Pierre Duhem rejected unambiguously the strong version of realism that he believed was held by Copernicus. In fact, although Copernicus believed that his theory was clearly superior to Ptolemy's, he seems to have recognized that his theory was at best only approximately true. Accordingly, he recognized that his arguments were not demonstrative in the traditional sense but probable and persuasive. Duhem regarded even the belief in probably true explanations as misguided. Nevertheless, Duhem recognized that, even if metaphysical intuition does not (...) enter into the content of physical theories, the rejection of hypotheses could be explained only by appeal to common sense. Hence, Duhem held a qualified instrumentalism according to which physical theories are not realist, but the terms of ordinary experience and empirical laws are realist. Accordingly, Duhem rejected the complete subordination of science to philosophy as well as the complete separation of science from philosophy. Duhem's history of cosmological doctrines reflects his belief in the origin of the subordination of science to philosophy and of the struggle to achieve the proper balance without being driven to the opposite extreme of their complete separation. (shrink)

This is a two tiered investigation. On the one hand, the author presents a systematic account of the philosophy of Hilary Putnam. Being the first comprehensive account to be published in the German-speaking world, the author traces the development of Putnam's realism and philosophy of language and their connections from the early 1950's to 2000. Contrary to the popular view of the discontinuity of Putnam's philosophy, he demonstrates that Putnam maintains certain semantic, pragmatic and epistemological foundations for the rational confirmability, (...) fallibility and self-corrigibility of theoretical knowledge in the empirical sciences as a constant around which many other philosophical assumptions are allowed to vary under critical examination. The resulting view of Putnam's philosophical "position" is decidedly "anti-metaphysical" (contrary to the common association of his philosophy of language with e.g. Kripke's understanding of realism), but not fully "deflationary" (contrary to the reclamation of his criticism of realist metaphysics as Quinean or Rortyan skepticism). On the other hand, the author generalizes, in the second and third parts of the book, Putnam's now famous theory of meaning and reference to develop a framework for the pragmatics of semantic continuity and discontinuity, as well as conceptual change within general terms in empirical settings, like natural kind terms, theoretical terms in natural sciences and commonsense classifications. The third part presents, develops and defends the basic normative premisses as a pragmatic alternative to both, metaphysical (Kripke, Devitt) and sceptical approaches (Quine, Kuhn). The main result here is that many (if not all) preconditions for the semantic bahvior of 'rigid' general terms are not, as usually assumed, ontological in nature, but can be usefully framed as part of the pragmatics of general terms in epistemic practices counting with rational revisability. (shrink)

One of the complications of a clear evaluation of different positions called “realism” in metaphysics and ontology is discrepancy in terminology and variance of basic intuitions inherent this notion. I recommend a taxonomy that distinguishes three kinds of variance: variance in the sets of conditions for a philosophical position to be acknowledged as actual realism, variance in strength and variance in conceptual frameworks. Within this last case, I propose to differentiate realism in epistemology, in ontology, and in metaphysics, intersecting these (...) three variants with the local/global realism dichotomy. The taxonomy here provided aims at being meta-philosophical; expressive enough for a fine-grained articulation of different philosophical positions in the recent debate, including the question of metaphysical grounding; and impartial, with no need to be connected to the defense of one form or another of the philosophical positions called “realism.”. (shrink)

Quantum mechanics studies physical phenomena on a microscopic scale. These phenomena are far beyond the reach of our observation, and the connection between QM's mathematical formalism and the experimental results is very indirect. Furthermore, quantum indeterminism defies common sense. Microphysical experiments have shown that, according to the empirical context, electrons and quanta of light behave as waves and other times as particles, even though it is impossible to design an experiment that manifests both behaviors at the same time. Unlike Newtonian (...) physics, the properties of quantum systems are not all well-defined simultaneously. Moreover, quantum systems are not characterized by their properties, but by a wave function. Although one of the principles of the theory is the uncertainty principle, the trajectory of the wave function is controlled by the deterministic Schrödinger equations. But what is the wave function? Like other theories of the physical sciences, quantum theory assigns states to systems. The wave function is a particular mathematical representation of the quantum state of a physical system, which contains information about the possible states of the system and the respective probabilities of each state. (shrink)