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I will discuss four papers (Carnap 1950; Quine 1951; Friedman 2006; Price 1997) and their relation in this post. Friedman and Price expound on Carnap’s view and the discourse between Quine & Carnap; however, their scope of analysis goes beyond (Carnap 1950) and (Quine 1951). Therefore, I will divide the analysis into two pairs: (Carnap 1950 vs. Quine 1951) and (Friedman 2006 vs. Price 1997).

I will have two parts. First, I will outline each paper’s theses, arguments, and rebuttals (if any); the accuracy and clarity of the first part are central to providing any significance to the second part. Some of the papers’ arguments are presented as rebuttals to an objection. My second part will focus on how Friedman and Price contribute to reevaluating Carnap and Quine’s positions centered around (Carnap 1950) and (Quine 1951). I will conclude with the claim that Friedman’s interpretation of Carnap is essential in vindicating and appreciating Carnap’s contribution. 

Background and Key Concepts:

Empiricism: A philosophical theory that emphasizes the role of sensory experience in the formation of ideas, denying the notion of innate ideas or knowledge.

Synthetic vs. Analytic Statements: Analytic statements are true by virtue of meanings, independent of facts (e.g., “All bachelors are unmarried”), while synthetic statements depend on the way the world is (e.g., “The cat is on the mat”). This distinction is critical in understanding philosophical arguments about knowledge and truth, particularly in the dispute between Carnap and Quine, where Quine challenges the validity of this distinction.

Verification Theory of Meaning: A theory that the meaning of a proposition is synonymous with what empirical evidence would confirm or refute it.

Pragmatism: A philosophical approach that assesses the truth of beliefs and theories based on their practical applications and effectiveness. Both Carnap and Quine incorporate elements of pragmatism in their philosophies, emphasizing the practical utility of scientific and linguistic frameworks.

Carnap’s Internal and External Questions: Internal questions are about the existence of certain entities — constants or variables, within the framework governed by those linguistic rules, and they are answered by empirical or logical means; external questions are about the existence of the framework as a whole

Quine’s Critique of Analyticity: Quine’s argument that there is no clear distinction between analytic truths (true by language alone) and synthetic truths (true by how they conform to the world). This critique is central to the debates over whether certain foundational philosophical distinctions are valid. This can influence how we think about logic, mathematics, and science.

Carnap and Quine’s Views on Science and Mathematics: Carnap views science and mathematics through the lens of logical frameworks and conventions, whereas Quine sees them as part of a holistic system of empirical beliefs. This contrast influences their broader philosophical disagreements, particularly on the role of logic and empirical evidence in scientific practice.

Friedman’s and Price’s Historical and Exegetical Analyses: Both authors provide historical analyses of Carnap’s and Quine’s philosophical positions. Friedman focuses on their influences from Kant and Hume, while Price discusses the implications of their views on metaphysics.

Papers in this post:

Price, Huw “Carnap, Quine and the Fate of Metaphysics.”

Friedman, Michael. “Carnap and Quine: Twentieth-Century Echoes of Kant and Hume.”

Carnap, Rudolf. “Empiricism, Semantics, and Ontology.”

Quine, W. V. “Main Trends in Recent Philosophy: Two Dogmas of Empiricism.”

Paper Reconstruction: Friedman and Price on Quine & Carnap

Rudolf Carnap: (More in Detail)

Rudolf Carnap’s thesis in “Empiricism, Semantics, and Ontology” is that Linguistic frameworks with internal and external questions concerning the existence of entities are necessary for thinking about or introducing entities within the framework without ontologically committing to them (in terms of Realism), and we ought to adopt frameworks based on pragmatic concerns.

Carnap’s argument rests on explaining how the language of entities, including abstraction, is possible without committing to their metaphysical reality. He does this by distinguishing between internal and external questions regarding a framework or a linguistic system. Internal questions are about the existence of certain entities — constants or variables, within the framework governed by those linguistic rules, and they are answered by empirical or logical means; external questions are about the existence of the framework as a whole (Carnap 1950, 2). After defining a framework, Carnap provides examples of various frameworks, for instance, the system of propositions or the spatio-temporal coordinate system for physics, to show how we may construct and use them and that speaking of abstraction like numbers need not assert or assume a metaphysical position. 

Carnap explicitly rebuts an objection asserting that one must commit to some reality of entities before using them in a language. He holds that using a framework does not imply an assertion of reality; therefore, it needs no theoretical justification for its use (Carnap 1950, 7). Moreover, he argues that we are justified in holding external questions as pseudo-questions because there is no sufficient cognitive content to comprehend nor answer the question in the metaphysical sense (Carnap 1950, 4). Other empiricists object that abstract concepts like “red” should not designate anything real in the empiricist system because doing so commits one to its metaphysical reality (Carnap 1950, 7 – 8). In response to the semantic objections, Carnap emphasizes that many statements involving abstract entities are analytic within their respective frameworks. In other words, they are true under linguistic rules rather than empirical verification, and the reference is within the framework, not external entities (Carnap 1950, 8 – 9). 

W.V. Quine: (More in detail)

In “Two Dogmas of Empiricism,” W.V. Quine presents two theses. First, there is no fundamental distinction between analytic statements, true in virtue of meaning independent of matter of fact, and synthetic statements, true based on matter of fact. In defense of the first thesis, he shows that analyticity in terms of meaning, synonymy, definition, or semantic rule fails to capture what analyticity is to the thinker. The second thesis is the following: Meaningful statements cannot be reduced to terms that refer to immediate experience. Here, I will not discuss Quine’s pragmatism. 

Quine argues that analyticity, understood as a definition, is inadequate because it is grounded in contingent pre-existing language use. He acknowledges that there are definitions given at the moment of composition that do not rely on pre-existing use. Still, he argues that natural language involves practical expressions that sacrifice economy in grammar and vocabulary (Quine 1951, 26 – 7). Therefore, natural language does not consist of precise definitions that do not rely on pre-existing use. In addition, he claims that definitions in natural languages presuppose pre-existing synonymies, which makes explanation by definition circular and fails to independently refer to the meaning of terms (Quine 1951, 25). He then turns to assess interchangeability salva veritate, where interchanging synonyms preserve the truth value of a sentence (Quine 1951, 28). He objects that interchangeability is insufficient for synonymy because it does not necessarily preserve truth value and meaning across every context. Against the ‘analytic’ as true according to semantic rule, Quine argues that semantic rule is similarly meaningless like the ‘analytic’ because semantic rules are contingent postulates; it fails to capture the ‘necessity’ that seems to be a part of analytic statements (Quine 1951, 33). Quine sees these semantic rules as not clarifying the concept of analyticity because they presuppose an understanding of the ‘analytic’ they are supposed to explain. He concludes that, as shown in the rejection of analyticity in terms of meaning, synonymy, definition, or semantic rule, the synthetic-analytic distinction is untenable because it must rely on other unclear or circular concepts.

Regarding the second thesis, Quine explains that the verification theory of meaning holds that statements are synonymous iff statements are verified using a similar empirical confirmation or invalidation method. In this view, an analytic statement is defined as one that is confirmable regardless of the empirical conditions (Quine 1951, 35). He criticizes the verification theory and reduction of statements in terms of immediate experience because of their vague and impractical methodology (Quine 1951, 36); therefore, one cannot establish the analytic-synthetic distinction through the preceding means either. 

Michael Friedman:

In “Carnap and Quine: Twentieth-Century Echoes of Kant and Hume,” Michael Friedman takes a historical approach using textual evidence to elucidate Carnap’s evolving view and how it differs from Quine’s. The main thesis is that Carnap differentiates his Empiricism from Quine’s by maintaining a synthetic-analytic distinction where factual contentless logico-mathematical contents function as a prior structuring that enables empirical science. Another closely related sub-thesis is that Quine misunderstands Carnap’s Empiricism. According to Friedman, Carnap and Quine have different influences: While both diverge in their unique views, the former has a Kantian influence, while the latter has a Humean influence (Friedman 2006, 42 – 3). Different influences led Quine to believe in a holistic epistemology without a synthetic-analytic distinction, while Carnap believed in the role of the ‘analytic’ in scientific practice.

While Friedman does not state explicitly, Quine appears to misconstrue the goals and methods of Carnap’s philosophical project; Carnap did not intend to justify logico-mathematical content as objective truth but to use it as a formal role that guides empirical science (Friedman 2006, 36). Moreover, despite the significant role of the principle of tolerance, Quine misapprehends it (Friedman 2006,  39). One objection Friedman raises concerns the potential circularity of the principle of tolerance and how one cannot understand one mathematical framework in terms of another (Friedman 2006, 38). He rebuts that one can begin with a framework (e.g., classical) and modify it gradually, incorporating elements of other systems (e.g., intuitionist) to arrive at a different framework (Friedman 2006, 38). Therefore, the principle of tolerance does not beg the question against other systems, and it shows that one can revise the analytic part of a framework. Quine objects to the distinction between the L and P rules being arbitrary (Friedman 2006,  48). In response to the objection and for his thesis, Friedman shows that Carnap held that a distinction “is indispensable for the logical analysis of science;” therefore,  it is not arbitrary (Friedman 2006, 50).

Through textual evidence, Friedman has argued the following: Carnap is not arguing for mathematical certainty; he believes there are no external questions about the truth about mathematical Realism. There is mathematical certainty within the internal question, but this internal system can be revised. More importantly, he is saying that there is certainty in the structure of science. One is logical (whether one adopts intuitionist, classical mathematics, etc) without factual content, and the other is empirical with factual content. Since Quine did not see Carnap’s position, he inadequately criticized Carnap’s synthetic-analytic distinction in his Empiricism. 

Huw Price:

In “Carnap, Quine and the Fate of Metaphysics,” Huw Price argues that Carnap implicitly held (while Quine implicitly denies) an ontological pluralism in which each framework has an independent quantifier over its entities and that internal-external distinction remains central, contrary to Quine’s criticism. 

Price supports his interpretation of Carnap’s view in the following way. If one is outside the framework, one cannot understand its content and rules; one can only judge its functional utility from the outside. He also claims that one cannot simultaneously be inside and outside a framework or language (Price 1997, 9, 11). Quine agrees with the preceding point (Price 1997, 15). However, frameworks can have different quantifiers, not because access to the rules and semantics of the framework’s internal question is limited to those who have adopted the framework. There are different senses of quantifiers due to the functional nature of language where the comparison of two entities does not make sense due to their difference in their domains, as discussed by Ryle (Price 1997, 10, 18-9). This illuminates the role of internal-external distinction.

Quine objects that internal-external distinction is illegitimate because the analytic-synthetic distinction is unjustified. If the analytic-synthetic distinction does not exist, all matters will be under pragmatic concerns without purely internal questions. Additionally, if there is no internal-external distinction, there is no basis to distinguish concepts into independent frameworks (Price 1997, 7-8, 14-5). Price defends by undermining the relevancy of the analytic-synthetic discourse in establishing the internal-external distinction (Price 1997, 9). While analytic-synthetic distinction exists in each framework as an internal question (Price 1997, 7), frameworks function independently due to separate quantifiers. He explains that ontological pluralism is built on the functional aspects of languages so that internal-external distinction can be maintained, even if Quine is right about the baselessness of analytic-synthetic distinction (Price 1997, 19-20).

According to Price, one of Carnp’s positions is that language use ontologically commits us to entities within the language. There is an objection that  people speaking of ‘dragons’ do not seem to commit to the existence of ‘dragons.’  Price states that ontological commitment means following the rules of the framework and that it does not commit one to Realism when speaking of the entities (Price 1997, 13). For instance, the internal question, “Does a dragon exist?” could yield true or false depending on the framework.

A Critical Note: Synthesis

Friedman and Price’s scope of analysis goes beyond Carnap 1950 and Quine 1951. Therefore, let us first restrict the analysis to the comparison between 1950 and Quine 1951 before comparing Friedman and Price’s papers. 

Carnap and Quine are empiricists trying to provide a better account of Empiricism; they agree on a few ontological matters. For instance, they agree that a reductive account of the verification theory regarding sense data is untenable (Carnap 1950, 12 and Quine 1951, 36). They recognize the limitations of traditional empiricist approaches (e.g., Hume or Locke) that strictly confine meaningful statements to empirical verifiability. As seen in footnote 3, Carnaps states that Quine has introduced the idea that entities in the framework are a value of a variable of the framework: Carnap adopts this idea. Moreover, both agree about the role of pragmatism in constructing their respective systems. The overlapping scope between Carnap and Quine revolves around their emphasis on the role of linguistic construction in shaping and understanding empirical knowledge; however, they disagree on how one ought to construct it. Since the subject matter is the same — linguistic constructions, the two positions can be placed on a single dialectical spectrum; the placement depends on how holistic or rigid the construction requirements are. 

Carnap and Quine disagree on whether there is a clear distinction between the analytic and the synthetic. The former says yes, and the latter says no. In footnote 5, Carnap states that Quine does not acknowledge the distinction between internal and external questions because he maintains that “there are no sharp lines between logical and factual truth… between the acceptance of a language structure and the acceptance of an assertion formulated in the language”(Carnap 1950, 12). Furthermore, Carnap provides a positive argument while criticizing Realism and nominalism. However, he does not directly criticize Quine’s views. On the other hand, Quine directly addresses Carnap’s position when criticizing semantical rules for merely postulating the ‘analytic’ without explaining it (Quine 1951, 32). While Carnap maintains many frameworks like the system of propositions, the system of thing properties, etc., Quine operates under a single framework or a web of belief. 

Let us turn to Friedman and Price’s papers. Neither of their papers references each other’s work. Still, we may consider the compatibility of the papers’ arguments. According to Friedman, the framework of mathematics (classical, intuitionist, etc.) requires a gradual change of the internal rules and entities if one wants to shift from classical to intuitionist mathematics and vice versa (Friedman 2006, 38). This suggests that we cannot simultaneously hold multiple independent mathematical frameworks. However, the preceding does not preclude one from holding a framework, for instance, about the properties of objects, simultaneously with a mathematical framework because they concern different domains. The preceding conclusion agrees with Price’s interpretation of framework pluralism, which holds that frameworks have separate quantifiers by virtue of residing in fundamentally different domains. Since intuitionist and classical mathematics are in the same domain and thus commensurable, they are discussed under a single framework with the same quantifier. In contrast, classical mathematics and the phenomenal properties of objects require separate, independent frameworks where elements of the former cannot be compared to elements belonging to the latter. In other words, Friedman does not consider what Price is arguing for, but there is nothing contradictory between the two interpretations. Still, this does not mean that Friedman has endorsed Prices’s interpretation. 

Both authors agree about the existence of the analytic-synthetic distinction. They also agree with Carnap’s anti-metaphysical approach, which regards metaphysical statements (external questions) as devoid of empirical content and, therefore, non-cognitive. Price does not expound on the nature of the analytic-synthetic distinction, but Friedman sharpens its role and significance in Carnap’s system. He shows that Carnap tried to defend ‘analyticity’ against Quine’s criticism through semantic rules intertwined with the logical structure of languages that become the basis for modern sciences. However, Price implies that analytic-synthetic distinction is unnecessary to maintain Carnap’s external-internal distinction and framework pluralism (Price 1997, 20). Still, Friedman would object to Price’s implications about the place of the analytic-synthetic distinction. 

While Friedman does not explicitly state the following, he implies that frameworks will lack pragmatic merits without the factually contentless logico-mathematical component of the internal questions. A set of factual content without rules or relation to one another seems useless. If Friedman’s explication of analytic-synthetic distinction is correct, the analytic-synthetic distinction is necessary for pragmatic reasons alone, which is a pressing criticism against Quine. As Friedman argues, Carnap is concerned with providing the tools for modern science (Friedman 2006, 50). In support of the preceding, Carnap states, “The acceptance or rejection of linguistic forms [in all science,]will finally be decided by their efficiency as instruments, the ratio of the results achieved to the amount and complexity of efforts required” (Carnap 1950, 11). 

Regarding pragmatism, for instance, a framework with a variable of letters (referring to graphemes, not phonemes) without the rules for putting those letters to form words lacks utility. However, the example shows that a framework is devoid of the factually contentless component. This means that the framework can exist without the analytic-synthetic distinction. Carnap holds that while we implicitly adopt the thing language, we may refuse to adopt it by, for instance, refraining from speaking (Carnap 1950, 2). Therefore, Price’s interpretation augments Friedman’s interpretation and vice versa. Both interpretations may remain vulnerable to Quine’s criticism when it stands alone. 


I have discussed philosophical dialogues between Carnap and Quine, which Friedman and Price have expanded upon. I have written that Friedman and Price’s interpretations may remain vulnerable to Quine’s criticism when they stand alone. Nevertheless, I conclude that Friedman’s interpretation is more resilient than Price’s interpretation against Quine’s criticism. This is because any practical framework has an analytic-synthetic distinction. Even for Quine’s web of belief to be useful, it must contain the analytic part that provides the rules for its factual contents, regardless of the malleability of those rules. When Price’s interpretation, framework pluralism by quantifiers, stands alone without the analytic-synthetic distinction of Friedman’s interpretation, one is left with many frameworks with only factual content. Even if one has many frameworks, they are useless without factual, contentless rules. Finally, when we evaluate exegetically, Friedman’s interpretation emerges stronger primarily for its textual support. Nonetheless, Price’s paper is a valuable contribution to metaphysics and further augments Carnap’s system.



  • Carnap, Rudolf. “Empiricism, Semantics, and Ontology.” Revue Internationale de Philosophie, vol. 4, no. 11, (1950): 20–40.
  • Friedman, Michael. “Carnap and Quine: Twentieth-Century Echoes of Kant and Hume.” Philosophical topics 34, no. 1/2 (2006): 35–58.
  • Price, Huw. “Carnap, Quine and the Fate of Metaphysics.” Electronic Journal of Analytic Philosophy 5 no.1 (1997).
  • Quine, W. V. “Main Trends in Recent Philosophy: Two Dogmas of Empiricism.” The Philosophical Review 60, no. 1 (1951): 20–43.

*Disclaimer: This article is a creative interpretation and synthesis work, drawing inspiration from multiple sources. While efforts have been made to ensure the accuracy of the information presented, readers are encouraged to consult the source material for a comprehensive understanding.

**Please note that I often write the Critical Note (constructive criticism) section after posting the article. If the section is left blank, it is intentional.

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