The propositions of a scientific theory are connected with empirical states of affairs. Determining how theoretical propositions are connected with empirical facts, what Carnap called the “empirical significance” of a theory, is a complex affair. Carnap’s account of the relationship between theoretical frameworks and methods of observation has come in for plentiful criticism, alleging that Carnap’s theory of science does not allow for a sophisticated entwinement of theory and observation, instead favoring heavy formalism and a brittle reductionism. I present evidence that Carnap’s account of the distinction between theoretical and observation languages is more flexible than it is usually depicted to be and is motivated by his philosophy of science. In particular, in his mature work Carnap argues that the "specific calculus" of a scientific theory, including mathematical structure and physical laws, are included in the axiomatic foundations and linguistic framework of that theory. Carnap’s account of language thus turns out to be deeply entangled with his philosophy of science, and one cannot be understood independently of the other.

It has become a commonplace that Carnap is the lead empiricist in Quines Two Dogmas of Empiricism. Recent work by Richard Creath, Robert Sinclair, and others stirs up this comfortable narrative, pointing to broader areas of agreement between Quine and Carnap, including Quines positive assessment of the Logische Syntax in his Lectures on Carnap, and the influence of pragmatism on both.  Following a hint from a colleague, I investigate whether at least some strains of empiricism that Quine rejects in Two Dogmas belong to Quines mentor, C. I. Lewis, instead. The paper assesses the philosophical and historical consequences of reading Two Dogmas in this way.

Recent readings of Kant’s Metaphysical Foundations of Natural Science begin with the claim that Kant presents a theory of matter, and of the interactions between material substances, in that work. Emphasizing this point raises a question that comes up in interpretations of the Metaphysical Foundations more generally: What is more fundamental to Kant’s account of matter? A description of how law-governed interactions are explained as arising from the essential properties and powers of objects (the Necessitation Account)? Or an account of how we come to know universal laws of nature via formal inferences regarding the a priori foundations of particular empirical laws (the Derivation Account)? Or a Best System Interpretation (BSI), on which “the particular laws of nature are those empirical generalizations that would figure in the best systematization of the empirical data at the ideal end of inquiry” (Breitenbach 2018, 111)?

Two questions should be considered when assessing the Kantian dimensions of Kuhn’s thought. Was Kuhn a Kantian? Did Kuhn have an influence on later Kantians and neo-Kantians? Kuhn mentioned Kant as an inspiration, and his focus on explanatory frameworks and the conditions of knowledge appear Kantian. But Kuhn’s emphasis on learning; on activities of symbolization; on paradigms as practical, not just theoretical; and on the social and community aspects of scientific research as constitutive of scientific reasoning are outside the Kantian perspective. Kuhn’s admiration for Kant is tempered by his desire to understand the processes of learning, initiation into a scientific community, experimentation using instruments, and persuasion, drawing on the work of Piaget, Koyré, Wittgenstein, and others. Both Kuhn and Kant were interested in the status of science, and the role of the scientist in its development and justification. But Kuhn presents science in a much more messy, historically contingent, and socially charged way than Kant does. The paper’s conclusion evaluates Kuhn’s reception among researchers including Richardson and Friedman, assessing the prospects for future work.

Ernst Mach’s appeal to the ‘economy of science’ has sometimes been interpreted as an overarching principle of minimisation, promoting the increasing simplification of scientific knowledge via principles that increase calculating power without adding substantively to the knowledge embedded in empirical facts. There is a growing literature arguing for a more robust understanding of Mach’s ‘economy of science’. Machian ‘economy’ appeals to the continuity between scientific experiences and concepts, but also to the increasing complexity of scientific concepts, building on connections between what Mach called world-elements or sensation-elements. Mach’s account emphasises not only continuities between experiences that allow for simplification, but also areas of divergence that promote the branching of scientific concepts and methods. I emphasise the roles of abstraction, pragmatism, and history in Mach’s economy of science and argue that these elements allowed Mach to investigate the productive tension between creative and conservative moments in the history of science.