1. In their heyday, sense-data theories were the principal exemplars of theories of perception and of first-order knowledge possessing "foundationalist" standing. They dominated the analytic epistemologies of the first half of the twentieth century and have now nearly all disappeared. One reason is that it was discovered that sense data could not be individuated and reidentified except, dependently, by being indexed to the very "material objects" they were meant to replace. See, for instance, Wilfrid Sellars, "Phenomenalism," in Science, Perception and Reality (London: Routledge and Kegan Paul, 1963); also, J. L. Austin, Sense and Sensibilia, reconstructed by G. J. Warnock (Oxford: Clarendon, 1962). Very nearly the only version of the sense-datum (-like) theory still championed among analytic philosophers is that offered by Roderick Chisholm. Chisholm's thesis is an "adverbial" variant, which is to say, it begins with the "self-presenting" states of cognizing subjects, thereby escaping the aporia of the other versions. Nevertheless, it also requires an explanation of the relationship between such states and the real world in order to build (as Chisholm intends) a theory of knowledge of the independent world. Chisholm's may be the last of these theories: much admired for its skill but ultimately too implausible, too remote, too risky a methodological basis for, say, the palpable achievements of the empirical sciences. See Roderick M. Chisholm, Perceiving: A Philosophical Study (Ithaca: Cornell University Press, 1957), and Theory of Knowledge, 2d ed. (Englewood Cliffs: Prentice-Hall, 1977). Sense-data theories of the first sort were very much favored by the Positivists, who had grave difficulties with attempts to ensure their meaningfulness (apart from Neurath's challenge to Protollsätze ). The attempt to find the right formula may be traced through A. J. Ayer's numerous accounts (all failed): for instance, The Problem of Knowledge (Harmondsworth: Penguin Books, 1956), ch. 3. The more methodological difficulties are adumbrated in Carl G. Hempel, "Empiricist Criteria of Cognitive Significance: Problems and Changes" and "Postscript (1964)," in Aspects of Scientific Explanation and Other Essays in the Philosophy of Science (New

York: Free Press, 1965). The general foundationalist theory of knowledge is analyzed in Keith Lehrer, Knowledge (Oxford: Clarendon, 1974). The most famous sense-datum theory is probably that offered by H. H. Price, Perception, 2d ed. rev. (London: Methuen, 1950).

2. Wittgenstein's analysis shows conclusively that Moore's attempt to recover a "Cartesian" source of epistemic certainty was uncompelling. In his remarkably effective way, Wittgenstein subverts the foundationalist presumption of all externalist accounts of knowledge and, at the same time, shows how abandoning foundationalism does not entail skepticism, if only the reliability (not secured criterially—hence, not secured in the Cartesian sense) is grounded in a lebensformlich way. See Wittgenstein, On Certainty . On my reading, the diverse lines of criticism offered by Neurath, Sellars, Austin, and Wittgenstein converge in preparing a ground for a symbiotized account of cognition, but they do not entail any such theory in advance.

3. It is an extraordinary fact that the Positivists believed (at least initially) that the Wittgenstein of the Tractatus was concerned with the empirical foundations of science; whereas the fact is: (a) the Tractatus does not explicitly address empirical sources of knowledge at all; and (b) Wittgenstein meant to exclude all contingent factual claims from his text. His treatment of the problem of the compatibility of colors led him (partly through Frank Ramsey's prompting) to see that he could not satisfactorily draw a demarcation line between contingent and necessary truths regarding colors. He realized, therefore, that the entire project of the Tractatus was placed at risk—perhaps irremediably. See Ludwig Wittgenstein, Tractatus Logico-Philosophicus, rev. ed., trans. D. F. Pears and B. F. McGuiness, corr. (London: Routledge and Kegan Paul, 1972). For their part, the Positivists had hoped Protokollsätze would have functioned as the middle term between Wittgenstein's logical atomism and their own methodology of science. They were mistaken.

4. These notions are bound to sound alien to analytic ears. They do, however, mark the eccentric convergence between Derrida's critique of phenomenology (Husserl) and structuralism (Lévi-Strauss) and the critique I have been mounting against the local forms of privilege in analytic philosophy. Derrida's efforts touch on one or another of the strategies I've called "symbiotized," "post-Kantian," or "poststructuralist.'' Derrida's tactic tends to be reactive and parasitic—and verbally unusual. But the attack on the "originary" is an attack on externalism, and the attack on the "totalized" entails a recognition of the role of internal relations in comparing and assessing conceptual schemes. I don't find the convergence contrived, therefore, or useless. It signifies the possibility of a stronger and more explicit convergence between analytic and continental philosophy. I should say both Derrida's and Wittgenstein's correctives (the latter's, in the Investigations and On Certainty ) draw attention to the insuperability of context: to the pretense of closed conceptual systems and supposed criterial assurances of indubitable truth. What both lack is a clear sense of the historicity of context itself. Wittgenstein's use of the notion of Lebensformen is ultimately more promising (in my opinion) than Derrida's abstract and reactive analyses. Their analyses point beyond themselves to the remarkable (but somewhat muffled) intuition of historicity in Thomas S. Kuhn's The Structure of Scientific

Revolutions, 2d ed. (Chicago: University of Chicago Press, 1970), and the even more remarkable (but unemphatic) prescience of John Dewey's domesticated Hegelianism, for instance in Reconstruction in Philosophy . Both have been largely eclipsed by this time: Kuhn, partly through his own retreat—see, for instance, the Postscript to The Structure of Scientific Revolutions, and also The Essential Tension (Chicago: University of Chicago Press, 1977). Dewey, largely through the selective coopting of pragmatist themes (compatible with externalism) in the American continuation of Russell's and Moore's dismissal of British Hegelianism and the close scanning of the uncongenial themes of American pragmatism, in the work of Quine and Davidson particularly. The result is the almost total eclipse of an interest in historicity in current American analytic philosophy. Continental European philosophy has, for the most part, featured the puzzles of history and social context in Hegelian, Marxist, Nietzschean, phenomenological, existential, hermeneutic, Frankfurt-Critical, and Heideggerean currents. In this sense, Foucault is more promising than either Derrida or Wittgenstein. For purposes of comparison, see Jacques Derrida, "Différance," in Margins of Philosophy, trans. Alan Bass (Chicago: University of Chicago Press, 1982); and Michel Foucault, "Two Lectures," in Power/Knowledge: Selected Interviews and Other Writings 1972-1977, ed. Colin Gordon, trans. Colin Gordon et al. (New York: Pantheon, 1980). A theorem like (5.2), I should add, is the beneficiary of a great many of these converging currents, short of endorsing historicity. But it needs to be said as well that recent European philosophy is (noticeably) also veering away from historicity. I think this is due in no small degree to the growing disenchantment with Marxism and communism evidenced well before the collapse of the Soviet empire and to the perceived confirmation of the triumph of the ahistorical mentality that the Gulf War has come to signify. The result is a palpable conceptual vacuum that, in retrospect, we may conjecture, had been filled by Marxist themes qualifying the principal work of Western thought. In my view, the confirmation appears most saliently among philosophers in Jürgen Habermas's about-face: in his displacing his Marxist and Franfurt-Critical perspective with a (pragmatized) Kantian one. Compare, for instance, Jürgen Habermas, Legitimation Crisis, trans. Thomas McCarthy (Boston: Beacon Press, 1975), with his "Discourse Ethics: Notes on a Program of Philosophical Justification,'' in Moral Consciousness and Communicative Action, trans. Christian Lenhardt and Shierry Weber Nicholsen (Cambridge: MIT Press, 1990). In the United States, the "parallel" but more tepid retreat appears in the self-styled pragmatisms of Putnam and Rorty, who, in rather different ways, have had something to say about their earlier Marxist interests. See, for instance, Richard Rorty, "Trotsky and the Wild Orchids," Common Knowledge 1 (1992). Habermas is conceptually more interesting in this regard, for Habermas is reenacting—post-Hegel and post-Marx—Kant's own inability to surmount his apriorism (along the lines I earlier associated with the preface to the second edition of the Critique of Pure Reason and the letter to Markus Herz that bears on Kant's Copernican revolution). I take that to provide the essential clue to Habermas's own failed Kantianism (as in "Discourse Ethics"). The theme was always present in Habermas, however, as one can we see from the important early essay, "What Is Universal Pragmatics?" in

Communication and the Evolution of Society, trans. Thomas McCarthy (Boston: Beacon Press, 1979). I find Habermas's work to be dominated by the Peirceanized Kantianism of Apel—except, of course, that Habermas disastrously pretends to generate the benefits of apriorism through ("empirical" or "communicative") rational reflection. Compare Karl-Otto Apel, "From Kant to Peirce: The Semiotical Transformation of Transcendental Logic," in Towards a Transformation of Philosophy, trans. Glen Adey and David Frisby (London: Routledge and Kegan Paul, 1980).

5. It is quite extraordinary that Husserl, having grasped the implicit privilege in Kant's "naturalistic" program, "corrects" it by endorsing an even more profound form of "subjective" (or "Cartesian") privilege: partly by disjoining (or at any rate by obscuring the relationship between) the (phenomenologically) ''subjective" and the ("naturalistically") psychological; partly by disjoining (or at any rate by obscuring the relationship between) the "transcendental" powers of the reflective Ego and the culturally enabling resources of whatever reflexive powers human understanding may claim. As far as I can see, Husserl never resolved these puzzles satisfactorily, never fully acknowledged the lebensformlich sources of all our cognizing powers, and never came to terms with the general problem of historicity. In a very real sense, Husserl's philosophy must count as one of the most thoroughgoing violations of theorem (5.2) that modern philosophy affords. See Edmund Husserl, The Crisis of European Sciences and Transcendental Phenomenology, trans. David Carr (Evanston: Northwestern University Press, 1970). It should be borne in mind that Derrida's earliest and most "analytic" work was directly addressed to unmasking the illicit privilege embedded in Husserl's account of geometry. The essay, "The Origin of Geometry," appears in the appendix to the Crisis volume. For Derrida's quite compelling treatment, see Jacques Derrida, Edmund Husserl's Origin of Geometry: An Introduction, trans. John P. Leavey Jr. (New York: Nicolas Hays, 1978). Husserlians have always argued that Derrida was not up to reading Husserl accurately. But the study of the "Geometry" paper dispels the charge. In fact, it exposes Husserl's own uncertainties, even fudging, in a decisive way. (Husserl, one must remember, isolated the process of rational thought from the contingencies of linguistic expression: Derrida locks on to the pretensions of that maneuver with admirable precision.) Resistance to Husserl's failings in this regard has led, in rather different ways, to the divergent programs of Sartre, Merleau-Ponty, and Heidegger. In this respect, late phenomenology has been more critical of Husserl than late analytic philosophy has been of the orienting function of Russell, Moore, and Quine at least. Wittgenstein's Philosophical Investigations might have harbored the turning point in analytic philosophy, but the possibility has petered out. Neither have Dewey's or Kuhn's contributions succeeded in this regard. On the phenomenological side, the most promising criticism has gone astray. I refer to Maurice Merleau-Ponty's unfinished The Visible and the Invisible . But, at least roughly, analytic philosophy (including a strong externalist reading of Kant) and Husserlian phenomenology (but not late phenomenology) have played rather similar roles in their respective worlds.

6. The verbal distinctions may be a little too densely packed. The terms are used expressly by Husserl to identify the failing of the epistemological tradition

from Galileo to Kant ("naturalism") and his own corrective ("phenomenology"). The clearest account of Husserl's use is given in a pair of papers published in recent years as a small book. See Edmund Husserl, Phenomenology and the Crisis of Philosophy, trans. Quentin Lauer (New York: Harper and Row, 1965). By theorem (5.6), I signal the fact that Husserl's disjunction can't possibly work, although it would be fair to say that "naturalism" must be phenomenologized and "phenomenology" naturalized. Hegel's usage is quite different, for Hegel is attempting to overcome the aporia of Kant's distinction between phenomena and noumena. See Hegel, Phenomenology of Spirit . See, also, Jean Hippolyte, Genesis and Structure of Hegel's Phenomenology of Spirit, trans. Samuel Cherniak and John Heckman (Evanston: Northwestern University Press, 1974), especially part 7.

7. Without comparing their respective philosophical abilities, I should say that Jürgen Habermas plays a role with respect to Frankfurt Critical philosophy that is not very different from the role Quine plays with respect to pragmatism (particularly, Dewey's brand). For both outflank any trace of historicity. Habermas's effort is the odder of the two, since his work is regarded, somehow, as the fulfillment of the Frankfurt School's endeavor, whereas there is no sense of anything like that in Quine's work. (In a very thin way, something of the sort may be said of Putnam, who, as I have indicated, is also wrestling with a Kantian demon.) A great deal of the work of Horkheimer and Adorno was directed precisely at dismantling the conviction of Enlightenment philosophy—along historicist lines. I cannot say that Habermas is the apotheosis of Enlightenment mentality, but he aspires to something like it, replacing his original inspiration (Marx) with Kant. In this, he has fallen completely under the philosophical spell of Karl-Otto Apel, who is a frank apriorist of the Kantian sort, although an ingenious one. The theme of legitimation has troubled Habermas through his entire career: he has oscillated between a "transcendental" (Kantian) sense of legitimation and what he now calls a "pragmatic" form. But his difficulty here is the perfect analogue of Putnam's (analyzed earlier: that is, the difficulty associated with Putnam's use of the Kantian theme of the Grenzbegriff ). On the Frankfurt School philosophers, see Theodor W. Adorno, Negative Dialectics, trans. E. B. Ashton (New York: Seabury Press, 1973); Max Horkheimer and Theodor W. Adorno, Dialectic of Enlightenment, trans. John Cumming (New York: Seabury Press, 1972); and, explicitly against Husserl and implicitly (in anticipation) against Habermas, Against Epistemology: A Metacritique, trans. Willis Domingo (Oxford: Basil Blackwell, 1982). On Apel, see Towards a Transformation of Philosophy .

8. W. V. Quine plays a double game with "holism." By one strategy—generalizing well beyond Pierre Duhem's well-known thesis about a certain indeterminacy in disconfirming theoretical claims in science (among distributed propositions)—Quine arrives at his "indeterminacy of translation" thesis; by another—illicitly disjoining word and sentence—he leads us to the cognitive privilege associated with his use of "holophrastic" sentences. The first theme belongs chiefly to Word and Object (Cambridge: MIT Press, 1960) but is also thought to have the blessing of his treatment of the analytic/synthetic dogma. The second has a more obscure inning in Word and Object, particularly in

connection with the delayed relevance of "analytical hypotheses" (which, in effect, reserves a space in which sentences may escape the stalemate intended by the first sort of holism). It reappears, more robustly and more explicitly, in Pursuit of Truth, in the form of "holophrastic" sentences. There, effectively, Quine reverses the line of argument directly against Carnap and the search for Protokollsätze . For a sense of Duhem's rather different thesis, see Pierre Duhem, The Aim and Structure of Physical Theory, trans. Philip P. Wiener (Princeton: Princeton University Press, 1954).

9. This is the generic form of nearly all analytic theories of knowledge. One may well claim that the late naturalism of the analytic sort is primarily concerned to construe JTB in suitably naturalized terms. This accounts in part for the interest in the disquotational theory of truth. For a sense of how recent efforts of the naturalizing kind have gone, see Alvin I. Goldman, Liaisons: Philosophy Meets the Cognitive and Social Sciences (Cambridge: MIT Press, 1992). For its application to the sciences, see Philip Kitcher, The Advancement of Science: Science without Legends, Objectivity without Illusions (New York: Oxford University Press, 1993). For an overview of the original doctrine, see Chisholm, Theory of Knowledge .

10. Quite early in his career, Davidson sought to construe rationalization ("explanation by reasons") as a species of causal explanation ("explanation by causes") on the grounds (independently reasonable) that "having a reason" could be a cause for one's action. The non sequitur is plain enough. But what is important about it concerns the fortunes of naturalism (in the late analytic sense). For, for one thing, it might (if it worked) undercut second-order legitimation; for another, it might smooth the way for a benign form of nonreductive physicalism (in effect, what is now called supervenience) by neutralizing the holism of our models of rationality. Davidson's insight here is more ingenious. The trouble is that there's no argument to back it up. See Donald Davidson, "Actions, Reasons, and Causes" and ''Mental Events," in Essays on Events and Actions (Oxford: Clarendon, 1980). I shall come to the second issue later.

11. See Putnam, Renewing Philosophy, ch. 3.

12. Edmund Gettier's famous little paper, "Is Justified True Belief Knowledge?" Analysis 23 (1963), produced a cottage industry designed to recover JTB from obvious mortal threats. Its effect was misperceived by analytically minded philosophers. For what it actually demonstrates is, first, that there are always antecedent questions that must be answered before any "standard" logic can be supposed to be applicable to the fine-grained questions of the domain to which it is applied; and, second, that what is to count as "knowledge" cannot be altogether freed from legitimative concerns. It is an irony that Gettier's implicit challenge should have gone largely unexamined.

13. I regard it as a telltale clue that naturalistic epistemologists very often have no developed theory of persons or selves to offer. This is noticeably true of Quine, in "Epistemology Natualized" and in Goldman, Liaisons . The strategies that would be required if naturalism were to go through are easily specified, of course. But they are characteristically scanted. See, for instance, Davidson, "Mental Events"; and D. C. Dennett, Content and Consciousness (London: Routledge and Kegan Paul, 1969). I shall introduce a little later the fashionable

notion "supervenience," which is perhaps the most potent feint the naturalists have perfected in order to obviate the difficulties now looming.