Carnap: Epistemology

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)

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)

A brief introduction to the life and key work of Rudolf Carnap with special attention to his work on inductive logic.

The rise of experimental philosophy has placed metaphilosophical questions, particularly those concerning concepts, at the center of philosophical attention. X-phi offers empirically rigorous methods for identifying conceptual content, but what exactly it contributes towards evaluating conceptual content remains unclear. We show how x-phi complements Rudolf Carnap’s underappreciated methodology for concept determination, explication. This clarifies and extends x-phi’s positive philosophical import, and also exhibits explication’s broad appeal. But there is a potential problem: Carnap’s account of explication was limited to empirical and (...) logical concepts, but many concepts of interest to philosophers are essentially normative. With formal epistemology as a case study, we show how x-phi assisted explication can apply to normative domains. (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)

An overview of Quine's understanding of the analytic/synthetic distinction, especially as it is conveyed in his paper, "The Two Dogmas of Empiricism.".

I argue that Quine’s rejection of Carnap’s “radical” (FLPV; TDE 39) and “phenomenalistic” (FSS 15-16) reductionism—as it is manifest in the Aufbau—may be understood in terms of a broader historical context. In particular, it may be understood as a rejection of a contemporary variant of the second horn of Meno’s Paradox. As a result, Quine’s motivation to adopt naturalism may be understood independently of his pragmatic concerns. According to Quine, it was simply unreasonable (i.e. paradoxical) to adopt a Carnapian phenomenalistic/mentalistic (...) (non-naturalistic) approach to epistemology. Armed with what could only be his invigorated faith in the naturalistic method, he was then, as I see it, equipped to break what we may characterize as the physicalistic version of the naturalistic circle. This is a repudiation that, I show, entails his rejection of “attenuated” (FLPV; TDE 41) reductionism and concomitantly, his rejection of “analyticity,” if not “certainty” altogether. As a result, Quine could simultaneously dismiss what we may characterize as the Humean version of the naturalistic circle. Meanwhile, the practicality of an admittedly fallible science could be unashamedly embraced, although not just for the sake of its practicality—as Quine himself seems to misleadingly indicate throughout his work—but instead, as just noted, to avoid the seemingly Platonic paradox of Aufbauian reductionism. (shrink)

The verification theory of meaning aims to characterise what it is for a sentence to be meaningful and also what kind of abstract object the meaning of a sentence is. A brief outline is given by Rudolph Carnap, one of the theory's most prominent defenders: If we knew what it would be for a given sentence to be found true then we would know what its meaning is. [...] thus the meaning of a sentence is in a certain sense identical (...) with the way we determine its truth or falsehood; and a sentence has meaning only if such a determination is possible. [4: 420] In short, the verification theory of meaning claims that the meaning of a sentence is the method of its verification. (shrink)

Einführung in die Philosophie Rudolf Carnaps.

Hume and Quine argue that human beings do not have access to general knowledge, that is, to general truths . The arguments of these two philosophers are premised on what Jaakko Hintikka has called the atomistic postulate. In the present work, it is shown that Hume and Quine in fact sanction an extreme version of this postulate, according to which even items of particular knowledge are not directly accessible in so far as they are relational. For according to their fully (...) realized systems, human beings do not initially perceive any relations, or similar epistemological elements that can associate or combine terms on which a relational or general knowledge claim may be based. Nor, likewise, do human beings perceive the relations or the associations themselves as separate entities. ;In Chapters 1 and 2, respectively, it is shown precisely why Hume and Quine deny that human beings initially perceive either such associative elements or associations in general. Concomitantly, it is made clear why Hume's and Quine's respective epistemologies preclude human beings from initially apprehending not only general knowledge, but particular relational knowledge as well. But this is not to say that Hume and Quine do not think we can eventually acquire such associative elements and correspondingly, knowledge. Rather, Hume and Quine do provide an account of knowledge, but one that holds all relational and connective elements to be constructed by the human mind. In Hume's case, they are constructed by the imagination. In Quine's case, we are never told quite how this construction occurs, although the evidence suggests that Quine implicitly relies on a faculty similar to Hume's imagination. ;In the final chapter of this thesis, it is argued that both Hume and Quine must be read as philosophers who justify knowledge by reducing its possibility to a psychological faculty of construction, as well as to a few concepts of intuitively grasped relations. By way of conclusion, it is shown that this makes Quine's naturalism the psychological heir to Carnap's Aufbau. (shrink)

The concept of similarity has had a rather mixed reputation in philosophy and the sciences. On the one hand, philosophers such as Goodman and Quine emphasized the „logically repugnant“ and „insidious“ character of the concept of similarity that allegedly renders it inaccessible for a proper logical analysis. On the other hand, a philosopher such as Carnap assigned a central role to similarity in his constitutional theory. Moreover, the importance and perhaps even indispensibility of the concept of similarity for many empirical (...) sciences can hardly be denied. The aim of this paper is to show that Quine’s and Goodman’s harsh verdicts about this notion are mistaken. The concept of similarity is susceptible to a precise logico-mathematical analysis through which its place in the conceptual landscape of modern mathematical theories such as order theory, topology, and graph theory becomes visible. Thereby it can be shown that a quasi-analysis of a similarity structure S can be conceived of as a sheaf (etale space) over S. (shrink)