1 Introduction

More than half a century ago, W. V. Quine published Word and Object, a book that is widely viewed as one of the most influential monographs of twentieth-century philosophy. In that book, Quine presents his seminal views on language, science, and ontology, and incorporates them in a new and comprehensive naturalistic framework; a metaphilosophy in which all forms of inquiry—philosophy, science, and common-sense—are viewed as part of a single continuous enterprise.

Word and Object has had a long-lasting influence on analytic philosophy. Not only have Quine’s views on language “forced upon the philosophical world” a “process of thinking and rethinking” what we mean by translation and meaning (Putnam 2002, p. 274), his ideas about the relation between philosophy and science have arguably been the most significant influence on what is often called the “naturalistic turn” in contemporary philosophy (Leiter 2004, pp. 2–3).

Despite the book’s influence, however, little is known about the genesis and development of Quine’s ideas. Although historians of analytic philosophy in recent years have shown an increasing interest in post-war analytic developments, there is still much to be learned about the evolution of Quine’s views.Footnote 1 Fortunately, an astonishing amount of documents relating to the development of Quine’s views—notes, academic and editorial correspondence, drafts, lectures, teaching materials, and grant proposals—has been saved and stored at the W. V. Quine Papers at Houghton Library. These documents provide a unique opportunity to minutely reconstruct the evolution of Quine’s ideas in a crucial stage of his development, i.e. the period in which he grew from a respected logician to a world-leading philosopher.

In this paper, I will discuss a large series of notes, letters, and manuscripts from the 1940s and early 1950s—documents which show that Quine, from the early 1940s onwards, started working on his first philosophical monograph, a book entitled Sign and Object. The Houghton archives contain several sets of autograph and type written notes from the 1941–1946 period connected to what Quine has called his “book on ontology”.Footnote 2 These documents, I argue, reveal how Quine gradually evolved from a Carnapian into a naturalist philosopher, thereby clarifying both his development and his mature perspective.

Quine’s mature naturalism consists of two basic elements: (1) the observation that as inquirers we all start in the middle, assimilating our ‘inherited world theory’; and (2) the view that we cannot but work from within this inherited system as we go along, relying on our best theories and methods.Footnote 3 Since epistemological and metaphysical questions are traditionally interpreted as ‘transcendental’ questions (i.e. as questions external to our best theories and methods), the story of Quine’s development is partly a story of his evolving views about how we should (re)interpret such questions if we are to be truly working from within. This paper uses the documents related to Sign and Object to show how Quine gradually starts to dismiss (his interpretation of) Carnap’s solutions to this problem—i.e. developing a ‘logic of science’ in which metaphysical statements are dismissed as quasi-syntactical and in which an analytic–synthetic distinction is used to account for our logical and mathematical knowledge—and to replace them with his mature solution that we can reinterpret traditional epistemological and metaphysical questions as scientific questions.Footnote 4

Thus far, Quine’s first philosophical book project has gone completely unnoticed in the literature.Footnote 5 In this paper, I aim to contribute to our understanding of the development of Quine’s philosophy by reconstructing his position in Sign and Object as well as the developments that led Quine to give up on the project in 1946. I argue that although Sign and Object was naturalistic in many respects, Quine encountered significant problems in formulating his position, problems which shed new light on Quine’s early position, his evolving views about Carnap’s philosophy, and the place of “Two Dogmas of Empiricism” in Quine’s oeuvre.

This paper is structured as follows. After a sketch of the philosophical background of Quine’s book project (Sect. 2), I introduce his method of inquiry in Sign and Object and examine a note on “the nature of metaphysical judgments”, showing that Quine still defends a mixture of Carnapian and mature views in 1941 (Sects. 34). Next, I show that Quine adopts a fully naturalistic metaphysics in 1944 (Sect. 5), but postpones his book project because he fails to come up with satisfying solutions to problems in epistemology and the philosophy of language (Sect. 6). I argue that although “Two Dogmas of Empiricism” is widely considered to be a breakthrough in his thinking, Quine himself was largely dissatisfied with the paper because he felt that he had failed to provide solutions to these problems (Sect. 7). In the final sections, I reconstruct the development of Quine’s alternative to Carnap’s picture by studying a series of unpublished papers, letters and lectures on epistemology, papers which led Quine to reboot his book project, eventually culminating in Word and Object (Sects. 89).Footnote 6

2 Philosophical background

Although Quine primarily thought of himself as a logician in the 1930s, philosophy was never far away; while his early publications are outwardly technical, many of them implicitly intend to clarify problems in ontology, semantics, and the philosophy of mathematics. Looking back on his earliest work, Quine argues that even his dissertation was already “philosophical in conception”. Actively concerned with the paradoxes in logic and set theory, Quine aimed to transform logic and mathematics as simply and as economically as possible, thereby aspiring “to comprehend the foundations of logic and mathematics and hence of the abstract structure of all science” (Quine 1985, p. 85).Footnote 7

More overtly philosophical was Quine’s active concern with the ontological presuppositions of logical frameworks. Not only was he already interested in the relation between logic and ontology in his Warsaw discussions with Stanisław Leśniewski in May 1933,Footnote 8 also in one of his very first publications—“Ontological Remarks on the Propositional Calculus”—Quine adopts an explicitly ontological perspective on logical systems, arguing that we ought to eliminate propositions because

the whole notion of sentences as names is superfluous and figures only as a source of illusory problems. Without altering the theory of deduction internally, we can so reconstrue it as to sweep away such fictive considerations; we have merely to interpret the theory as a formal grammar for the manipulation of sentences, and to abandon the view that sentences are names.Footnote 9 (1934c, p. 59)

A few years later, at the 1939 International Congress for the Unity of Science, Quine first presented his criterion of ontological commitment.

A related philosophical development can be distilled from Quine’s early work on nominalism. Although Quine claims to have already “felt a nominalist’s discontent with classes” in 1933 (1986a, p. 14), his early work on the matter seems to be at least mildly sceptical.Footnote 10 This attitude seems to change somewhat, however, when Quine—in the 1940–1941 Harvard Logic Group meetings with Carnap, Tarski, Goodman, and Russell—discusses the prospects of a finitist-nominalist language of science.Footnote 11 Although Quine, in one of the meetings, presents a paper in which he argues that he does not “insist on eliminating classes or other unthingly objects” because it “is not clear that the unthingly can be eliminated without losing science” (December 20, 1940, item 2954), he seems to intensify his attempts to “set up a nominalistic language in which all of natural science can be expressed” (1939a, p. 708) in the years immediately following the meetings—attempts that eventually culminate in his joint paper “Steps toward a Constructive Nominalism” (Goodman and Quine 1947).Footnote 12

A final development that seems to have contributed to Quine’s increased philosophical aspirations in the early 1940s is his growing discontent with Carnap’s views on language and ontology. Where Quine seems to have defended a largely Carnapian perspective on the nature of philosophy in the earliest stages of his career,Footnote 13 he grows more sceptical of the latter’s views during the second half of the 1930s, as is evinced by his explicit opposition to Carnap during the Harvard Logic Group meetings.Footnote 14

Considering these developments—his first formulation of the criterion of ontological commitment, his increased concern with the status of abstract objects, and his growing discontent with Carnap’s philosophical system—it is not surprising that Quine, after finishing his third logical (text)book in 1940,Footnote 15 decided to devote a more substantial part of his time to philosophy. Indeed, in a grant application from January 1941, Quine applies for a small sum of money for secretarial assistance in connection with, among others, investigations into “the philosophical presuppositions of science”, a proposal that is heavily influenced by the discussions in the Harvard Logic Group. For Quine proposes to investigate

(a) The ontological presuppositions of mathematics and natural science. [...] Can science be formulated as not to presuppose universals? (b) The problem of infinity, and its connection (via the Skolem–Löwenheim Theorem) with the problem of universals. (c) The epistemological difference, if any, between mathematics and natural science. (January 9, 1941, item 475)

The earliest evidence of Quine’s plan to write his first philosophical monograph in connection with these (and other) investigations is from November 1941, when he wrote a four-page untitled book outline.Footnote 16

3 Starting at the middle

Quine’s book outline shows that he planned to write a book that is fairly comprehensive in philosophical coverage; the seven chapters he envisions are titled (1) A tentative ontology, (2) Time and tense, (3) Sign and object, (4) Extensionality, (5) Meaning, (6) The place of epistemology, and (7) Nominalism and empiricism (November 1941, item 3169, my transcription). From a developmental perspective, one of the most interesting parts is Quine’s outline of the opening chapter, which begins as follows:

Starting at the middle: an ontology that may want supplementation or diminution. (Concrete) things in some sense or other (spatio-temporal regions, or quanta of action, or bundles of quanta of action, etc., for the present left undecided), and all attributes and relations of such things, and all attributes and relations of the thus supplemented totality, and so on.

   Just what attributes and relations are there? Well, common-sense partial answer is that every condition we can formulate (everything of the form of a statement, but with a variable in place of one or more signs of entities) determines an attribute of just the entities fulfilling that condition, a relation of just the n-ads of entities fulfilling that condition. (Roughly: whatever we say about an object attributes an attribute to that object; and so on). This is the principle of abstraction (comprehension).

   [...] But not so fast. Even principle of abstraction untenable! (Paradoxes.) There must be some conditions with no attributes or relations corresponding. A modicum of nominalism is thrust upon us despite our having begun with ever so willing a Platonism. (November 1941, item 3169, my transcription)

Although Quine’s argument is still rather sketchy, several elements are interesting from a contemporary perspective. First and foremost, it should be noted that Quine uses a largely naturalistic method of inquiry. Like the first section of Word and Object, in which he argues that “we all must start in the middle”, and literally opens with the “familiar desk” that “manifests its presence by resisting my pressures and by deflecting light to my eyes” (1960, Sect. 1), Quine, in his outline, is also ‘starting at the middle’. Moreover, Quine’s ideas about what constitutes ‘the middle’ resemble his later views as well. Just as in Word and Object, ‘the middle’ seems to refer to a mixture of science and common sense. After all, Quine starts with both a scientific ontology (‘quanta of action’) and with what he himself calls the common-sense view about attributes.Footnote 17

Second, the model of inquiry presupposed in these opening remarks is consistent with his mature view that although we start at the middle, we are trying improve this system from within. For although Quine seems to want to settle on a nominalistically acceptable ontology,Footnote 18 he justifies this decision by appealing to the paradoxes he encounters while working from within his common sense idea about attributes and relations. Although Quine is starting at the middle, in other words, he is emphasizing that this starting point ‘may want supplementation or diminution’.

4 The nature of metaphysical judgments

Despite the apparent continuity between his early and his mature views about the nature of inquiry, however, there is evidence that Quine did not or could not yet completely practice what he preached. In this section, I argue that Quine had not yet completely worked out how to naturalize his ideas about metaphysics.

In 1939, as we have seen, Quine first set out his criterion of ontological commitment in a paper for the Harvard conference on the Unity of Science.Footnote 19 Despite Quine’s ontological breakthrough, however, his paper is neutral with respect to the traditional questions of metaphysics. After all, it solely deals with the question what entities we are committed to if we accept a particular language.Footnote 20 It remains an open question what language we are to adopt—a question whose answer depends on one’s views about metaphysics.Footnote 21

The details of Quine’s early views about metaphysics become clearer when we turn to his 1941 book outline. For, in the outline, Quine also explicitly states his broader, more general, perspective on the nature of metaphysical existence claims. On the very first page, even before the above-discussed sketch of the first chapter, Quine argues that metaphysical statements are factual but that they cannot be evaluated rationally:

Nature of metaphysical judgments:

As factual as any; not quasi-syntactical. But can’t be criticized in the way other factual judgments can, because they concern the very fdtns. of the conceptual scheme relative to which we criticize other judgments. Bootstraps (Kant).

   What can be criticized is an analogue, viz: A believes such & such metaphysical statement. Here we do examine A’s language to decide; insofar, Carnap right. But the analogue is not equivalent.

   Of course there is also met. that is bad because of vagueness; and to be expected, since, as observed, not subject to control. (November 1941, item 3169, my transcription)

There is much to unpack in this short passage. A first thing that is remarkable from a contemporary perspective is that Quine distinguishes between metaphysical statements (first paragraph) and ontological commitments (second paragraph) and explicitly claims that the two are ‘not equivalent’. Where the mature Quine collapses the distinction between ordinary and metaphysical existence claims by arguing that we can answer the question whether or not x’s actually exist by answering the question whether or not our best scientific theories commit us to x’s, here he seems to claim that although questions about ontological commitments can serve as an ‘analogue’ of metaphysical judgments, they are not completely alike.Footnote 22

Second, even if we accept Quine’s distinction between ontological commitments and metaphysical existence claims, his ideas about these metaphysical judgments are remarkable from a contemporary perspective as well; for although Quine holds that metaphysical statements are factual, he also maintains that they cannot be criticized, i.e. that they are ‘not subject to control’. Where Quine’s distinction between metaphysical and ordinary existence claims in the first and second paragraph still seems to be in Carnapian spirit—corresponding, somewhat anachronistically, to the latter’s external and internal questions (1950) respectively—he proposes an important emendation here. He agrees with Carnap that metaphysical judgments cannot be rationally evaluated, but he does not want to succumb to the latter’s suggestion that these questions are without cognitive content. Indeed, he implicitly refers to Carnap in claiming that metaphysical existence claims are not ‘quasi-syntactical’ but ‘as factual as any’.Footnote 23

It is my contention that there are two fundamental reasons for Quine’s discontent with Carnap’s quasi-syntactical approach. First, Quine seems to believe that Carnap’s position is too easy—that he is dodging his ontological commitments. Just as Quine in 1932 had tried to convince Leśniewski that “his system of logic did not avoid, as he supposed, the assuming of abstract objects” (TML, 1985a, p. 104), he also felt that Carnap could not avoid being committed to abstract objects, even if he was dismissing metaphysical claims as quasi-syntactical. In his 1937 lecture on “Nominalism”, for example, Quine describes Carnap as a ‘second-order nominalist’ and subtly accuses him of taking the easy way out:

Carnap has been considered a nominalist, though he doesn’t incline to the sacrifices of the intuitionist. But he is a nominalist only in a very different sense. A nominalist of second intention: Doesn’t nominalize universals, but nominalizes the problem of universals.

[...]

Nominalism in its ordinary form has perhaps two purposes: 1st) to avoid metaphysical questions [...] 2nd) To provide for reduction of all statements to statements ultimately about tangible things, matters of fact. This by way of keeping our feet on the ground—avoiding empty theorizing. Carnap’s 2[n]d-degree nominalism succeeds in the 1st respect [...] But it accomplishes nothing in the 2nd respect. (October 25, 1937, item 2969, my transcription)

According to Quine, in other words, Carnap’s second-order approach serves as some sort of ontological free pass; it allows us to talk about abstract entities without worrying about our ontological commitments. Or, as he would put it even less sympathetically almost 10 years later:

Logical positivists didn’t take Platonistic implications of math. seriously. They were opportunistic: argued against metaphysics as non-empirical because they didn’t like it; admitted math. unquestionably because they like it. (ca. 1947, item 3266, my transcription)

The second problem Quine has with Carnap’s account concerns the details of the latter’s quasi-syntactical treatment of metaphysical existence claims. Quine does not only dismiss the effects of the latter’s quasi-syntactical approach, he also rejects the very idea that metaphysics ought to be dismissed as meaningless. In a 1937 note—titled “A Pragmatic Interpretation of Positivism”— Quine rejects Carnap’s appeal to a strict criterion of significance in dismissing metaphysics:

Meaninglessness must be abandoned as meaningless—at least insofar as it might be used against metaphysics. Even supposing we would make sense ultimately of an operational criterion this would rule out all the non-intuitionistic part of math. also.Footnote 24 (April 2, 1937, item 3169, my transcription)

Quine, in sum, has two problems with Carnap’s perspective on ontology and metaphysics. He believes (1) that Carnap’s solution is too easy as it allows us to talk about abstract objects without worrying about ontological commitments; and (2) that we should get rid of the idea that metaphysics is meaningless.

The mature Quine provides a plausible explanation as to why metaphysical judgments are factual instead of quasi-syntactical. For in giving up on the analytic–synthetic distinction and, thereby, the distinction between ordinary and metaphysical existence claims, metaphysical questions are equated with regular queries about ontological commitments, i.e. questions that can only be distinguished from scientific queries in “breadth of categories”. Where the natural scientist deals with “wombats and unicorns” and simply assumes a realm of physical objects, the metaphysician/ontologist scrutinizes the question whether we ought to accept “the realm of physical objects itself” (1960, p. 275). This is not the solution Quine adopts in his outline however. After all, Quine’s mature position implies that metaphysical judgments can be criticized: just as we can rationally evaluate the natural scientist’s claim that there are no unicorns, we can evaluate the ontologist’s claim there are no abstract objects.

The first outline of Sign and Object, in other words, still presents a mixture of Carnapian and mature views. Quine argues that metaphysical statements are factual (and not quasi-syntactical), but he still agrees with Carnap that they cannot be criticized, showing that he had not yet completely dismissed Carnap’s argument for rejecting metaphysical statements. The result is an apparently inconsistent mixture of ideas about the relation between metaphysics and ontology. For it is unclear how Quine, given his strong empiricist commitments, would have explained that metaphysical claims are factual even if they are not ‘subject to control’.

5 The philosopher’s task

Between September 1942 and November 1945, Quine served as a full lieutenant (and later as a lieutenant commander) in the Navy. As a result, Quine’s research time was severely limited for more than 3 years. In a 1942 letter to Alonzo Church, the main purpose of which was to announce that he was resigning as the consulting editor of the Journal of Symbolic Logic, Quine writes that “every bit of time that I can spare from teaching duties must go into war work” and that he has dropped his “research for an indefinite period”:

Before Dec. 7 [the date of the attacks on Pearl Harbor, SV], I was outlining a little philosophico-logical book to be entitled Sign and Object. All I can hope to do now is synopsize the main ideas, eventually, in a brief article; and I’m not going to think about this, even, till 6 months or so hence, when teaching and war work have resolved their mutual conflict somehow.Footnote 25 (February 15, 1942, item 570)

Despite the fact that Quine had to relegate all his research activities to spare time, there are strong indications that he never stopped working on Sign and Object during his Navy years. For the majority of Quine’s notes for the book project are from this period.Footnote 26

For our present purposes, one of the most interesting documents is a series of notes from October and November 1944, in which Quine explicitly reflects on the relation between philosophy and science and seems to have resolved his earlier, theoretically awkward, view that metaphysical statements are factual but unchallengeable.Footnote 27 Where the above-discussed outline from 1941 at best indicates that Quine’s ideas about the nature of inquiry were already fairly naturalistic, these notes leave no doubts about the maturity of his ideas in the early 1940s. For not only does Quine implicitly adopt a “starting at the middle” approach like in his earlier outline, he also explicitly adopts a naturalistic view in answering the question of how we ought to conceive of the relation between science and philosophy.Footnote 28 Comparing the philosopher’s task with the aims of science and mathematics, Quine writes:

The philosopher’s task differs from that of the natural scientist or mathematician, no less conspicuously than the tasks of these latter two differ from each other. The natural scientist and the mathematician both operate within an antecedently accepted conceptual scheme but their methods differ in this way: the mathematician reaches conclusions by tracing out the implications exclusively of the conceptual scheme itself, whereas the natural scientist gleans supplementary data of what happens around him. The philosopher, finally, unlike these others, focuses his scrutiny on the conceptual scheme itself. (November 5, 1944, item 3181, my transcription)

Quine’s perspective on the philosopher’s task appears to be well developed. Still, this paragraph could be interpreted as compatible with Quine’s 1941 perspective on metaphysics. After all, the idea that the philosopher ‘focuses his scrutiny on the conceptual scheme itself’, might lead one to suspect that Quine still believes that the philosopher’s statements “can’t be criticized in the way other factual judgments can” (November 1941, item 3169, my transcription). The next paragraph of the 1944 note, however, rules out this interpretation, thereby showing that Quine had changed his mind:

It is understandable, then, that the philosopher should seek a transcendental vantage point, outside the world that imprisons natural scientist[s] and mathematician[s]. He would make himself independent of the conceptual scheme which it is his task to study and revise. “Give me \(\pi \hbox {o}\upsilon {\upsigma }{\uptau }{\upomega }\) [a place to stand, SV]” Archimedes said, “and I will move the world”. However there is no such cosmic exile. The philosopher cannot study and revise the fundamental conceptual scheme of science and common sense, without having meanwhile some conceptual scheme, whether the same or another no less in need of philosophical scrutiny, in which to work. The philosopher is in the position rather, as Neurath says, “of a mariner who must rebuild his ship on the open sea”. (November 5, 1944, item 3181, my transcription)

The similarity with his mature position is remarkable.Footnote 29 Where Quine in his early notes seems to allow factual but unchallengeable metaphysical judgments concerned with ‘the very fdtns. of the conceptual scheme relative to which we criticize other judgments’, he seems to be fully committed to a naturalized metaphysics in 1944.Footnote 30

6 Two problems

Despite these similarities between Sign and Object and Word and Object, Quine was dissatisfied with the progress he was making. In a 1944 letter to Goodman, written shortly after he had drafted his second, more detailed, outline (October 4, 1944, item 3169), he complains about the book’s progress:

In the matter of logic and philosophy, I’m at more of a standstill than I have been for half a generation. Still dickering with the introduction of a book on ontology.Footnote 31 (December 19, 1944, item 420)

It is probably because of this reason that Quine decided to postpone his work on Sign and Object in 1946 and to let his philosophical ideas simmer for a few years in his new course on the philosophy of language.Footnote 32

For the purposes of this paper, it is important to see why Quine was dissatisfied with the progress he was making. It is my contention that there are two fundamental reasons as to why Quine struggled to complete Sign and Object. First, Quine had yet to develop a comprehensive view about language, meaning, and the nature of logical and mathematical knowledge. Quine had been dissatisfied with Carnap’s analytic–synthetic distinction for years, but he had not been able to formulate a satisfying alternative. Although he had succeeded to define analyticity in terms of synonymy in 1943,Footnote 33 he really struggled to find a satisfying behavioristic explication of synonymy. Indeed, one of the most detailed notes from Quine’s Navy years is a document entitled “Foundations of a Linguistic Theory of Meaning” (August 1943, item 3169), in which he examines and dismisses some candidate explications of synonymy. The problem was that even if Quine would decide to abandon the whole project of appealing to an analytic–synthetic distinction to account “for the meaningfulness of logical and mathematical truth” (1986b, pp. 206–207), he had “no suggestion of a bright replacement” (1991, p. 393). Indeed, in a 1948 letter to Hugh Miller, Quine sums up his predicament pretty well:

I am with you in questioning the currently popular boundary between analytic and synthetic. I feel, indeed, that the distinction means virtually nothing, pending the devising of some behavioristic criterion such as no semanticist to date has given us an inkling of. But, for the same reason, I don’t know what it would mean to say, with you, that arithmetic is not analytic. (May 31, 1948, item 724, my transcription)

A second reason for Quine’s dissatisfaction with his philosophical progress is the fact that he had not yet been able to develop a satisfying epistemology. Although he had accepted, as we have seen, a fully realistic materialist ontology in all of his notes, he continuously struggled with the phenomenalist objection that primary sense experiences are ‘more real’ than tables, chairs, atoms, and electrons:

There is a sense in which physics might be said to be concerned with explaining the nature of reality. And who contests this? Primarily the Idealist [...] The Idealist would take the perceptions etc. rather as the basic reality, and derive things as constructions, logical constructs (Russell). The study of how to make these constructions is Epistemology. And things are composed not of atoms but of perceptions, sense qualia etc. (October 4, 1944, item 3169, my transcription)

Where Quine would later dismiss phenomenalism by arguing that sense data are scientific posits and therefore not in any way more fundamental than, for example, triggerings of sense receptors, he had yet to develop a satisfying response to phenomenalism in the early 1940s.Footnote 34

This ‘problem of epistemic priority’ is one of the most significant problems Quine grappled with in the 1940s. There are two distinct, though related, explanations for Quine’s preoccupation with the problem. First and foremost, Quine’s two philosophical heroes, Rudolf Carnap and Bertrand Russell, had both defended a phenomenalist perspective at one point or another. Quine was an admirer of Carnap’s Aufbau and had heard Russell defend phenomenalism in his 1940 William James lectures “An Inquiry into Meaning and Truth” at Harvard.Footnote 35

A second explanation for Quine’s struggle with epistemological priority is the fact that the issue had been debated in the 1940–1941 Harvard Logic Group meetings.Footnote 36 In his notes of one these meetings, Carnap writes: “We have not agreed among ourselves whether it is better to begin with thing-predicates or sense-data-predicates. For the first: I and Tarski; Hempel follows Popper. For the second: Goodman and Quine” (June 18, 1941).Footnote 37

In sum, although Quine had developed a naturalistic picture of inquiry in Sign and Object, he started to view the book as “a distant objective” (May 16, 1948, item 921) because he was confronted with two theoretical challenges: (1) he saw no plausible alternative to Carnap’s analytic–synthetic distinction, and (2) he had not been able to develop a satisfying epistemology. Indeed, when Quine, in 1946, was asked to suggest topics for a Rockefeller conference on the most urgent questions in philosophy (“the work which philosophy in the United States now has to do”), he replied by listing the problem of ‘cognitive meaning’ and the problem of ‘epistemic priority’ as his main concerns:

Clarification of the notion of cognitive meaning, or of the relation of cognitive synonymy of phrases, is needed in order to make sense of the distinction between analytic and synthetic judgments [...] there has been little recognition of the fact that the distinction in its general form is undefined pending a definition of cognitive synonymy. (My own view is that the latter definition should be couched in terms of observable linguistic behavior. I have found no satisfactory formulation).

   Clarification of the notion of epistemology priority is needed in order to know what the task of epistemology (as distinct e.g. of psychology) is; for, epistemological priority is the direction in which epistemological reduction of knowledge to more fundamental or immediate knowledge seeks to progress. (October 20, 1946, item 921)

7 Two dogmas

In January 1950, Max Black invited Quine to read a paper for the APA Eastern Division meeting in Toronto with the specific request to survey “what questions and issues remain still to be settled in the light of the programs and achievements of the previous half century’s work” (January 17, 1950, item 31). Quine hesitated (“I am not at my best in historical surveys”), but accepted the invitation after Black clarified that the Program Committee was specifically interested in “an analysis of the achievements to date and an evaluation of the questions which remain in need of further investigation” (January 20 and February 6, 1950, item 31).

The paper Quine read in Toronto, “Two Dogmas of Empiricism”, was immediately recognized to be of major importance. Within 6 months after the APA meeting, three events were organized to discuss the paper. In February 1950, Chicago’s Department of Philosophy organized a debate between Carnap and Quine; in May 1950, there was a symposium on the paper at Stanford; and in the same month The Institute for Unified Science sponsored two sessions with papers on “Two Dogmas” (June 18, 1951, item 1200).Footnote 38 Moreover, Quine received dozens of letters with questions, comments, and requests for copies in the year after he first read the paper.Footnote 39

Despite this widespread recognition that he had written an important paper, Quine felt that the massive attention for ‘Two Dogmas’ was largely undeserved. In response to a letter by Paul Weiss, for example, Quine writes:

my rather tentative negative strictures on analytic–synthetic have had plenty of attention, disproportionate attention [...] I might feel differently if the doctrine concerned were a positive philosophy. But what is it? (a) The observation that the analytic–synthetic distinction has never been adequately def’ned, though all too widely taken for granted. (b) The tentative conjecture that epistemology might develop more fruitfully under some very different sort of conceptualization, which I do not provide. (c) The suggestion that the analytic–synthetic idea is engendered by an untenably reductionistic phenomenalism. (June 18, 1951, item 1200, my transcription)

Quine, in other words, felt that his paper’s main contribution was negative and that he had failed to develop a satisfying alternative.Footnote 40

Whether or not one agrees with his own assessment of ‘Two Dogmas’, Quine’s dissatisfaction with the paper is perhaps less of a surprise if we reconsider the problems that led him to postpone Sign and Object in the mid-1940s. Quine’s first problem was to find a satisfying alternative to Carnap’s analytic–synthetic distinction. Now, although Quine, in ‘Two Dogmas’, abandons the dogma that “there is a fundamental cleavage between truths which are analytic [...] and truths which are synthetic (1951a, p. 20), the alternative picture he outlines in the famous sixth section of the paper is sketchy at best. Even in the paragraph in which he tries to clarify what he means with “without metaphor”, his definition does not seem to satisfy his own strict behavioristic standards of clarity:

For vividness I have been speaking in terms of varying distances from a sensory periphery. Let me try now to clarify this notion without metaphor. Certain statements [...] seem peculiarly germane to sense experience [...] Such statements, especially germane to particular experiences, I picture as near the periphery. But in this relation of “germaneness” I envisage nothing more than a loose association reflecting the relative likelihood, in practice, of our choosing one statement rather than another for revision in the event of recalcitrant experience. (1951a, p. 43)

Although we tend to read Quine’s mature epistemology (including his ideas about observation sentences, language learning, and the nature of scientific theories) into statements like these, the picture outlined here is still very sketchy. Indeed, in response to a critical letter, Quine admits that “there is [...] much more to be said” about notions like “a ‘convenient conceptual scheme’ and a ‘recalcitrant experience’, and much that I am not yet able to say” (April 17, 1951, item 231).Footnote 41

The sketchiness of Quine’s positive account becomes even clearer if we reconsider the second problem discussed in Sect. 7, i.e. the problem of how to formulate a satisfying response to epistemological phenomenalism. Where the last section of ‘Two Dogmas’ at the very least contains Quine’s first step towards the solution of his problem with the analytic–synthetic distinction, it does not address his problem with phenomenalism at all.Footnote 42 If anything, Quine seems to have adopted a phenomenalistic picture of epistemology himself in explicating the experiential boundaries of his metaphorical “man-made fabric” (1951a, p. 42) in terms of “sense data” (ibid., 44).

Quine, in other words, appears to presuppose a holistic variant of epistemological phenomenalism in ‘Two Dogmas’: there are pure uninterpreted sense data and there is a conceptual scheme which is to account for those raw experiences as simply and as effectively as possible.Footnote 43 Quine’s picture, in sum, still seems miles away from a naturalized epistemology in which all talk of science-independent sense data is abandoned and replaced with talk about the physical stimulation of sensory receptors. Indeed, in response to questions from Percy Bridgman and Henry Margenau, Quine explains that it is his aim to “give to the conceptual scheme everything except the raw confirmatory experiences, & to find the external purpose of the conceptual scheme in those experiences” (May 1951, item 3015, my transcription and emphasis).Footnote 44

8 Language and knowledge

Despite the substantial gap between the phenomenalism in ‘Two Dogmas’ and his mature naturalized epistemology, Quine solved his epistemological problems only 1 year later. In October 1952, Quine read a paper entitled “The Place of a Theory of Evidence” at Yale. The first half of the lecture discusses the familiar idea that, from an epistemological point of view, both everyday and scientific objects are myths, the function of which is to anticipate “immediate subjective experience” (October 7, 1952, item 3011, p. 15). In the second half of the paper, however, Quine develops a new argument. After concluding that even memories of past sense data do not qualify as epistemically ‘pure’, such that only present sense data are available as an epistemological foundation, Quine argues:

let us take account of the ridiculousness of our position [...] The pursuit of hard data has proved itself, at this point at least, to be self-defeating [...] What has been said just now against [...] memory applies in some degree to the stream of sensory experience generally [...] our selective awareness of present sensory surfaces is a function of [...] past conceptualizations. [...] it is not an instructive over-simplification but a basic falsification, to represent cognition as a discernment of regularities in an unadulterated stream of experience. Better to conceive of the stream itself as polluted, at each succeeding point of its course, by every prior cognition [...] We would do well to recognize that in seeking to isolate sense data we are not plumbing the depths of reality. (October 7, 1952, item 3011, pp. 17–19)

Quine, in other words, argues that sense data cannot provide a science-independent epistemological foundation because they are themselves scientific posits.Footnote 45 And he immediately draws the naturalistic conclusion that if there is no epistemological foundation to be had, we can view “epistemology as an empirical science” and replace talk about sense data with talk about “the barrage of physical stimuli to which [a man’s] end organs are exposed” (ibid., pp. 23–25).

Quine, in sum, had solved his problem with phenomenalism by recognizing that sense data do not offer an external vantage point, an idea that perfectly matches the general picture of inquiry he had already sketched in his notes for Sign and Object. Interestingly, Quine’s breakthrough in epistemology also leads him to solve his first problem. After all, his new conception of ‘epistemology as an empirical science’ provides him with the opportunity to develop an alternative to Carnap’s epistemology, i.e. a positive story about scientific, logical and mathematical knowledge that does not rely on an analytic–synthetic distinction. Indeed, only a few months after his Yale lecture, Quine first expresses his mature view that “[w]e can still study the ways of knowing” by studying “the learning of language” and “the acquisition of scientific concepts”; i.e. by studying “the relation of sensory stimulation to the production of scientific hypotheses by people” (April 9, 1953, item 3158).

Having solved both problems that led him to shelve Sign and Object in 1946, it is perhaps no surprise that Quine considered breathing new life into his plan to write a philosophical monograph. In March 1952, Quine requests a small grant from the Harvard Foundation For Advanced Study and Research for secretarial assistance for a “book on semantics and theory of knowledge”, a book that “has been gradually evolving in connection with the course in Philosophy of Language which I have given several times in the past few years” (March 4, 1952, item 475). Two months later, Quine writes Roman Jakobson—the editor of the M.I.T. Press Studies in Communication Series—that he is thinking about a book entitled Language and Knowledge: “For years my thought has been evolving in the direction of such a book; and I have looked upon various of my articles, as well as my course on philosophy of language, as steps toward it” (May 18, 1952, item 1488).Footnote 46

9 Epilogue: Word and Object

In the end, it would take Quine seven more years to complete his first philosophical monograph. During these years, he was primarily concerned with the development of his genetic account; his study of “the relation of sensory stimulation to the production of scientific hypotheses by people” (April 9, 1953, item 3158). Where Quine’s first published attempt to develop such a genetic account—“The Scope and Language of Science” (1954)—still presents a sketchy story that focuses solely on ostension and internal similarity standards,Footnote 47Word and Object provides a detailed and complex account involving stimulus meanings, prelinguistic quality spaces, phonetic norms, discrimination thresholds, degrees of observationality, and observation sentences.Footnote 48

Burton Dreben, without doubt Quine’s closest philosophical companion, has aptly described Word and Object as “the mirror-image of Carnap’s philosophy”—as the book that “shows how Carnap is transformed once his most basic assumption is dropped, namely the fundamental distinction between philosophy and science, between the analytic and the synthetic” (1990, p. 88). In this paper, I have aimed to contribute to our understanding of the evolution of Quine’s thought between 1940, when he first set out to write a philosophical monograph, and the early 1950s, when he first felt ready to complete this project. Sign and Object, I have argued, sheds new light on the evolution of Quine’s ideas. The notes, letters, and manuscripts related to the project reveal that although Quine’s views were already surprisingly naturalistic in the early 1940s, two problems prevented him from developing a comprehensively naturalistic view on philosophical inquiry, problems he could only resolve in the early 1950s. Moreover, Sign and Object shows that Quine’s development should not only be understood in terms of his struggle with Carnap’s views about analyticity, eventually culminating in “Two Dogmas of Empiricism”. Both Carnap’s views on metaphysics and (Quine’s interpretation of) his views on epistemic priority have played a very substantial role in Quine’s development as well. Word and Object is one of the most influential works in the history of analytic philosophy because it offers a novel and comprehensively naturalistic perspective on language, metaphysics and epistemology. Sign and Object unearths the steps Quine had to take in developing this perspective.