Roberto Angeloni

What I want to point out is the “meaning change” that Friedman ascribes to terms and principles, which he calls a priori, in the transition from the old framework to the new: 'This captures the sense, in particular, in which there has indeed been a ”meaning change” in the transition from the old framework to the new: even if the same terms and principles reappear in the new framework they do not have the same meaning they had in the old' (Friedman 2001, p. 99, ft. 37). Following Friedman, we should admit that the same words possess different meanings in different frameworks. In fact, terms and principles that are empirical in an old framework may shift to constitutive status in the new framework, and vice- versa. If Friedman’s account seemed to entrust the prospective rationality of science to constitutive a priori principle, the notion of meaning change suggests instead that Friedman’s argument upholds the Kuhnian account of incommensurability, while we were expecting he aimed to mitigate it. As he clearly states in the passage to follow: 'The later framework is not translatable into the earlier framework, of course, simply because the concepts used in formulating the later framework have not yet come into existence' (Friedman 2001, pp. 98-99). Friedman’s account purports to emphasize that a transition from empirical laws to principles, and vice-versa, should imply a conceptual shift. But is “meaning change” the appropriate expression that may describe such a conceptual shift? What does the word “concept” mean for Friedman? How are concepts related to the meaning of terms? What does the “meaning” mean in Friedman’s view? What is the relation between terms and theories? Does theory change entail a meaning change of scientific terms, that is, do terms determine theory change (i.e. difference in theories is ipso facto difference in terms)? Recently, some specialists (Tsou 2010, for instance) have stressed Friedman’s notion of constitutive a priori principle in light of Putnam’s positive account of apriority. Friedman's and Putnam’s notions of relativized a priori are presented as similar insofar as they both affirm the existence of principles in science, which are revisable and relativized to a particular body of knowledge. However, the similarities do not take into account that Friedman ascribed a meaning change to coordinating principles that are constitutive of the new framework. Could Putnam subscribe such a meaning change? This paper aims to analyse Friedman’s notion of constitutive a priori principle in relation to the problem of meaning change by taking into account Putnam’s theory of meaning and his notion of framework principle.

In the present paper I aim to discuss the philosophical foundations of the early correspondence principle, by comparing the conceptual structure underlying the first correspondence principle with the procedure of analogy that Immanuel Kant introduced in the Critique of Judgment from 1790. On such a comparison, I will seek to demonstrate the consistency of the conceptual ratio according to which the correspondence principle is to the classical "concepts" of space and time, as these a priori forms of intuition, in Kant, are related to the separate faculty of pure intuition. As a result, it will turn out that the conceptual structure of the correspondence principle suits to the Kantian doctrine of a separate faculty of pure intuition, which is divided from the faculty of understanding. The aim is to shed new light on the line of reasoning underlying Niels Bohr's analogical thinking in quantum physics.

I propose a rational reconstruction of the early quantum theory (1900–1913) in terms of the ideas presented by Ernst Cassirer. Specifically, I propose to reconsider the early quantum theory through the lens of the method of conceptual functionalization that Ernst Cassirer laid down in his Substance and Function (S&F, 1910) and he later refined in Determinism and Indeterminism in Modern Physics (D&I, 1937). Following Cassirer’s functional interpretation of natural sciences, it is my primary concern to reconsider the conceptual evolution of Planck’s quantum of action from 1900 to 1913. In this regard, I shall emphasize the importance of the quantum of action (Planck’s constant) in the architectonic structure of the early quantum theory, in the role of an element of fundamental continuity between the first quantum theory and the formulation by Niels Bohr of the first atomic theory.

It is my aim to compare the conceptual and historical paths that led Bohr and Schrödinger to develop their positions with regard to the phenomenon of entanglement. For this purpose, the concept of holism and non-separability in relation to the views of Bohr and Schrödinger will be crucial for reconstructing their standpoints. The idea will be upheld that the concept of non-separability underlies the phenomenon of entanglement. Furthermore, I shall place emphasis on the divergences between Bohr and Schrödinger in spite of their shared holistic world view.

It is this paper’s aim to shed some light on the debate about the cultural debt of Niels Bohr towards his mentor and teacher of philosophy, Harald Høffding. The debate began at the end of seventies between two Danish scholars, Jan Faye and David Favrholdt, and in a broader sense it stands for way to show how philosophical influences may shape the scientist’s outlook on the world and consequently the approach to his field of studies. In my view, Edgar Rubin, the famous psychologist and Bohr’s friend, is the key person to reconsider the Bohr-Høffding’s relationship. I shall adopt Gerald Holton’s thematic analysis for enucleating the possible thematic concept that supports the claim of a common line of thought emerging from Høffding, Rubin and Bohr’s conceptions with respect to their own field of study. Such a line of thought, i.e. the concept of unity, moulded Bohr’s view on the world and exerted its heuristic power in the formulation of the first atomic theory.

The monograph offers a thematic account of Niels Bohr’s scientific and philosophical thought. Starting from epistemological considerations relating to Lakatos’ Methodology of Scientific Research Programmes, it was the author’s aim to go back to the origin of the heuristic underlying Bohr’s theories on quantum physics. Then he came to integrate Lakatos’ view on methodology with Holton’s idea of thematic origin of scientific thought. Following these premises, it turned out, perhaps surprisingly, that Bohr’s basic methodological principle was the condition of continuity rather than discontinuity. Moreover, almost as a consequence of the thematic analysis, it became a priority of this volume to establish connections between so-called external factors and the ‘‘rational’’ development of the program.