Alberto Cordero

Explanatory elucidation occurs when a theory has one or more of its assumptions explained by another independently successful theory. Because explanatory elucidation springs from independently supported theories, it improves the credibility of the assumptions it casts light on, hence its relevance for realists. But cases can be pointed to where explanatory elucidation has badly failed to identify truthful components. One way to address this challenge is by trying to find additional epistemic support for seemingly meritorious theory-parts. Resource in this regard, I suggest, include some specific lines of probing that regularly turn up against theories in mature scientific disciplines. Together with explanatory elucidation, those lines single out, in diachronic fashion, theory components worthy of realist commitment, or so I argue.

Modern cosmology, though a confluence of relativity theory and elementary particle physics, and with the help of very sophisticated mathematical models, tries to encompass the Universe as a whole, and to propose theories regarding its origin and evolution. But this cannot work without the evolution of several philosophical issues, concerning the epistemological status of this enterprise, its implicit or explicit extra-scientific presuppositions, as well as the real sense and interpretation of the theories and principles involved. This book provides a survey of these different aspects, for it gives some essential elements of the scientific background necessary for understanding the main issues of modern cosmology, and at the same time offer a discussion of the problems arising in it; problems which are never purely scientific, nor purely philosophical. Science and philosophy are therefore again deeply interrelated, at the moment where man tries to understand the Universe and his place in it. And this not only because the legitimacy of calling cosmology a science implies the acceptance of intellectual approaches which overstep the usual criteria of physical science and have a deep philosophical connotation, but also because the evolutionary way of thinking, strongly backed by cosmology, reinforces the role of this approach in the philosophy of science and in philosophy in general.

Summary: Responding to Laudan’s skeptical reading of history an influential group of realists claim that the seriously wrong claims past successful theories licensed were not really implicated in the predictions that once singled them out as successful. For example, in the case of Fresnel’s theory of light, it is said that although he appealed to the ether he didn’t actually need to in order to derive his famous experimental predictions—in them, we are assured, the ether concept was “idle,” “inessential,” “peripheral” or worse. This view, developed by J. Worrall and P. Kitcher in the 1980s and subsequently supplemented by J. Leplin and by S. Psillos has received critical attention in the literature over the last decade, but more needs to be said on the subject—or so I suggest in this paper. I bring forward four converging argumentative lines to show how and why, from the days of Fresnel to at least the decade after the Michelson-Morley experiments, the ether functioned and was understood as an “essential” posit in physics. My first line draws Fresnel’s actual deployment of the ether concept and the way he and his circle understood the achievements of his theory. The second line draws is from epistemological assessments of surprising implication in theories and its impact on leading theorists in the last two-thirds of the century. The third line draws from discussions of the optical ether in end-of-century reports circa 1900. The fourth focuses on entrenched metaphysical assumptions that persisted in the practice of physics until the advent of special relativity. Pulling these four lines together shows, I think, why attempts at synchronic identification of sound theory-parts are bound to fail, and also how realists might try to meet the challenge this creates.

Although exceptionally successful in the laboratory, the standard version of quantum theory is marred as a realist-objectivist proposition because of its internal conceptual difficulties and its tension with important parts of physics—most conspicuously, relativity theory. So, to meet these challenges, in recent years at least three distinct major objectivist programs have been advanced to further quantum theory into a proper general account of material systems. Unfortunately, the resulting proposals turn out to be, for all practical purposes, empirically equivalent both among themselves and against the standard version. This paper analyzes the basic issues involved in the case. It is argued that (a) the global anti-realist conclusion derived from it are fallacious, and (b) the encountered underdetermination shows how contingent upon the state of empirical knowledge talk about the “limits of science” actually is.

This paper examines some physical sources of the concept of objective state reduction in quantum mechanics. Using case studies from nuclear physics and quantum chemistry, the question of whether one can induce a collapse theory from the practices of scientists working on specific problems is considered. A specific proposal is explored, with emphasis on such features as coherence, testability, unifying power and fertility. It is shown that, contrary to recent suggestions by David Albert, collapse theories are philosophically promising developments worthy of further study. Some philosophical implications of the development of collapse theories are discussed.

Using the optical ether as a case study, this article advances four lines of consideration to show why synchronic versions of the divide et impera strategy of scientific realism are unlikely to work. The considerations draw from the nineteenth-century theories of light, the rise of surprising implication as an epistemic value from the time of Fresnel on, assessments of the ether in end-of-century reports around 1900, and the roots of ether theorizing in now superseded metaphysical assumptions. The typicality of the case and its impact on diachronic versions of the strategy are briefly discussed.

Breaking away from logical-empiricism, in the early 1950s Stephen Toulmin presented empirical theories as maps, thereby opening a fertile line of reflection about background interests and their impact on abstraction in scientific theorizing. A few years later, pointing to the “qualitative infinity of nature,” David Bohm denounced what he regarded as counterproductive constraints on the scientific imagination. In realist circles, these two strands of suggestions would be variously supplemented over the following decades with further recognitions of the epistemic merits of partial approximate descriptions and the role of background knowledge and interests in scientific theorizing. Rompiendo con el empirismo lógico, en la década de 1950 Stephen Toulmin presenta como mapas las teorías empíricas, abriendo así una línea fértil de reflexión sobre los intereses que motivan cada teoría y el impacto de dichos intereses en la abstracción en la teorización teórico/científica. Unos años más tarde David Bohm, señalando el “infinito cualitativo de la naturaleza”, denunció lo que él consideraba restricciones contraproducentes en la imaginación científica. En los círculos realistas, estas dos visiones serán complementadas de diversas maneras durante las siguientes décadas con reconocimientos de los méritos epistémicos de las descripciones aproximadas parciales y el papel de los intereses y conocimientos previos en la teorización científica.