In the problem of the relationship between chemistry and physics, many authors take for granted the ontological reduction of the chemical world to the world of physics. The autonomy of chemistry is usually defended on the basis of the failure of epistemological reduction: not all chemical concepts and laws can be derived from the theoretical framework of physics. The main aim of this paper is to argue that this line of argumentation is not strong enough for eliminate the idea of (...) a hierarchical dependence of chemistry with respect to physics. The rejection of the secondary position of chemistry and the defense of the legitimacy of the philosophy of chemistry require a radically different philosophical perspective that denies not only epistemological reduction but also ontological reduction. Only on the basis of a philosophically grounded ontological pluralism it is possible to accept the ontological autonomy of the chemical world and, with this, to reverse the traditional idea of the ‘superiority’ of physics in the context of natural sciences. (shrink)

In this paper we argue that the formalisms for decoherence originally devised to deal just with closed or open systems can be subsumed under a general conceptual framework, in such a way that they cooperate in the understanding of the same physical phenomenon. This new perspective dissolves certain conceptual difficulties of the einselection program but, at the same time, shows that the openness of the quantum system is not the essential ingredient for decoherence. †To contact the authors, please write to: (...) Mario Castagnino, CONICET-IAFE, Universidad Nacional de Buenos Aires, Casilla de Correos 67, Sucursal 28, 1428 Buenos Aires, Argentina; Roberto Laura, IFIR-Universidad Nacional de Rosario, Av. Pellegrini 250, 2000 Rosario, Argentina; Olimpia Lombardi, CONICET-Universidad Nacional de Buenos Aires, C. Larralde 3440, 6°D, 1430, Buenos Aires; e-mail: [email protected]. (shrink)

The aim of this paper is to analyze time-asymmetric quantum mechanics with respect of its validity as a non time-reversal invariant, time-asymmetric theory as well as of its ability to determine an arrow of time.

The modal-Hamiltonian interpretation belongs to the modal family of interpretations of quantum mechanics. By endowing the Hamiltonian with the role of selecting the subset of the definite-valued observables of the system, it accounts for ideal and non-ideal measurements, and also supplies a criterion to distinguish between reliable and non-reliable measurements in the non-ideal case. It can be reformulated in an explicitly invariant form, in terms of the Casimir operators of the Galilean group, and the compatibility of the MHI with the (...) theory of decoherence has been proved. Nevertheless, perhaps its main advantage in the eyes of a scientist is given by its several applications to well-known physical situations, leading to results compatible with experimental evidence. The purpose of this paper is to add a new application to the list: the case of optical isomerism, which is a central issue for the philosophy of physics and of chemistry since it points to the core of the problem of the relationship between physics and chemistry. Here it will be shown that the MHI supplies a direct and physically natural solution to the problem, a solution that does not require putting classical assumptions in “by hand.”. (shrink)

Philosophers of science have often favoured reductive approaches to how-possibly explanation. This article identifies three alternative conceptions making how-possibly explanation an interesting phenomenon in its own right. The first variety approaches “how possibly X?” by showing that X is not epistemically impossible. This can sometimes be achieved by removing misunderstandings concerning the implications of one’s current belief system but involves characteristically a modification of this belief system so that acceptance of X does not result in contradiction. The second variety offers (...) a potential how-explanation of X. It is usually followed by a range of further potential how-explanations of the same phenomenon. In recent literature the factual claims implied by the second variety have been downplayed whereas the heuristic role of mapping the space of conceptual possibilities has been emphasized. I will focus especially on this truth-bracketing sense of potentiality when looking closer at the second variety in the paper. The third variety has attracted less interest. It presents a partial how-explanation of X. Typically it aims to establish the existence of a mechanism by which X could be and was generated. The third conception stands out as the natural alternative for the advocate of ontic how-possibly explanations. This article transfers Salmon’s view that explanation-concepts can be broadly divided into epistemic, modal, and ontic to the context of how-possibly explanations. Moreover, it is argued that each of the three above-mentioned varieties of how-possibly explanation occurs in science. To recognize this may be especially relevant for philosophers. We are often misled by the promises of various why-explanation accounts, and seem to have forgotten nearly everything about the diversity of how-possibly explanations. (shrink)

According to the environment-induced approach to decoherence, the split of the Universe into the degrees of freedom which are of direct interest to the observer and the remaining degrees of freedom is absolutely essential for decoherence. However, the EID approach offers no general criterion for deciding where to place the “cut” between system and environment: the environment may be “external” or “internal”. The main purpose of this paper is to argue that decoherence is a relative phenomenon, better understood from a (...) closed-system perspective according to which the split of a closed quantum system into an open subsystem and its environment is just a way of selecting a particular space of relevant observables of the whole closed system. In order to support this claim, we shall consider the results obtained in a natural generalization of the simple spin-bath model usually studied in the literature. Our main thesis will lead us to two corollaries. First, the problem of identifying the system that decoheres is actually a pseudo-problem, which vanishes as soon as one acknowledges the relative nature of decoherence. Second, the usually supposed link between decoherence and energy dissipation is misguided. As previously pointed out, energy dissipation and decoherence are different phenomena, and we shall argue for this difference on the basis of the relative nature of decoherence. (shrink)

This paper discusses three shortcomings of the current state of the debate regarding historical evidence against scientific realism. Attending to these issues will direct the debate away from over-generalising wholesale arguments.

Suppose that several observations “coincide,” meaning that they are similar in some interesting respect. Is this coinciding a mere coincidence, or does it derive from a common cause? Those who reason about this kind of question—whether they embrace the first answer or the second—often deploy a mode of inference that I call probabilistic modus tollens. In this chapter I criticize probabilistic modus tollens and consider likelihood and Bayesian frameworks for reasoning about coincidences. I also consider the perspective offered by model (...) selection theory (including the Akaike information criterion), and argue that model selection often provides important insights. (shrink)

Our account of the problem of the classical limit of quantum mechanics involves two elements. The first one is self-induced decoherence, conceived as a process that depends on the own dynamics of a closed quantum system governed by a Hamiltonian with continuous spectrum; the study of decoherence is addressed by means of a formalism used to give meaning to the van Hove states with diagonal singularities. The second element is macroscopicity represented by the limit $\hbar \rightarrow 0$ : when the (...) macroscopic limit is applied to the Wigner transformation of the diagonal state resulting from decoherence, the description of the quantum system becomes equivalent to the description of an ensemble of classical trajectories on phase space weighted by their corresponding probabilities. (shrink)

According to a wrong interpretation of the Bell theorem, it has been repeatedly claimed in recent times that we are forced by experiments to drop any possible form of realism in the foundations of quantum mechanics. In this paper I defend the simple thesis according to which the above claim cannot be consistently supported: the Bell theorem does not concern realism, and realism per se cannot be refuted in itself by any quantum experiment. As a consequence, realism in quantum mechanics (...) is not something that can be simply explained away once and for all on the basis of experiments, but rather something that must be conceptually characterized and discussed in terms of its foundational virtues and vices. To assess it, we cannot rely on experimentation but rather on philosophical discussion: realism is not a phlogiston-like notion, despite the efforts of the contemporary quantum orthodoxy to conceive it in Russellian terms as the relics of a bygone age. (shrink)

In this paper I distinguish between two kinds of meta-hypotheses, or hypotheses about science, at issue in the scientific realism debate. The first are descriptive empirical hypotheses regarding the nature of scientific inquiry. The second are epistemological theories about what individuals should / can justifiably believe about scientific theories. Favoring the realist Type-D meta-hypotheses, I argue that a particular set of realist and non-realist efforts in the debate over Type-E’s have been valuable in the quest to describe and understand the (...) nature of scientific inquiry. For the realism debate itself has inadvertently and indirectly laid the foundations for an important kind of Type-D meta-hypothesis, one regarding creativity in the history of science—which, in turn, is relevant to refining our descriptions of inference. After illustrating this result with regard to the historical argument against realism, I suggest that these empirically attained meta-hypotheses pertaining to scientific creativity can, in turn, be made methodologically prescriptive. (shrink)

Ilya Prigogine was not a systematic author: his ideas, covering a wide arch of areas, are dispersed in his many writings. In particular, his philosophical thought has to be reconstructed mainly on the basis of his works in collaboration with Isabelle Stengers: La Nouvelle Alliance ( 1979 ), Order out of Chaos ( 1984 ), and Entre le Temps et l’Éternité ( 1988 ). In this paper I undertake that reconstruction in order to argue that Prigogine’s position, when read in (...) the light of Putnam’s internalist realism, can be characterized as an ontological pluralism. The main aim of this work is to show the striking parallelism between the philosophical views of Prigogine and Stengers and those of Hilary Putnam in Reason , Truth and History ( 1981 ). This task will lead me to critically review Prigogine’s general scientific program: the attempt to establish the foundations of objective irreversibility. (shrink)

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. (shrink)

The more common scheme to explain the classical limit of quantum mechanics includes decoherence, which removes from the state the interference terms classically inadmissible since embodying non-Booleanity. In this work we consider the classical limit from a logical viewpoint, as a quantum-to-Boolean transition. The aim is to open the door to a new study based on dynamical logics, that is, logics that change over time. In particular, we appeal to the notion of hybrid logics to describe semiclassical systems. Moreover, we (...) consider systems with many characteristic decoherence times, whose sublattices of properties become distributive at different times. (shrink)

Under the eternalist hypothesis that objects or events exist temporally, but independently of being present two different views of persistence are on the market: Persisting objects endure if they are multiply located in time, and persisting objects perdure if they are singly located by having numerically different temporal parts. In the framework of the special theory of relativity, the metaphysics of persistence is confronted with peculiar difficulties. Things persist by being “wholly present” at more than one time; but what are (...) times within a temporally non-separated spacetime? Things persist by having different temporal parts at different times; but what are the temporal parts of a four-dimensional object in Minkowski spacetime? Recently, several authors have argued that SR favours perdurantism over its endurantist rival. In this paper, I intend to show that the purported arguments are only those against endurantism. The first simply fails, but the second, more convincing one, is such that with a similar strategy we should argue against perdurantism as well: Enduring and perduring entities are hence both in conflict with SR which undermines the eternalist hypothesis. (shrink)

In this paper, I study the application of phylogenetic analysis in evolutionary archaeology. I show how transfer of this apparently general analytic tool is affected by salient differences in disciplinary context. One is that archaeologists, unlike many biologists, do not regard cladistics as a tool for classification, but are primarily interested in explanation. The other is that explanation is traditionally sought in terms of individual-level rather than population-level mechanisms. The latter disciplinary difference creates an ambiguity in the application and interpretation (...) of phylogenetic analyses. Moreover, I argue that, while archaeologists have claimed that “cladistics is useful for reconstructing artefact phylogenies”, these reconstructions only contribute minimally to the explanatory research agenda of evolutionary archaeology. (shrink)

My goal in this paper is to see the extent to which judgment aggregation methods subsume meta-analytic ones. To this end, I derive a generalized version of the classical Condorcet Jury Theorem, the aggregative implications of which have been widely exploited in the area of rational choice theory, but not yet in philosophy of science. I contend that the generalized CJT that I prove below is useful for modelling at least some meta-analytic procedures.

Most science requires applied mathematics. This truism underlies the Quine-Putnam indispensability argument: we cannot be mathematical nominalists without rejecting whole swaths of good science that are seamlessly linked with mathematics. One style of response accepts the challenge head-on and attempts to show how to do science without mathematics. There is some consensus that the response fails because the nominalistic apparatus deployed either is not extendible to all of mathematical physics or is merely a deft reconstrual equivalent to standard mathematics. A (...) second style of response denies that indispensability entails realism: when we mathematize a physical problem we treat its physical content as if it were the mathematical representation; provided the two are sufficiently similar, we can use the mathematics to draw conclusions about the physics; even if we cannot represent physical facts without mathematical tools, as-if-fictionalism is reasonable. In this paper I argue that uses of mathematics in science reach deeper than is appreciated by this second response and, indeed, in the more general literature. More specifically, our confidence that we can use the mathematics to draw conclusions about the physics itself depends on mathematics. If the mathematical premises we employ in concluding that a certain application is trustworthy are false, we may lack a justification for supposing that the application will reliably lead us from correct input to correct output. For example, solutions to many physical problems require the determination of a function satisfying a differential equation. Sometimes the existence of a solution for initial value problems can be established directly; where direct methods fail, the existence of a solution must be established indirectly, generally by constructing a sequence of functions that converges to a limit function that satisfies the initial value problem. Moreover, the solution often cannot be evaluated by analytic methods, and scientists must rely on finite element numerical methods to approximate the solution. Mathematical analysis of errors provides further useful information governing the choice of approximation method and of the step size and number of elements needed for the approximation to reach a desired precision. Mathematical physicists rely on the background mathematical theories presupposed in proving the existence of the solutions and approximating them. It is difficult to see how they could do this while adding the fictionalist disclaimer, “But, you know, I don’t believe any of the mathematics I’m using”. It is difficult to see how a fictionalist pursuing the second strategy can account for the soundness of mathematical reasoning in mathematical physics and elsewhere in the sciences. The paper will fill out this argument by appeal to examples and attempt to make clear how mathematics is indispensable to understanding – and thus underwriting our confidence in – applications that would otherwise be shaky approximations and idealizations and how this role is difficult to square with fictionalism. (shrink)

The function of metaphor in science has been labeled as decorative, persuasive, heuristic, instrumental, facilitating or obstructing. It has sometimes been regarded as inspiring, provoking, perverting or destroying rational thought. Metaphor’s positive role has been noted by philosophers, historians of chemistry, and science education researchers. It has been hailed as a descriptive and explanatory device that stimulates and shapes concept development. I discuss how metaphor functions in science generally, then refine this idea through an examination metaphor’s role in chemical thinking (...) in three contexts: the history and philosophy of chemistry, laboratory research practice, and chemical education. I aim to show how metaphor is already operative in the chemist’s use of the concept of chemical element and that this understanding characterizes chemical thinking in general. The chapter concludes with a discussion of a specifically chemical understanding of metaphor. (shrink)

In this paper, I critically assess the thesis that the discovery of mirror neuron systems provides empirical support for the simulation theory of social cognition. This thesis can be analyzed into two claims: that MNSs are involved in understanding others’ intentions or emotions; and that the way in which they do so supports a simulationist viewpoint. I will be giving qualified support to both claims. Starting with, I will present theoretical and empirical points in support of the view that MNSs (...) play a substantial role and are perhaps neces¬sary although not sufficient for understanding at least some intentions or emo¬tions. Turning to, I will argue that the work on MNSs best supports a fairly weak version of ST, according to which social cognition involves simulation simply because conceptual thought in gen¬eral has a simulationist component. In elucidating this idea, I appeal to Law¬rence Barsalou’s embodied theory of concepts. Crucially, the term “simula¬tion” here refers not to simulations of a target agent’s experience, nor even spe¬cifically to one’s own experience in a similar counterfactual situation, but to simulations of experience in general - activating sensory, motor, proprioceptive, affective, and introspective representations that match representations one would have when perceiving, carrying out actions, experiencing emotions, etc. I then sketch an expanded simulationist framework for understanding the contribution of MNSs to social cognition. The ap¬peal to empirical work on MNSs in support of ST is therefore a two-edged sword; making this appeal persuasive requires us to modify our understanding of simulation to make it line up with the empirical work. (shrink)

An argument to the effect that non-relativistic quantum particles can be understood as individual objects in spite of the empirical evidence seemingly lending support to the opposite conclusion. Ways to understand quantum indistinguishability and quantum statistics in terms of individuals are indicated.

In response to difficulties in understanding the notion of chemical substance at issue in Gibbs’ phase rule, there is a long tradition of reformulating the simple statement of the rule. The leading idea is to rewrite the rule with a term for the number of substances actually present and to introduce additional terms making explicit the various kinds of restrictions which in the original formulation are taken to be incorporated into Gibbs’ notion of the number of independent substances. Although the (...) number of independent substances cannot in general be interpreted as the number of substances actually present, it is not an entirely derivative concept as the authors of the reformulations sometimes seem to presuppose. In particular, it is doubtful whether the number of substances actually present is a clearly delimited concept which can be determined prior to the application of the phase rule. In that case, the phase rule provides a useful source of information for the determination of the number and nature of the substances actually present in a mixture which should be properly reflected in an adequate interpretation of Gibbs’ notion of independent substances. For this purpose, I propose a mereological interpretation of the way independent substances are related to the substances actually present which makes sense of the fact that the former are not uniquely fixed but can be chosen from the latter in several ways. (shrink)

I present two relatively independent sets of remarks on common causes and the violation of Bell inequalities in algebraic quantum field theory. The first set of remarks concerns the possibility of reconciling Reichenbachian ideas on common causes with quantum field theory in the face of an already known difficulty: the event shown to satisfy statistical relations for being the common cause of two correlated events has been associated with the union, rather than the intersection, of the backward light cones of (...) the correlated events. I explore a way of overcoming this difficulty by considering the common cause to be a conjunction of suitably located events. But I show that this line of thought too is beset with interpretational problems. My second set of remarks concerns the type of inequality one may derive from the common-common cause hypothesis: I argue, on grounds of interpretation, that the Clauser-Horne type, and not the Bell type, of inequalities emerge more naturally in this context. (shrink)

Abner Shimony argues that degrees of belief satisfy the axioms of probability because their epistemic goal is to match estimates of objective probabilities. Because the estimates obey the axioms of probability, degrees of belief must also obey them to reach their epistemic goal. This calibration argument meets some objections, but with a few revisions it can surmount those objections. It offers a good alternative to the Dutch book argument for compliance with the probability axioms. The defense of Shimony's calibration argument (...) examines rational pursuit of an epistemic goal, introduces strength of evidence and its measurement, and distinguishes epistemic goals and functions. (shrink)

In the present paper, we defend an inferential account both of explanation and scientific modelling. Our account is “comprehensive” in the sense that we assume a pragmatic perspective that tries to capture the intrinsic versatility scientific models and explanations may adopt in the course of scientific discourse. This inferential-pragmatic view is essentially inspired by the work of Robert Brandom in the philosophy of language (see Brandom 1994 and 2000), but takes elements from other authors, mainly from argumentation theory and epistemology. (...) As many philosophers of science that favour an inferential perspective, we see scientific models as inferential tools that help to extract inferences about the target in relation to specific goals. In this sense, models can be understood as consisting of sets of interconnected commitments and inferential norms allowing us to explaining and predicting phenomena in a relevant way (we develop this in de Donato and Zamora-Bonilla 2009). Likewise, explanation can be seen as a particular form of speech act understood according to a pragmatic-inferential view that allows to capturing the versatility of explanation. This is our main goal in the present paper. (shrink)