Alberto Cordero

Recent attempts to turn Standard Quantum Theory into a coherent representational system have improved markedly over previous offerings. Important questions about the nature of material systems remain open, however, as current theorizing effectively resolves into a multiplicity of incompatible statements about the nature of physical systems. Specifically, the most cogent proposals to date land in effective empirical equivalence, reviving old anti-realist fears about quantum physics. In this paper such fears are discussed and found unsound. It is argued that nothing of global skeptical or agnostic significance follows from the kind of underdetermination presently encountered in fundamental quantum theory. The case is instructive, however, for what it shows about the characteristics and prospects of scientific realism as a perspective in contemporary philosophy of science.

Las interpretaciónes de la física cuántica de Everett-DeWitt hablan de una multiplicidad de mundos físicamente coexistenrtes. Éstas imaginativas reacciones a los problemas conceptuales de la mecánica cuántica estándar forman una família de propuestas de “universos múltiples” que, sin pleno éxito, han sido tachadas de incoherentes.Everett-DeWitt interpretations of quantum physics speak of a multiplicity of physically coexisting worlds. These imaginative reactions to the conceptual problems of standard quantum mechanics form a family of physicalist “many-worlds” proposals that have been variously dismissed as “incoherent”, so far without full success. A renewed charge by Hilary Putnam now seems to pose deeper trouble for PMW. In a recent paper, he seizes on “Schrödinger’s cat” situations to expose how PMW relativization of actuality and basic combinatorics jointly ruin probabilistic talk. Putnam focuses on confirmation and luck. His case against PMW is thought-provoking but also questionable, or so I suggest in this paper. First I argue that, as presented, Putnam’s charge doesn’t go through. I then consider his argument proper. According to Putnam, experimental DeWittians must count themselves as “lucky” in a seriously incoherent sense. I consider his take on “luck” and deny that defenders of PMW need to so regard themselves. Although extravagant, their position cannot be fruitfully dismissed as incoherent on metascientific grounds. Indeed it attests to the way science rationally helps the imagination to grow.

According to an old way of thinking, any leve! of problematicity with respect to truth or theory dependence suffices to spoil the objectivity of a proposal. No credible discourse complies with such restrictions. Far from compromising the existence of knowledge, correct and incorrect, rational and nonrational ideas, however. the said old way of thinking is simply incapable of representing the cognitive achievements that we actually have. This paper discusses a contemporary way of approaching the difference between ideas of high and low descriptive quality in terms of epistemological criteria that prevail in the most rigorous and reliable scientific practices.

Some thinkers distrust Darwinist explorations of complex human behaviors, particularly investigations into possible differences in valued skills between genders, races or classes. Such projects, it is claimed, tend to have adverse effects on people who are already disadvantaged. A recent argument by Philip Kitcher both clarifies and generalizes this charge to cover a whole genre of scientific projects. In this paper I try to spell out and analyze Kitcher's argument. The argument fails, I suggest, because some of its key premises fail to convince. My analysis focuses on relevant facts about the role of inquiry in fallibilist contexts, the texture of belief in contemporary natural science, and the moral dimension of scientific research.

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.