (SCR), all normative concepts are reducible to physical concepts.

326 R. F. Kitchenel

But how should we characterize “non-normative” and “physical.” We can distinguish two versions of SCR (Carnap, 1963; Feigl, 1963) :

Strong Concept Reductionism, (SCR,), all normative concepts are reducible to concepts employing only a space-time language. Strong Concept Redurtionisrnj (SC/L), all normative concepts are reducible to concepts adequate for describing the inorganic realm.

Clearly, both versions of SCR are semantic versions of metaphysical naturalism (Hellman & Thompson, 19’75). 0 ne could be a SCR, and a methodological naturalist but one could be SCR, and a methodological naturalist; indeed, something like SCR, was maintained by those advocating a strong unity of science perspective, namely there is just one method for all the sciences-a method of intersubjective testability (Feigl, 1963). But does such a requirement mean that normative concepts are to be reduced or eliminated at all? Can one believe, as naturalists do, in the unity of scientific method and reject both versions of concept reductionism (CR)? Clearly, SCR, must be ruled out (Dewey, 1944, p. 2) but what about SCR,? Scientific method is committed to exfwrimental obseruation (Dewey, 1944, p. 3)) but what the latter involves is unclear. Must it involve intersubjectivity and a world of public objects? Even Carnap (1963) and Feigl (1963) admitted introspective knowledge into their physicalism and unity of science program, with Carnap claiming that intersubjective confirmation was perhaps too strong a condition to impose.

A naturalist surely believes mind is a part of nature-a metaphysical claim. But the question is: what does nature include? Must it include-just the inorganic, or can it also include something else? As naturalists have argued (Dewey, 1944; Dewey & Nagel, 1945; Randall, 1944) naturalists need not be materialists, but neither need they be SCR,s.

As recent discussions of the concept of qhwniencu (Kim, 1990) have suggested, one can maintain there are normative properties in nature but that they supervene on a physicalistic base. Epistemic supervenience can then be (roughly) formulated as:

f$hi.pi.rtrmic SupPrvrnirnrr, a set of normative properties N is supervenient on a set of physical properties P,just in case, necessarily, any object with property N will also have property P.

Normative properties thus depend upon physicalistic properties, but there is no reason to insist such normative properties be eliminated or reduced. Indeed, part of the attraction of the supervenience thesis is precisely the fact that it is not reductionistic. Presumably, therefore, one can experience (in some sense) these normative properties as a result of experiencing the physicalistic base, or one can know (be justified in believing) something has a normative property (even if one cannot experience it) by virtue of its physicalistic base. [This is what Strawson (1985) would call a scft naturulism since everything is natural but nature includes more than the material.]

If the thesis of normative (epistemic) supervenience is defensible, this would provide a third kind of metaphysical view in which the mind is essentially normative

Naturalistic vs. nonnative epistemology 327

in its operations but is not outside of nature; on this view norms (in some sense) are

in nature. Coupled with this would be the rejection of methodological normativism and its

alleged philosophical methods; a naturalist must believe the only appropriate methods are natural ones. But once again what are naturalistic methods? If observation (or introspection) were naturalistic, this would (contra Hatfield) be sufficient to turn Locke into a methodological naturalist. (This is as it should be since Locke was not a SCR.) But one can deny CR and still be a methodological naturalist. Indeed, Locke provides a good example of an individual who can be interpreted as holding something like the thesis of epistemic supervenience, for something has an epistemic property for Locke only if it has a naturalistic property [e.g. one involving a psychogenetic property-a point Hatfield himself seems to make (pp. 29-30, 273)].

Thought, on the present view, can be essentially judgmental, described in normative terms, tied to normative standards and yet studied by scientific methods and explained by ordinary scientific modes. I have already suggested that scientific explanation need not involve concept reductionism (as current cognitive science shows).

Hatfield’s discussion of the natural vs. the normative has implications for current cognitive psychology, since it raises the question of whether it can be methodologically naturalistic, and if so, whether it need be concept reductionistic.

We owe it to Hatfield to have shown (historically) that there was a psychology that was not naturalistic and not necessarily empirical, for several individuals were concerned with constructing what we can call a normativepsychology, an investigation into the epistemic powers of the mind. Following Aristotle, this could be called a noetic psychology, and it would be non-naturalistic in its methods (employing, e.g. methods of intuition, transcendentalism); perhaps it would be metaphysically normative (e.g. involving an immaterial soul, a noumenal realm, etc.). On such a neotic conception, psychology would be markedly different from naturalistic psychology. Although both types of psychology might be empirical (in some sufficiently broad sense of that term), a naturalistic psychology would have to be concept reductionistic according to Hatfield, whereas a noetic psychology would not.

A noetic psychology would be relevant to e$stemology whereas a naturalistic psychology would not be. If this is correct, then we must re-evaluate the issue of psychologismand the relation between psychology and epistemology. For at the very least, it would not be true that psychology (iiberhaupt) is radically separate from epistemology. For those who have pressed the point that psychology and epistemology are radically distinct (Hamlyn, 1957; Ryle, 1949)) this must be reinterpreted as claiming that naturalistic psychology is radically separatefrom epistemology. These same individuals might be prepared to allow that a noetic psychology is relevant to epistemology but only if it were non-empirical and employed distinctively philosophical methods. (This would apparently be close to what eighteenth century philosophers understood a rational psychology to be.) Once again the issue would be over the relevance of an empirical method in adjudicating epistemic issues. This shows, once more, that Hatfield’s characterization of these issues needs more discussion.

328 R. F. Kitchener

I have been suggesting that there are two versions of naturalistic psychology, with the reductionistic version being irrelevant to epistemology; a non-reductionistic one, on the other hand, purports to hold out the promise of being relevant to epistemology, e.g. by virtue of the thesis of epistemic supervenience. Here psychological properties are epistemically relevant to determine whether, say, a belief is warranted because certain psychological properties provide the naturalistic base upon which epistemic properties supervene. If so, then empirical, psychological facts are relevant to normative evaluation since (in some sense) they determine it or are necessary for it. However, it would not show the empirical science of psychology to be relevant to epistemology (unless psychology were involved in disclosing such psychological facts). A stronger position for psychology would involve the more controversial claim that these supervenient principles themselves belong to the domain of psychology (or that psychology is relevant to establishing such supervenient principles). This is the thesis of meta-epistemic

supevvenience.

All of this has important implications for contemporary psychology in general and cognitive psychology in particular. Hatfield’s book vividly raises the question: what is the nature of (cognitive) psychology? Is it a naturalistic? Empirical? Concept- reductionist? Given Hatfield’s historical framework, one could argue that cognitive psychology is a version of non-naturalistic (noetic) psychology, e.g. a kind of transcendental psychology (see Kitcher, 1990, for a similar argument). Such a transcendental psychology might be defined (as Hatfield does) as “the psychology of the Knozuingmind, of the mind that makes objectivelyvalidjudgments” (p. 86).* Presumably, such a transcendental psychology might be empirical but not naturalistic (although the latter possibility seems unlikely) .+

However, contemporary cognitive psychology might be a naturalistic psychology. Which kind of naturalistic psychology? Could there be, e.g. a non-reductionistic naturalistic cognitive psychology? Most contemporary cognitive scientists (e.g. Johnson-Laird, 1988; Newell, 1990) would seem to believe so, but apparently Hatfield does not (cf. pp. 267470).

Even though I believe Hatfield is wrong on several points (for the reasons I have given), he has raised several issues crucial to the program of a naturalistic epistemology and cognitive psychology. The present work ought to become standard reading in the philosophy of psychology and in epistemology for some time to come.

REFERENCES

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*I have argued (Kitchener, 1986, forthcoming) that this is very close to what Jean Piaget’s genetic epistemolob7 is all about. *Onr might argue that current non-cognitive psychology (e.g. social psychology, developmental psychology) is non-naturalistic (and non-empirical) because it is concerned with hermeneutics. with the issue of how to interpret behavio-a cultural concept tied to historical traditions.

Naturalistic vs. normative epistemology 329

Carnap, R. (1963). Replies and systematic expositions. In P. A. Schilpp (Ed.), The philosophy of Rudolph Curnap (pp. 859-l 016). LaSalle, Illinois: Open Court.

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