The main task in this paper is to detail and investigate Carnap’s conception of a “linguistic framework”. On this basis, we will see whether Carnap’s dichotomies, such as the analytic-synthetic distinction, are to be construed as absolute/fundamental dichotomies or merely as relative dichotomies. I argue for a novel interpretation of Carnap’s conception of a LF and, on that basis, will show that, according to Carnap, all the dichotomies to be discussed are relative dichotomies; they depend on conventional decisions concerning (...) the logical syntax of LF. Thus, all of the dichotomies directly hinge on the conception of the LF. The LF’s logical structure, in turn, is an immediate consequence of adopting the linguistic doctrine of logical truths. As we will see, no appeal to any of these distinctions is necessary in establishing a LF and all of its components. I will also draw attention to the differences between what Carnap labels a “way of speaking”, “language”, and “artificial language”. Consequently, I will briefly conclude that none of Quine’s major objections address the main points of Carnap’s theory. (shrink)

In this paper, I defend Rudolf Carnap's Principle of Tolerance from an accusation, due to Michael Friedman, that it is self-defeating by prejudicing any debate towards the logically stronger theory. In particular, Friedman attempts to show that Carnap's reconstruction of the debate between classicists and intuitionists over the foundations of mathematics in his book The Logical Syntax of Language, is biased towards the classical standpoint since the metalanguage he constructs to adjudicate between the rival positions is fully classical. (...) I argue that this criticism is mistaken on two counts: (1) it fails to fully appreciate the freedom with regard to the construction of linguistic frameworks that Carnap intended his Principle to embody, and (2) Friedman's objection underestimates the extent to which the evaluation of a framework is task-relative. I conclude that Tolerance is not self-undermining in the way that Friedman claims it is. While this is a restricted conclusion -- and is not a vindication of Carnap's views on logic and mathematics tout court -- it nonetheless suggests that his tolerant perspective has been dismissed too quickly, even by his supporters. (shrink)

According to general wisdom, Carnap's quasianalysis is an ingenious but definitively flawed approach to epistemology and philosophy of science. I argue that this assessment is mistaken. Rather, Carnapian quasianalysis can be reconstructed as a special case of a general theory of structural representation. This enables us to exploit some interesting analogies of quasianalysis with the representational theory of measurement. It is shown how Goodman's well-known objections against the quasianalytical approach may be defused in the new framework. As an (...) application, I sketch how the thesis of empirical underdetermination of theories may be elucidated in the framework of quasianalysis. (shrink)

In his seminal work “The Concept of Truth in Formalized Languages”, Alfred Tarski showed how to construct a formally correct and materially adequate definition of true sentence for certain formalized languages. These results have, eventually, been accepted and applauded by philosophers and logicians nearly in unison. Its Postscript, written two years later, however, has given rise to a considerable amount of controversy. There is an ongoing debate on what Tarski really said in the postscript. These discussions often regard Tarski as (...) putatively changing his logical framework from type theory to set theory. In what follows, we will compare the original results with those presented two years later. After a brief outline of Carnap’s program in The Logical Syntax of Language we will determine its significance for Tarski’s final results. (shrink)

In Der logische Aufbau der Welt, first published in 1928, Carnap aims to rationally reconstruct all objects of cognition by logico-definitional means. As a result, he intends to obtain a fully objective framework in which scientific discourse can take place. This is made possible by the novel method of ‘purely structural definite description’ of all scientifically relevant objects, which is first introduced in the Aufbau. Key to the attainment of this goal is the notion of ‘foundedness’, which Carnap presents (...) as a new basic notion of logic, in order to establish a link between the purely conventional world of logical and mathematical knowledge and the empirical world of knowledge of scientific objects. This idea experienced major criticism by Friedman (1999a,b) since he considers it to lead to the demolition of the boundary between those two worlds. In this essay, we want to defend foundedness against Friedman’s critique by arguing that its introduction is necessary within Carnap’s logicist world of thought to deal with a more fundamental problem: the demarcation of the empirical parts of the Aufbau. In the last section, we will give an outlook on the actual cause for the failure of the Aufbau, the lack of a principle to determine the truth of the instances of the basic relation in the Aufbau, and we will show how this can contribute to the explanation of Carnap’s future philosophical development and retrospective self-evaluation. This essay serves as a dense informal sketch for a later extensive formal treatment of this reading of foundedness and focuses on its implications for the interpretation of Carnap’s post-Aufbau development. (shrink)

This paper presents an overview of Carnap, a free and open framework for the development of formal reasoning applications. Carnap’s design emphasizes flexibility, extensibility, and rapid prototyping. Carnap-based applications are written in Haskell, but can be compiled to JavaScript to run in standard web browsers. This combination of features makes Carnap ideally suited for educational applications, where ease-of-use is crucial for students and adaptability to different teaching strategies and classroom needs is crucial for instructors. The paper describes Carnap’s implementation, (...) along with its current and projected pedagogical applications. (shrink)

Several recent works in history and philosophy of science have re-evaluated the alleged opposition between the theses put forth by logical empiricists such as Carnap and the so-called "post-positivists", such as Kuhn. Although the latter came to be viewed as having seriously challenged the logical positivist views of science, recent authors (e.g., Friedman, Reisch, Earman, Irzik and Grünberg) maintain that some of the most notable theses of the Kuhnian view of science have striking similarities with some aspects of Carnap's (...) philosophy. Against that reading, Oliveira and Psillos argue that within Carnap's philosophy there is no place for the Kuhnian theses of incommensurability, holism, and theory-ladenness of observations. This paper presents each of those readings and argues that Carnap and Kuhn have non-opposing views on holism, incommensurability, the theory-ladenness of observations, and scientific revolutions. We note at the very end - without dwelling on the point, however - that they come apart on other matters, such as their views on metaphysics and on the context of discovery/justification distinction. (shrink)

Forthcoming in Darren Bradley (ed.), Carnap and Contemporary Philosophy. -/- This paper is centered on Carnap’s views on rationality. More specifically, much of the focus is on a puzzle regarding Carnap’s view on rationality that Florian Steinberger has recently discussed. Not only is Steinberger’s discussion of significant intrinsic interest: his discussion also raises general questions about Carnap interpretation. As I have discussed in earlier work, there are two very different ways of interpreting Carnap’s talk of “frameworks” – and, relatedly, different (...) ways of interpreting Carnap’s principle of tolerance. Carnap can be interpreted as either a relativist or as what I call a language pluralist. Steinberger’s puzzle arises given the relativist interpretation; I believe the language pluralist interpretation is correct. Most of the discussion will concern the correct interpretation of Carnap, and what this means for Steinberger’s puzzle. While I will not here mount a full defense of the language pluralist interpretation, I will pause to discuss Vera Flocke’s recent criticism of it. Towards the end, I will describe a puzzle regarding rationality different from Steinberger’s. The puzzle that I describe does arise already for the language pluralist. (shrink)

A. W. Carus champions Rudolf Carnap’s ideal of explication as a model for liberal political deliberation. Constructing a linguistic framework for discussing social problems, he argues, promotes the resolution of our disputes. To flesh out and assess this proposal, I examine debate about the social institutions of marriage and adoption. Against Carus, I argue that not all citizens would accept the pragmatic principles underlying Carnap’s ideal. Nevertheless, explication may facilitate inquiry in the social sciences and be used to create (...) models that help us to understand past disputes. This latter application reveals explication’s potential for refining the social histories that inform contemporary political discourse. (shrink)

Carnap’s seminal ‘Empiricism, Semantics and Ontology’ makes important use of the notion of a framework and the related distinction between internal and external questions. But what exactly is a framework? And what role does the internal/external distinction play in Carnap’s metaontology? In an influential series of papers, Matti Eklund has recently defended a bracingly straightforward interpretation: A Carnapian framework, Eklund says, is just a natural language. To ask an internal question, then, is just to ask a question (...) in, say, English. To try to ask an external question is to try, absurdly, to ask a question in no language at all. Finding that so trivial an I/e distinction can’t help to explain Carnap’s deflationary metaontology, Eklund is led to attribute to Carnap a view he calls ontological pluralism. In this paper, I show that Eklund misreads Carnap, and I argue that this misreading obscures fundamental features of Carnap’s philosophy. I then defend an account of frameworks as what Carnap called semantical systems, and I place this account in the context of Carnap’s philosophical program of explication. Finally, I discuss the role that frameworks and the I/e distinction play in ESO, showing that ESO provides no reason to attribute the doctrine of ontological pluralism to Carnap. (shrink)

In his recent article "Carnapian Frameworks" (Synthese, 2021), Gabriel Broughton criticizes my discussions of Carnap on ontology and puts forward his own interpretation of what Carnap’s external/internal distinction amounts to. I here first argue that Broughton’s main claims about me are based on a misinterpretation. Then I turn to some issues of broader interest. I argue that Broughton’s own, potentially interesting interpretation of Carnap’s external/internal distinction does not work. And in light of Broughton’s discussion I present a sharpened version of (...) what I have earlier said about Carnap’s this distinction. (shrink)

This paper examines Rudolf Carnap’s "Empiricism, Semantics, and Ontology," focusing on his pragmatic and deflationary approach to metaphysics. Key to Carnap’s view is the distinction between internal and external questions, which supports his linguistic pluralism and contextualism. I argue that Carnap’s ideas offer valuable insights for contemporary debates. Additionally, I assess the reception of Carnap’s work, particularly addressing W.V.O. Quine’s critiques. Despite their influence, I contend that Quine’s objections lack substantial grounding. This analysis reaffirms the relevance of Carnap’s contributions to (...) modern analytic philosophy, against the apparent flowering of the ontological and metaphysical questions in this philosophical current. (shrink)

I modify and generalize Carnap’s notion of frameworks as a way of unpacking Goodman’s metaphor of “making worlds with symbols”. My frameworks provide, metaphorically, a way of making worlds out of symbols in as much as all our framework-bound access to the world is through frameworks that always stand to be improved in accuracy, precision, and usually both. Such improvement is characterized in pragmatist terms.

Can the abstract entities be designated? While the empiricists usually took the positive answer to this question as the first step toward Platonism, in his ``Empiricism, Semantics, and Ontology’’ [Carnap 1950], Carnap tried to make a reconciliation between the language referring to abstract entities on the one hand, and empiricism on the other. In this paper, firstly, I show that the ingenuity of Carnap’s approach notwithstanding, it is prone to criticism from different aspects. But I also show how, even without (...) leaving the empiricist research program, the shortcomings could be amended. Following Carnap’s 1950 outset, and adding some apparently untasteful (Meinongian) ingredients, I will sketch a refined way for dealing with the problem of existence of abstract entities within the framework of the philosophy of empiricism. (shrink)

Carnap's conception of linguistic frameworks is widespread; however, it is not entirely clear nor consensual to pinpoint what is the influence of his stance within the traditional realist/anti-realist debate. In this paper, we place Carnap as a proponent of a scientific realist stance, by presenting what he called “linguistic realism”. Some possible criticisms are considered, and a case study is offered with wave function realism, a popular position in the philosophy of quantum mechanics.

A. J. Ayer’s Language, Truth, and Logic had been responsible for introducing the Vienna Circle’s ideas, developed within a Germanophone framework, to an Anglophone readership. Inevitably, this migration from one context to another resulted in the alteration of some of the concepts being transmitted. Such alterations have served to facilitate a number of false impressions of Logical Empiricism from which recent scholarship still tries to recover. In this paper, I will attempt to point to the ways in which LTL (...) has helped to foster the various mistaken stereotypes about Logical Empiricism which were combined into the received view. I will begin by examining Ayer’s all too brief presentation of an Anglocentric lineage for his ideas. This lineage, as we shall see, simply omits the major 19th century Germanophone influences on the rise of analytic philosophy. The Germanophone ideas he presents are selectively introduced into an Anglophone context, and directed towards various concerns that arose within that context. I will focus on the differences between Carnap’s version of the overcoming of metaphysics, and Ayer’s reconfiguration into what he calls the elimination of metaphysics. Having discussed the above, I will very briefly outline the consequences that Ayer’s radicalisation of the Vienna Circle’s doctrines had on the subsequent Anglophone reception of Logical Empiricism. (shrink)

Carnap's theory of descriptions was restricted in two ways. First, the descriptive conditions had to be non-modal. Second, only primitive predicates or the identity predicate could be used to predicate something of the descriptum . The motivating reasons for these two restrictions that can be found in the literature will be critically discussed. Both restrictions can be relaxed, but Carnap's theory can still be blamed for not dealing adequately with improper descriptions.

Everyone knows what David Lewis' possible worlds are, what role they play in his account of possibility and necessity, and Saul Kripke's criticisms. But what, instead, are Kripke's possible worlds, and what role do they play in his account of possibility and necessity? The answers are not so obvious. Recently, it has even been claimed that, contrary to what is standardly assumed, Kripke's approach to modality has not always been consistently metaphysical. In particular, an interpretation of the famous passage in (...) the preface to Naming and Necessity with Kripke's discussion of the dice example has been put forward, according to which he purports there to clarify the modal notions in terms of that of possible world, model-theoretically construed, in a way which is reminiscent of Carnap's. In this paper, I shall point out some internal difficulties of this interpretation, and offer a different one, according to which in the dice passage Kripke is trying, consistently with his metaphysical approach, to legitimize the technically useful notion of possible world starting from modal notions, to be accounted for in another way (arguably, in an essentialistic framework). My final goal, however, will be philosophical elucidation rather than mere exegesis. Indeed, I am interested in shedding some light on what possible worlds might possibly be, if something like Kripke's metaphysical approach is on the right track. (shrink)

In this article, I draw an important distinction between two kinds of inquiry. “Framed inquiries” take for granted and use a conceptual framework in order to ask and answer questions, while “framing inquiries” require the creation, revision, or expansion of the conceptual framework itself in order to address the problem at hand. This distinction has been largely ignored in epistemology, and collapsed by two radically opposed philosophical camps: representationalism and antirepresentationalism. While the former takes all inquiries to be (...) in the business of discovering mind-independent facts, the latter takes all inquiries to be primarily governed by pragmatic considerations. Against the objections raised by both camps, I defend a pragmatist and substantive distinction between framed and framing inquiry, inspired by Rudolf Carnap’s distinction between internal and external questions and reformulated in terms of John Dewey’s theory of inquiry. (shrink)

W. V. Quine famously defended two theses that have fallen rather dramatically out of fashion. The first is that intensions are “creatures of darkness” that ultimately have no place in respectable philosophical circles, owing primarily to their lack of rigorous identity conditions. However, although he was thoroughly familiar with Carnap’s foundational studies in what would become known as possible world semantics, it likely wouldn’t yet have been apparent to Quine that he was fighting a losing battle against intensions, due in (...) large measure to developments stemming from Carnap’s studies and culminating in the work of Kripke, Hintikka, and Bayart. These developments undermined Quine’s crusade against intensions on two fronts. First, in the context of possible world semantics, intensions could after all be given rigorous identity conditions by defining them (in the simplest case) as functions from worlds to appropriate extensions, a fact exploited to powerful and influential effect in logic and linguistics by the likes of Kaplan, Montague, Lewis, and Cresswell. Second, the rise of possible world semantics fueled a strong resurgence of metaphysics in contemporary analytic philosophy that saw properties and propositions widely, fruitfully, and unabashedly adopted as ontological primitives in their own right. This resurgence — happily, in my view — continues into the present day. -/- For a time, at any rate, Quine experienced somewhat better success with his second thesis: that higher-order logic is, at worst, confused and, at best, a quirky notational alternative to standard first-order logic. However, Quine notwithstanding, a great deal of recent work in formal metaphysics transpires in a higher-order logical framework in which properties and propositions fall into an infinite hierarchy of types of (at least) every finite order. Initially, the most philosophically compelling reason for embracing such a framework since Russell first proposed his simple theory of types was simply that it provides a relatively natural explanation of the paradoxes. However, since the seminal work of Prior there has been a growing trend to consider higher-order logic to be the most philosophically natural framework for metaphysical inquiry, many of the contributors to this volume being among the most important and influential advocates of this view. Indeed, this is now quite arguably the dominant view among formal metaphysicians. -/- In this paper, and against the current tide, I will argue in §1 that there are still good reasons to think that Quine’s second battle is not yet lost and that the correct framework for logic is first-order and type-free — properties and propositions, logically speaking, are just individuals among others in a single domain of quantification — and that it arises naturally out of our most basic logical and semantical intuitions. The data I will draw upon are not new and are well-known to contemporary higher-order metaphysicians. However, I will try to defend my thesis in what I believe is a novel way by suggesting that these basic intuitions ground a reasonable distinction between “pure” logic and non-logical theory, and that Russell-style semantic paradoxes of truth and exemplification arise only when we move beyond the purely logical and, hence, do not of themselves provide any strong objection to a type-free conception of properties and propositions. -/- Most of my arguments in §1 are largely independent of any specific account of the nature of properties and propositions beyond their type-freedom. However, I will in addition argue that there are good reasons to take propositions, at least, to be very fine-grained. My arguments are thus bolstered significantly if it can be shown that there are in fact well-defined examples of logics that are not only type-free but which comport with such a conception of propositions. It is the purpose of §2 to lay out a logic of this sort in some detail, drawing especially upon work by George Bealer and related work of my own. With the logic in place, it will be possible to generalize the line of argument noted above regarding Russell-style paradoxes and, in §3, apply it to two propositional paradoxes — the Prior-Kaplan paradox and the Russell-Myhill paradox — that are often taken to threaten the sort of account developed here. (shrink)

A brief review of Carnap's formal program in philosophy of science.

Which premisses should we use to start our inquiries? Which transitions during inquiry should we take next? When should we switch lines of inquiry? In this paper, I address these open questions about inquiry, formulating novel norms for such decisions during deductive reasoning. I use the first-order predicate calculus, in combination with Carnap’s state description framework, to state such norms. Using that framework, I first demonstrate some properties of sets of sentences used in deduction. I then state some (...) norms for decisions made during deductive reasoning, establishing initial benchmarks for efficient deduction by ideal reasoners. When deciding which transition to make next, reasoners should choose the most informative transition, the one that maximally reduces uncertainty in the sense of ruling out the largest number of state descriptions relevant to their inquiry. Finally, inspired by optimal foraging theory, I show that, under certain assumptions of ignorance, reasoners should change premiss sets when their information intake drops below the global average information intake across premiss sets. (shrink)

Logic is about reasoning, or so the story goes. This thesis looks at the concept of logic, what it is, and what claims of correctness of logics amount to. The concept of logic is not a settled matter, and has not been throughout the history of it as a notion. Tools from conceptual analysis aid in this historical venture. Once the unsettledness of logic is established we see the repercussions in current debates in the philosophy of logic. Much of the (...) battle over the ‘one true logic’ is conceptually talking past each other. The theory of logics-as-formalizations is presented as a conceptually open theory of logic which is Carnapian in flavour and grounding. Rudolf Carnap’s notions surrounding ‘external’ and ‘pseudo-questions’ about linguistic frameworks apply to formalizations, thus logics, as well. An account of what formalizations are, a more structured sub-set of modelling, is given to ground the claim that logics are formalizations. Finally, a novel account of correctness, the COFE framework, is developed which allows the notions of logical monism, pluralism and nihilism to be more precisely formulated than they currently are in the discourse. (shrink)

Many who take a dismissive attitude towards metaphysics trace their view back to Carnap’s ‘Empiricism, Semantics and Ontology’. But the reason Carnap takes a dismissive attitude to metaphysics is a matter of controversy. I will argue that no reason is given in ‘Empiricism, Semantics and Ontology’, and this is because his reason for rejecting metaphysical debates was given in ‘Pseudo-Problems in Philosophy’. The argument there assumes verificationism, but I will argue that his argument survives the rejection of verificationism. The root (...) of his argument is the claim that metaphysical statements cannot be justified; the point is epistemic, not semantic. I will argue that this remains a powerful challenge to metaphysics that has yet to be adequately answered. (shrink)

Even after Willard Quine’s critique of the analytic-synthetic distinction in “Two Dogmas of Empiricism,” Wilfrid Sellars maintained some forms of analyticity or truth in virtue of meaning. In this article, I aim to reconstruct (a) his neglected account of the analytic-synthetic distinction and the revisability of analytic sentences, (b) its connection to his inferentialist account of meaning, and (c) his response to Quine. While Sellars’s account of the revisability of analytic sentences bears certain similarities to Carnap’s and Grice and Strawson’s (...) accounts, it is still striking in that it is part of his broader picture of how our language develops dynamically in our ongoing inquiry. I aim to show how it relates to his account of how the diachronic continuity in meaning, language, or conceptual framework can be preserved through a revision of analytic sentences and to his evolutionary account of the development of our language or conceptual framework. (shrink)

This is what I hope is an illuminating, and to a certain degree, novel exposition of Montague Grammar. It is against many standard interpretations, and perhaps even against things Montague himself says at times. However, it makes more sense of how his various commitments fit together in a systematic way. Why, for instance, is it called "Montague Grammar" rather than "Montague Semantics," and what role does his commitment to Fregeanism plays in his conception of language? It is clear that he (...) is committed to the idea that function application is the fundamental mode of semantic composition, and that he is committed to an intensional framework. However, intensions have, since Carnap, been understood as nearly conceptually equivalent to functions from possible worlds to sets of individuals. But, in truth, possible worlds semantics is just dressed up extensional semantics. There are just more objects to go around to serve as inputs for functions, whatever we think of their ontological status. That is, possible worlds semantics is really a semantic reduction of intensional semantics achieved by expanding our ontological commitments. It would be difficult to make sense of Montague's strong commitment to Fregean semantics, if his notion of intension was that of Carnap's. According to my interpretation, Montague's notion of intension must be distinct from the version adopted by possible world semantics. Montague took seriously the idea that intensional semantics was something quite different from extensionalist semantics. The first was not reducible to the second semantically speaking. Just as Frege believed that meaning consisted of both sense and reference, so too did Montague. However, just as Frege also believed, Montague thought that sense and reference were systematically related. As I illustrate, interpreting Montague as adopting a different notion of intension can also resolve the apparent problem of distinguishing the difference in meaning between intensional equivalents. It might also enable us to draw a distinction in epistemic logic between an agent having contradictory beliefs and believing contradictions. (shrink)

Quine’s classical classic interpretation succinctly characterized characterizes Carnap’s Aufbau as an attempt “to account for the external world as a logical construct of sense-data....” Consequently, “Russell” was characterized as the most important influence on the Aufbau. Those times have passed. Formulating a comprehensive and balanced interpretation of the Aufbau has turned out to be a difficult task and one that must take into account several disjointed sources. My thesis is that the core of the Aufbau rested on a problem that (...) had haunted German philosophy since the end of the 19th century. In terms fashionable at the time, this problem may be expressed as the polarity between Leben and Geist that characterized German philosophy during the years of the Weimar Republic. At that time, many philosophers, including Cassirer, Rickert and Vaihinger, were engaged in overcoming this polarity. As I will show, Carnap’s Aufbau joined the ranks of these projects. This suggests that Lebensphilosophie and Rickert’s System der Philosophie exerted a strong influence on Carnap’s projects, an influence that is particularly conspicuous in his unpublished manuscript Vom Chaos zur Wirklichkeit. Carnap himself asserted that this manuscript could be considered “the germ of the constitution theory” of the Aufbau. Reading Chaos also reveals another strong but neglected influence on the Aufbau, namely a specific version of neutral monism put forward by the philosopher and psychologist Theodor Ziehen before World War I. Ziehen’s work contributed much to the invention of the constitutional method of quasi-analysis. -/-. (shrink)

This project investigates naturalized metaphysics as a recent trend in analytic metaphysics originating in the naturalist attitude of James Ladyman and Don Ross in their seminal work Everything must Go: Metaphysics Naturalized (2007). The primary focus, however, will be the more recent article “Neo-Positivist Metaphysics” (2012) by Alyssa Ney that originates in this tradition. The project will conclude that naturalized metaphysics is an unsuccessful attempt at an answer to the question ’how is metaphysics possible’. More precisely, the project will establish (...) that any answer to this question must instruct how to succeed at attempts at assertions about the Kantian thing in itself. This requirement is the result of an argument that no other conception of ’reality’ is robust enough to accommodate an ambitious metaphysics. Subsequently, it will be argued that naturalized metaphysics is conceived by its proponents as an attempt at such an answer, but that naturalized metaphysics does not provide the required instruction. This problem occurs because of Carnap’s challenge to metaphysics. Carnap observes that no assertion can be made outside a linguistic framework which has the consequence that metaphysical assertions must be about the conceptual conventions of the linguistic framework rather than the thing in itself. It is the view of Ney and the other proponents of naturalized metaphysics that metaphysics is possible as a naturalized metaphysics; a metaphysics that appropriately defers or yields to the findings of science. The project argues that this requirement does nothing to ensure that Carnap’s challenge is avoided. The challenge is equally significant to naturalized and non-naturalized metaphysics, so long as both require that successful attempts at metaphysics must be assertions about the thing in itself. -/- The project concludes that until or unless Carnap’s challenge is refuted, naturalized metaphysics remain impossible, just like the metaphysics it is supposed to replace. (shrink)

Although we often see references to Carnap’s inductive logic even in modern literatures, seemingly its confusing style has long obstructed its correct understanding. So instead of Carnap, in this paper, I devote myself to its necessary and sufficient commentary. In the beginning part (Sections 2-5), I explain why Carnap began the study of inductive logic and how he related it with our thought on probability (Sections 2-4). Therein, I trace Carnap’s thought back to Wittgenstein’s Tractatus as well (Section 5). In (...) the succeeding sections, I attempt the simplest exhibition of Carnap’s earlier system, where his original thought was thoroughly provided. For this purpose, minor concepts to which researchers have not paid attention are highlighted, for example, m-function (Section 8), in-correlation (Section 10), C-correlate (Section 10), statistical distribution (Section 12), and fitting sequence (Section 17). The climax of this paper is the proof of theorem (56). Through this theorem, we will be able to overview Carnap’s whole system. (shrink)

Recent Carnap scholarship suggests that the received view of the Carnap-Quine analyticity debate is importantly mistaken. It has been suggested that Carnap’s analyticity distinction is immune from Quine’s criticisms. This is either because Quine did not understand Carnap’s use of analytic-ity, or because Quine did not appreciate that, rather than dispelling dog-mas, he was merely offering an alternate framework for philosophy. It has also been suggested that ultimately nothing of substance turns on this dis-pute. I am sympathetic to these (...) reassessments and their rejection of the re-ceived view, but argue that they fail to pay proper attention to Carnap’s metaphysical deflationism. For it is there that Quine’s arguments ultimately make contact with Carnap, undermining his metaphysical deflationism. Moreover, the viability of deflationism is directly related to the viability of Carnap’s view of philosophy as methodologically distinct from science. Hence, Quine’s criticisms make contact with the deepest aspects of Carnap’s views. (shrink)

W. V. Quine’s criterion of ontological commitment is commonly presented as the slogan: “to be is to be the value of a variable”. More specifically, to be is to be in the domain of values of a bound variable attached to a existential quantifier in the body of a theory. If a sentence of our best available theory quantifies over bachelors, so we conclude that, according to it, there are bachelors. Simplicity and the use of logical apparatus for determining this (...) criterion are responsible for many philosophers to adhere to this standpoint within analytical metaphysics. I will argue that despite this strong influence of the Quinean criterion of ontological commitment in many debates, we find at least three interlinked problems in its original formulation: (1) The criterion depends of a clear definition of theory for the determination of the quantifications counting as entailers of ontological commitments. However, Quine does not present such clear concept of what would be a theory and of how to formalize it. Quine develops this notion under just the metaphor of the knowledge fabric, in which we have a group of sentences, which does not suffice for the required account of ontological commitment. (2) There are distinct possibilities of quantifying over given sentences, which leaves room for different ontological commitments associated with the same statement. In that sense, someone could argue that the Quinean solution would be to endorse just the first order predicate logic. Nonetheless, the Quinean should explain why we ought to be restricted to this logic. (3) The previous problems lead to a possible explosion of the Quinean criterion of ontological commitment, making it trivial, because it permits the quantification over any supposed entities and, hence, that anything can exist. Thus, I will discuss Quine’s criterion of ontological commitment in the light of the abovementioned problems, showing that, unless the Quinean presents a more specific definition of theory beyond just a group of sentences, he leads to an explosion of commitments with different entities. I will conclude that, if you understand ‘theory’ as Alonzo Church’s concept of ‘formalized language’, this knot can be undone. However, Church’s concept is much more akin to Carnap’s linguistic framework than to a notion of knowledge fabric “without borders” as the one proposed by Quine. (shrink)

Against Thomas Mormann's argument that differential topology does not support Carnap's conventionalism in geometry we show their compatibility. However, Mormann's emphasis on the entanglement that characterizes topology and its associated metrics is not misplaced. It poses questions about limits of empirical inquiry. For Carnap, to pose a question is to give a statement with the task of deciding its truth. Mormann's point forces us to introduce more clarity to what it means to specify the task that decides between competing (...) hypotheses and in what way such a task may be both in practice and/or in principle impossible to carry out. (shrink)

This paper is a short introduction to Carnap’s writings on semantics with an emphasis on the transition from the syntactic period to the semantic one. I claim that one of Carnap’s main aims was to investigate the possibility of the symmetry between the syntactic and the semantic methods of approaching philosophical problems, both in logic and in the philosophy of science. This ideal of methodological symmetry could be described as an attempt to obtain categorical logical systems, i.e., systems that allow (...) only the intended semantical interpretation. (shrink)

Logical pluralism is the claim that there is more than one adequate logic. Many authors consider Carnap as one of the forerunners of logical pluralism. More than that, they claim that Carnap’s Principle of Tolerance consists in one of the first explicit formulations a logical pluralism. Nonetheless, there is little detailed investigation to evaluate if the Principle of Tolerance necessarily implies a logical pluralism, and if so, of which kind. The aim of this paper is to analyze the Principle of (...) Tolerance, as well as its context, and to investigate the relation between such principle and logical pluralism. (shrink)

Carnap and Twentieth-Century Thought: Explication as En lighten ment is the first book in the English language that seeks to place Carnap's philosophy in a broad cultural, political and intellectual context. According to the author, Carnap synthesized many different cur rents of thought and thereby arrived at a novel philosophical perspective that remains strik ing ly relevant today. Whether the reader agrees with Carus's bold theses on Carnap's place in the landscape of twentieth-century philosophy, and his even bolder (...) claims concerning the role that philosophy in Carnap's style should play in the thought of our century, does not matter so much as the excellent opportunity Carus's book offers to thoroughly rethink one's ideas about Carnap's philosophy. One reason why Carnap and Twentieth-Century Thought might change one's ideas is that Carus has unearthed much hitherto unknown material from the archives that sheds new light on Carnap's early life and thought. Indeed, the many archival findings presented in CTT for the first time suffice to make the book re warding reading for philosophers and historians of philosophy alike. CTT exhibits a high standard of historical scholarship, and the book itself is a beautiful example of high-quality academic publishing. Up to now, Carnap has remained a controversial figure on the philo sophical scene. On the one hand, he has a solid reputation as a leading figure of logical positivism . According to conventional wisdom, this was a school of thought characterized by its formal and technical philosophy, as well as being rather dismissive of other ways of doing philosophy, dogmatically sticking to its own theses. As a typical example of this arrogant logical empiricist attitude, one usually refers to Carnap's notorious Overcoming Metaphysics by Logical Analysis of Language , written when the Vienna Circle's Logical Empiricism had entered its most radical phase. Self-proclaimed postpositivist philosophers of science dismissed logical positivism, in particular Carnap's, as the dogmatic and orthodox “received view.” The tendency to portray logical empiricism as an obsolete doctrine centering around certain “dogmas” started with Quine's Two Dogmas of Empiricism and reached its somewhat ridiculous culmination in the early 1980s when allegedly “six or seven dogmas” were discovered . Thereby an allegedly un brid geable gap between classical “dogmatic” logical em pi ricism and its modern “enlightened” suc ces sors was construed. (shrink)

In his 1955 essay "Meaning and synonymy in natural languages", Rudolf Carnap presents a thought experiment wherein an investigator provides a hypothetical robot with a definition of a concept together with a description of an individual, and then asks the robot if the individual is in the extension of the concept. In this work, we show how to realize Carnap's Robot through knowledge probing of an large language model (LLM), and argue that this provides a useful cognitive tool for (...) conceptual engineers to compare the extension of a proposed concept definition to the extensional knowledge represented as facts in a given knowledge base, providing a possible solution to the implementation problem in conceptual engineering. (shrink)

Geometry was a main source of inspiration for Carnap’s conventionalism. Taking Poincaré as his witness Carnap asserted in his dissertation Der Raum (Carnap 1922) that the metrical structure of space is conventional while the underlying topological structure describes "objective" facts. With only minor modifications he stuck to this account throughout his life. The aim of this paper is to disprove Carnap's contention by invoking some classical theorems of differential topology. By this means his metrical conventionalism turns out to be (...) indefensible for mathematical reasons. This implies that the relation between to-pology and geometry cannot be conceptualized as analogous to the relation between the meaning of a proposition and its expression in some language as logical empiricists used to say. (shrink)

We characterize those identities and independencies which hold for all probability functions on a unary language satisfying the Principle of Atom Exchangeability. We then show that if this is strengthen to the requirement that Johnson's Sufficientness Principle holds, thus giving Carnap's Continuum of inductive methods for languages with at least two predicates, then new and somewhat inexplicable identities and independencies emerge, the latter even in the case of Carnap's Continuum for the language with just a single predicate.

Recent scholarship indicates that Quine’s “Truth by Convention” does not present the radical critiques of analytic truth found fifteen years later in “Two Dogmas of Empiricism.” This prompts a historical question: what caused Quine’s radicalization? I argue that two crucial components of Quine’s development can be traced to the academic year 1940–1941, when he, Russell, Carnap, Tarski, Hempel, and Goodman were all at Harvard together. First, during those meetings, Quine recognizes that Carnap has abandoned the extensional, syntactic approach to philosophical (...) analysis, an approach espoused in Carnap’s 1934 Logical Syntax of Language, and which Quine endorsed his entire career. Second, Tarski presents Quine with a philosophically well-motivated reason to think that an apparently analytic discipline, arithmetic, could be synthetic; this reflects one of the central assertions found in “Two Dogmas” but not in “Truth by Convention.” I use this account of Quine’s development to resolve a dispute between Creath and Mancosu concerning the timeline for Quine’s evolving critiques of analyticity. (shrink)

Due to their acceptance of the verifiability principle, the only way left for logical positivists to argue for the meaningfulness of religious language was to accept some sort of emotivistic conception of it or to reduce it to the description of religious attitude. The verifiability principle, however, suffers from some severe limitations that make it inadequate as a criterion for cognitive meaning. To resolve these problems, logical positivists gave up the requirement of conclusive verifiability and defended a sort of ‘liberalization’ (...) of the verifiability principle. Carnap’s confirmability criterion for cognitive meaning, which is a liberalized form of the verifiability principle, is compatible with an orthodox conception of religious language since, from a theistic perspective, the existence of God can be confirmed through our observational statements. (shrink)

Carnap’s Ideal of Explication and Naturalism is the second book on Rudolf Carnap’s philosophy edited by Pierre Wagner for Palgrave Macmillan’s series The History of Analytic Philosophy. The collection of essays is important for several reasons both for philosophers and historians of philosophy, but some parts of it will also be valuable to anyone interested in general scientific methodologies. I shall first survey the theme in order to locate the collection within the recent philosophical discussion then I will consider the (...) volume itself. (shrink)

Carnap’s result about classical proof-theories not ruling out non-normal valuations of propositional logic formulae has seen renewed philosophical interest in recent years. In this note I contribute some considerations which may be helpful in its philosophical assessment. I suggest a vantage point from which to see the way in which classical proof-theories do, at least to a considerable extent, encode the meanings of the connectives (not by determining a range of admissible valuations, but in their own way), and I demonstrate (...) a kind of converse to Carnap’s result. (shrink)

This paper takes two tasks. The one is elaborating on the relationship of inductive logic with decision theory to which later Carnap planned to apply his system (§§1-7); this is a surveying side of this article. The other is revealing the property of our prediction of the future, subjectivity (§§8-11); this is its philosophical aspect. They are both discussed under the name of belief in causation. Belief in causation is a kind of “degree of belief” born about the causal effect (...) of the action. As such, it admits of the analysis by inductive logic. (shrink)