« Il valore delle leggi statistiche nella fisica e nelle scienze sociali » est le seul article d'Ettore Majorana qui ne soit pas de science mais sur la science. Il critique le déterminisme classique au nom du caractère intrinsèquement probabilitaire des lois en mécanique quantique et en sciences sociales entre lesquelles il établit une analogie formelle. Nous analysons son argumentation sur les plans métaphysique, physique et sociologique, avant d’évaluer la pertinence de cette épistémologie transversale.

The relatively recent trend seems to be to move away from General Philosophy of Science and towards the philosophies of the individual sciences and to relocate whatever content GPoS is supposed to have to the philosophies of the sciences. I argue that scepticism or pessimism about the prospects of GPoS is unwarranted. I also argue that there can be no philosophies of the various sciences without GPoS. Defending these two claims is the main target of this chapter. I will show, (...) however, that there is osmosis between GPoS and the Philosphies of the Sciences and that this osmosis is grounded on what I will call‘Science in general’ and the two important functions GPoS plays vis-à-vis Science-in-general: an explicative function and a critical function. (shrink)

Much of the focus on Poincaré’s philosophy of science has been on the notion of convention, a crucial concept that has become distinctive of his position. However, other notions have received much less attention. That is the case of verifiable hypotheses. This kind of hypotheses seems to be constituted from the generalization of several observable facts. So, in order to understand what these hypotheses are, we need to know what a fact to Poincaré is. He divides facts into brute and (...) scientific facts. The characterization of this duality is not trivial at all, and leads us to the following questions that we will discuss in this paper: which the part of construction that exists in a scientific fact and which the part of translation, that is, what remains from the brute fact in the scientific one?; and when we conceive a generalized hypothesis, are we supposed to do it from scientific or from brute facts? The clarification of these questions could lead to distinguish the part of construction and the part of translation in the first steps of science, which is essential to get a better understanding of Poincaré’s conception of science. (shrink)

In the introduction to his famous book, La Science et l’hypothèse, Poincaré remarks on the necessary role and legitimacy of hypotheses. He establishes a triple classification of hypotheses, dividing them into verifiable, useful, and apparent. However, in chapter 9, entitled ‘Les hypothèses en physique’, he gives a slightly different triadic classification: natural hypotheses, indifferent hypotheses, and real generalizations. The origin of this second classification is a lecture given at the International Congress of Physics, Paris, 1900. What are the similarities and (...) differences between these two classifications? My main purpose is to provide a possible equivalence between the two classifications in order to clarify the role of hypotheses in Poincaré’s epistemology of natural science. The discussion will be based on the two fundamental texts mentioned above and on the contrast between Poincaré’s use of the notion of hypothesis and that of some of his contemporaries. (shrink)

Guest Editors’ introduction to the Monographic Section.

This paper aims at understanding the concept of convention in mechanics as a notion transferred from the field of jurisprudence. This enables us to clarify it as a new epistemic category having a pertinent role in the transformation of mechanics in the nineteenth century. Such understanding permits a separation from linguistic and arbitrary conventions, thus highlighting its epistemic features and not transforming fundamental principles into mere arbitrary agreements. After addressing the main references in the literature discussing the role of convention (...) in mechanics, we analyze its classical use as a concept originating from law. Then we explain its use by Carl G. Jacobi, Ferdinand F. Reech, and J. Henri Poincaré. Here we also show how their uses conform to the features analyzed regarding conventions in jurisprudence. Finally, we try to explain how the use of this concept, among other factors, contributed to the transformation of mechanics. (shrink)

The purpose of this paper is to demonstrate the usefulness of the concept of possibility , and not merely that of actuality , for an inquiry into the bodily constitution of experience. The paper will study how the possibilities of action that may (or may not) be available to the subject help to shape the meaning attributed to perceived objects and to the situation occupied by the subject within her environment. This view will be supported by reference to empirical evidence (...) provided by recent and current research on the perceptual estimation of distances and the effects brought about by the use of a tool on the organisation of our perceived immediate space. (shrink)

In French mechanical treatises of the nineteenth century, Newton’s second law of motion was frequently derived from a relativity principle. The origin of this trend is found in ingenious arguments by Huygens and Laplace, with intermediate contributions by Euler and d’Alembert. The derivations initially relied on Galilean relativity and impulsive forces. After Bélanger’s Cours de mécanique of 1847, they employed continuous forces and a stronger relativity with respect to any commonly impressed motion. The name “principle of relative motions” and the (...) very idea of using this principle as a constructive tool were born in this context. The consequences of Poincaré’s and Einstein’s awareness of this approach are analyzed. Lastly, the legitimacy and significance of a relativity-based derivation of Newton’s second law are briefly discussed in a more philosophical vein. (shrink)

In a recent article Merritt has claimed that current observational data provide “severe tests” falsifying the standard cosmological model. Based on Popper’s idea of conventionalism, he concludes that the introduction of some essential components of the standard cosmological model—including dark matter and dark energy—are a consequence of conventionalist stratagems. In this article, I provide more recent discoveries and discussions showing that the standard cosmological model is not built on any conventionalist stratagem.

Das Problem, unter welchen Bedingungen eine Hypothese oder Theorienmodifikation als methodologisch akzeptabel gilt, wird in der wissenschaftstheoretischen Tradition als die Frage des Ad-Hoc-Charakters von Hypothesen diskutiert. Das gleichartige Problem tritt aber auch in Lakatos' Methodologie wissenschaftlicher Forschungsprogramme auf, welche von methodologisch zulässigen Theorienänderungen die Vorhersage 'neuer Tatsachen' verlangt. Über diesen Begriff der neuen Tatsache und damit der Adäquatheitsbedingungen für wissenschaftliche Erklärungen hat sich eine weitgefächerte Debatte entsponnen. In diesem Papier wird der Versuch unternommen, die Forderung der unabhängigen Testbarkeit einer Hypothese, (...) welche im Rahmen der Diskussion des Ad-hoc-Charakters von Hypothesen eine wichtige Rolle spielt, auch für die Frage der Spezifizierung von 'neuen Tatsachen' fruchtbar zu machen. Ich argumentiere zugunsten der Bedingung, daß eine Hypothese als methodologisch akzeptabel gelten sollte, wenn sie zumindest zwei unabhängige Tatsachen erklärt. Ein derartiger Ansatz verlangt die Kennzeichnung dessen, was als 'eine Tatsache' zu gelten hat. Die Schwierigkeit einer derartigen Kennzeichnung ist ein notorisches Problem jedes Kriteriums, das auf unabhängige Testbarkeit zielt. Eine Klärung dieses Problems wird über das Konzept der empirischen Generalisierung versucht. Als 'eine Tatsache' im methodologischen Sinne gilt demnach ein gesetzmäßiger Zusammenhang zwischen zwei Meßgrößen. Dies erlaubt weiterführend eine Klärung des Problems, was methodologisch als 'ein Experiment' zu werten ist, d. h. was als Reproduktion desselben und was als andersartiges Experiment gelten soll. Mit Hilfe dieser Klärungen wird unter anderem der Ad-hoc-Charakter der Lorentzschen Kontraktionshypothese sowie das Problem der Gleich- oder Verschiedenartigkeit von Michelson-Morley- und Kennedy-Thorndike-Experiment untersucht. (shrink)

The aim of this paper is to discuss the relation between the observation basis and the theoretical principles of General Relativity. More specifically, this relation is analyzed with respect to constructive axiomatizations of the observation basis of space-time theories, on the one hand, and in attempts to complete them, on the other. The two approaches exclude one another so that a choice between them is necessary. I argue that the completeness approach is preferable for methodological reasons.

The paper addresses the question of the nature and limits of philosophical thought experiments. On the one hand, experimental philosophers are right to claim that we need much more laboratory work in order to have more reliable thought experiments, but on the other hand a naturalism that is too radical is incapable of clarifying the peculiarity of thought experiments in philosophy. Starting from a historico-critical reconstruction of Kant’s concept of the “experiments of pure reason”, this paper outlines an account of (...) thought experiments in philosophy that tries to reconcile the thesis of a principled difference between scientific and philosophical TEs with the position of a methodological naturalism that does not admit any difference in kind between the methods of science and of philosophy. (shrink)

The physicist's conception of space-time underwent two major upheavals thanks to the general theory of relativity and quantum mechanics. Both theories play a fundamental role in describing the same natural world, although at different scales. However, the inconsistency between them emerged clearly as the limitation of twentieth-century physics, so a more complete description of nature must encompass general relativity and quantum mechanics as well. The problem is a theorists' problem par excellence. Experiment provide little guide, and the inconsistency mentioned above (...) is an important problem which clearly illustrates the intermingling of philosophical, mathematical, and physical thought. In fact, in order to unify general relativity with quantum field theory, it seems necessary to invent a new mathematical framework which will generalise Riemannian geometry and therefore our present conception of space and space-time. Contemporary developments in theoretical physics suggest that another revolution may be in progress, through which a new kind of geometry may enter physics, and space-time itself can be reinterpreted as an approximate, derived concept. The main purpose of this article is to show the great significance of space-time geometry in predetermining the laws which are supposed to govern the behaviour of matter, and further to support the thesis that matter itself can be built from geometry, in the sense that particles of matter as well as the other forces of nature emerges in the same way that gravity emerges from geometry. Scientific research is not a process of steady accumulation of absolute truths, which has culminated in present theories, but rather a much more dynamic kind of process in which there are no final theoretical concepts valid in unlimited domains. (David Bohm). (shrink)

According to Kant, the axioms of intuition, i.e. space and time, must provide an organization of the sensory experience. However, this first orderliness of empirical sensations seems to depend on a kind of faculty pertaining to subjectivity, rather than to the encounter of these same intuitions with the real properties of phenomena. Starting from an analysis of some very significant developments in mathematical and theoretical physics in the last decades, in which intuition played an important role, we argue that nevertheless (...) intuition comes into play in a fundamentally different way to that which Kant had foreseen: in the form of a formal or “categorical” yet not sensible intuition. We show further that the statement that our space is mathematically three-dimensional and locally Euclidean by no means follows from a supposed a priori nature of the sensible or subjective space as Kant claimed. In fact, the three-dimensional space can bear many different geometrical and topological structures, as particularly the mathematical results of Milnor, Smale, Thurston and Donaldson demonstrated. On the other hand, it has been stressed that even the phenomenological or perceptual space, and especially the visual system, carries a very rich geometrical organization whose structure is essentially non-Euclidean. Finally, we argue that in order to grasp the meaning of abstract geometric objects, as n-dimensional spaces, connections on a manifold, fiber spaces, module spaces, knotted spaces and so forth, where sensible intuition is essentially lacking and where therefore another type of mathematical idealization intervenes, we need to develop a new form of intuition. (shrink)

The history and philosophy of science are destined to play a fundamental role in an epoch marked by a major scientific revolution. This ongoing revolution, principally affecting mathematics and physics, entails a profound upheaval of our conception of space, space–time, and, consequently, of natural laws themselves. Briefly, this revolution can be summarized by the following two trends: by the search for a unified theory of the four fundamental forces of nature, which are known, as of now, as gravity, electromagnetism, and (...) strong and weak nuclear forces; by the search for new mathematical concepts capable of elucidating and therefore explaining such a relationship. In fact, the first search is essentially dependent on the second; that is to say, that in order for a new theory of physics to come to light, the development of a deeper geometric theory capable of explaining the structure of space–time on a quantum scale appears to be necessary. On careful consideration, we notice that both of these developments converge in the direction of a unitary and fundamental tendency of modern science—which is the geometrization of theoretical physics and of natural sciences. This new emergent situation carries within it a profound conceptual change, affecting the way in which relations are conceived of, first and foremost, between mathematics and physics. This new paradigm can be summed up by the intimately interdependent points: the immense variety of physical phenomena and of natural forms follows from the equally infinite variety of geometric and topological objects that can be made out in space and from which space is made up; the second point, which ensues from the former one and which is of great historical and epistemological significance, is that mathematics is involved in rather than applied to phenomena. In other words, phenomena are effects that emerge from the geometrical structure of space–time. There is no doubt that this new conception of the relationship between the universe of mathematical ideas and objects and the world of natural phenomena is the true scientific revolution of our century, of great conceptual importance, and consequently, capable of changing our view of science and of nature at one and the same time. It is all at once of a scientific, philosophical and aesthetic order. (shrink)

According to a common philosophical intuition, the deep nature of things is hidden from us, and the world as we know it through perception and science is, just like a dream, shadows, or a computer simulation, somehow shallow and lacking in reality. This “intuition of unreality” clashes with a strong, but perhaps more naive, intuition to the effect that the world as we know it seems perfectly real. Shadows, dreams, or informational structures appear too unreal to be identical to the (...) world as we know it! This clash between the two intuitions forms the basis of the “problem of reality.” In the late nineteenth century psychiatrists encountered patients they referred to as “metaphysician doubters” who constantly questioned the reality of the world. This essay draws on studies of these patients in order to reject, and indeed diagnose, the intuition of unreality and recent metaphysical doctrines drawing on it, such as structuralism, digitalism, and virtual realism. (shrink)

In 1870, Hermann von Helmholtz criticized the Kantian conception of geometrical axioms as a priori synthetic judgments grounded in spatial intuition. However, during his dispute with Albrecht Krause (Kant und Helmholtz über den Ursprung und die Bedeutung der Raumanschauung und der geometrischen Axiome. Lahr, Schauenburg, 1878), Helmholtz maintained that space can be transcendental without the axioms being so. In this paper, I will analyze Helmholtz’s claim in connection with his theory of measurement. Helmholtz uses a Kantian argument that can be (...) summarized as follows: mathematical structures that can be defined independently of the objects we experience are necessary for judgments about magnitudes to be generally valid. I suggest that space is conceived by Helmholtz as one such structure. I will analyze his argument in its most detailed version, which is found in Helmholtz (Zählen und Messen, erkenntnistheoretisch betrachtet 1887. In: Schriften zur Erkenntnistheorie. Springer, Berlin, 1921, 70–97). In support of my view, I will consider alternative formulations of the same argument by Ernst Cassirer and Otto Hölder. (shrink)

Eger's contribution towards a reapprochment of Hermeneutics, Science and Science Education is very welcome. His focus on the problem of misconceptions is relevant. All the same in our opinion some not minor points need a clarification. We will try to argue that: a) Hermeneutics cannot be reduced to a semantical interpretation of science texts; its phenomenological aspects have to be taken in account. b) Science has an unavoidable historical dimension; original papers and advanced textbooks are the real depositaries of scientific (...) research. Standard textbooks are a caricature not worth it of a hermeneutical analysis. c) A parallelism can be traced between two dicothomies: the lifeworld of hermeneutics and the scienceworld of epistemology on one side and the extraordinary and the normal science on the other. d) For an overcoming of the misconceptions' problem we propose that the previous dicothomies be bridged through a hermeneutical phenomenological approach to science education that stresses the alternative, historical interpretations of natural phenomena. (shrink)

According to a common belief concerning the Mach-Boltzmann debate on atoms, the new experiments performed in microphysics at the turn of the 19th and 20th centuries confirmed Boltzmann's atomic hypothesis and disproved Mach's anti-atomic view. This paper intends to show that this belief is partially unjustified. Mach's view on atoms consists in fact of different kinds of arguments. While the new experiments in microphysics refute indeed his scientific arguments against the atomic hypothesis, his epistemological arguments are unaffected. In this regard, (...) Mach's epistemological approach remains relevant for today's discussion on the status of the notion of atom. (shrink)

One of the most important contributions of A. Church to logic is his invention of the lambda calculus. We present the genesis of this theory and its two major areas of application: the representation of computations and the resulting functional programming languages on the one hand and the representation of reasoning and the resulting systems of computer mathematics on the other hand.

In this chapter I investigate the prospects of integrated history and philosophy of science, by examining how philosophical issues raised by “hidden entities”, entities that are not accessible to unmediated observation, can enrich the historical investigation of their careers. Conversely, I suggest that the history of those entities has important lessons to teach to the philosophy of science. Hidden entities have played a crucial role in the development of the natural sciences. Despite their centrality to past scientific practice, however, several (...) of them (e.g., phlogiston, caloric, and the ether) turned out to be fictitious. For this reason, they have figured prominently in recent debates on scientific realism. The issues I explore in this paper are entangled with those debates. I argue that our understanding of hidden entities and their role in experimental practice can be enhanced by adopting an integrated historical-cum-philosophical approach. On the one hand, philosophical reflection on the reality of those entities has a lot to gain by examining historically how they were ntroduced and investigated. On the other hand, the historical reconstruction of the careers of those entities may profit from philosophical reflection on their existence. (shrink)

According to a common philosophical intuition, the deep nature of things is hidden from us, and the world as we know it through perception and science is somehow shallow and lacking in reality. For all we knwo, the intuition goes, we could be living in a cave facing shadows, in a dream or even in a computer simulation, This “intuition of unreality” clashes with a strong, but perhaps more naive, intuition to the effect that the world as we know it (...) seems perfectly real. Shadows, dreams, or informational structures appear too unreal to be identical to the world as we know it! This clash between the two intuitions forms the basis of the "problem of reality." At the turn of the nineteenth century psychiatrists encountered patients they referred to as “metaphysician doubters” who constantly questioned the reality of the world. This essay draws on the study of these patients to reject, and indeed diagnose, the intuition of unreality and recent metaphysical doctrines drawing on it, such as structuralism, digitalism, and virtual realism. (shrink)

In an earlier article on this journal I argued that the problem of empirical underdetermination can for the largest part be solved by theoretical virtues, and for the remaining part it can be tolerated. Here I confront two further challenges to scientific realism based on underdetermination. First, there are four classes of theories which may seem to be underdetermined even by theoretical virtues. Concerning them I argue that (i) theories produced by trivial permutations and (ii) “equivalent descriptions” are compatible with (...) the truth of standard theories; instead (iii) “as if” versions of standard theories are much worse from the point of view of theoretical virtues; finally (iv) mathematically intertranslatable theories either may become empirically decidable in the future, or can be discriminated by theoretical virtues, or realists may simply plead ignorance about their claims. Secondly, I consider Stanford’s underdetermination with respect unconceived alternatives, arguing that it essentially relies on the pessimistic meta-induction from the falsity of all past theories. Therefore, it can be resisted by (a) considering the radical advancement of present with respect to past science, and (b) arguing with selective realism that past successful theories, even if false, always included some true components. (shrink)

These are the introduction chapters to the forthcoming collection of essays published by Springer (Synthese Library) and entitled Probabilities, Causes and Propensities in Physics.

The essays in this volume concern the points of intersection between analytic philosophy and the philosophy of the exact sciences. More precisely, it concern connections between knowledge in mathematics and the exact sciences, on the one hand, and the conceptual foundations of knowledge in general. Its guiding idea is that, in contemporary philosophy of science, there are profound problems of theoretical interpretation-- problems that transcend both the methodological concerns of general philosophy of science, and the technical concerns of philosophers of (...) particular sciences. A fruitful approach to these problems combines the study of scientific detail with the kind of conceptual analysis that is characteristic of the modern analytic tradition. Such an approach is shared by these contributors: some primarily known as analytic philosophers, some as philosophers of science, but all deeply aware that the problems of analysis and interpretation link these fields together. (shrink)

Debates concerning the units and levels of selection have persisted for over fifty years. One major question in this literature is whether units and levels of selection are genuine, in the sense that they are objective features of the world, or merely reflect the interests and goals of an observer. Scientists and philosophers have proposed a range of answers to this question. This Element introduces this literature and proposes a novel contribution. It defends a realist stance and offers a way (...) of delineating genuine levels of selection by invoking the notion of a functional unit. (shrink)

The Ramsey-sentence H* of any hypothesis H is shown to be a synthetic proposition containing mathematics as a finite component. Far from being quasi-tautological, H* proves to have as much physical content as H itself.

In this paper I argue that inconsistencies in scientific theories may arise from the type of causality relation they—tacitly or explicitly—embody. All these seemingly different causality relations can be subsumed under a general strategy developed to defeat the paradoxes which inevitably occur in our experience of the real. With respect to this, scientific theories are just a subclass of the larger class of metaphysical theories, construed as theories that attempt to explain a (part of) the world consistently. All metaphysical theories (...) share a common structural backbone specificially designed to defeat paradoxes, their often wildly diverging ontological claims notwithstanding. This common structure shapes the procedures which govern the invention of ideas in the context of such theories, by codifying some onto-logical a priori assumptions regarding the consistency of reality into its bare conceptual framework. Causality plays a key rôle here, because it implies conservation of identity, itself a far from simple notion. It imposes strong demands on the universalising power of the theories concerned. These demands are often met by the introduction of a metalevel which encompasses the notions of ‘system’ and ‘lawful behaviour’. In classical mechanics, the division between universal and particular leaves its traces in the separate treatment of cinematics and dynamics. The fundamental backbone’s specific gestalt thus functions as a theory’s individual signature and paves the way to a comparative historical approach towards their study. An important part of my paper therefore explores the strong connections between paradoxes as they appear and are dealt with in ancient philosophy and their re-appearance in early modern natural philosophy and science. This analysis is applied to the mechanical theories of Newton and Leibniz, with some surprising results. (shrink)

Debido a la historicidad de la razón, más que inventariar sus principales conceptos en un momento dado nos interesa estudiar el proceso de su formación y fijación. En este artículo se ilustra ese proceso con ejemplos tomados de la historia de la física. El primer ejemplo concierne a la subordinación en el siglo XVII de los fenómenos archiconocidos de la caída libre y el movimiento de los planetas a un concepto nuevo; los restantes, tomados de la electrodinámica del siglo XIX (...) y la microfísica y la cosmología del siglo XX, ilustran el juego mutuo de tales conceptos con novedades empíricas que en algunos casos los provocan, en otros los realizan. (shrink)

Beaucoup de « géomètres » du XIXe siècle - Bernhard Riemann, Hermann von Helmholtz, Felix Klein, Riccardo De Paolis, Mario Pieri, Henri Poincaré, Federigo Enriques, et autres - ont joué un rôle important dans la discussion sur les fondements des mathématiques. Mais, contrairement aux idées d'Euclide, ils n'ont pas identifié «l'espace physique» avec« l'espace de nos sens». Partant de notre expérience dans l'espace, ils ont cherché à identifier les propriétés les plus importantes de l'espace et les ont posées à la (...) base de la géométrie. C'est sur la connaissance active de l'espace que les axiomes de la géométrie ont été élaborés ; ils ne pouvaient donc pas être a priori comme ils le sont dans la philosophie kantienne. En outre, pendant la dernière décade du siècle, certains mathématiciens italiens - De Paolis, Gino Fano, Pieri, et autres - ont fondé le concept de nombre sur la géométrie, en employant des résultats de la géométrie projective. Ainsi, on fondait l'arithmétique sur la géométrie et non l'inverse, comme David Hilbert a cherché à faire quelques années après, sans succès. (shrink)

I trace the development of arguments for the consistency of non-Euclidean geometries and for the independence of the parallel postulate, showing how the arguments become more rigorous as a formal conception of geometry is introduced. I analyze the kinds of arguments offered by Jules Hoüel in 1860-1870 for the unprovability of the parallel postulate and for the existence of non-Euclidean geometries, especially his reaction to the publication of Beltrami’s seminal papers, showing that Beltrami was much more concerned with the existence (...) of non-Euclidean objects than he was with the formal consistency of non-Euclidean geometries. The final step towards rigorous consistency proofs is taken in the 1880s by Henri Poincaré. It is the formal conception of geometry, stripping the geometric primitive terms of their usual meanings, that allows the introduction of a modern fully rigorous consistency proof. (shrink)

After a description of the method of mathematics and empirical sciences, brief but explicit enough to show their limits with philosophical and theological reflection, I comment the harmonic relations of mutual help among them, and also, unfortunately, the historical occasions in which these limits have been trespassed. And after a fast view of the image of the world–matter and life–presented to us by nowadays established science, I recall the main items of opposition to faith posed by science, although sometimes just (...) promised science. I show that today’s science is in complete harmony with faith and that these items only show the opposition with faith of the materialistic philosophical points of view of some of the divulgators, not really opposition of established science. Finally we discuss that Aristotelian hylomorphism, posing form in matter, is more suited to dialog with present science than philosophies of Kantian inspiration posing form only in our knowledge or in our scientific theories. (shrink)

The reflection on the preconditions and evolution of science has played a decisive role in the development of Ernst Cassirer's philosophy, contributing to its functional and thus inherently pluralistic and holistic view of knowledge. To present Cassirer's conception of physics as an open symbolic formation enables us to reveal and study the radical features of his epistemological model: (1) the fundamental process of generating sense-units and meaning in its constitutive character for each attempt of objectification, (2) its driving and structuring (...) dynamics that touches and transforms all elements of knowledge, the a priori included, (3) the strategies of justification that allow maintaining the claim of truthfulness in spite the fact that Cassirer's open model integrates contingency and transitoriness as an inherent part of knowledge. It thus becomes clear that Cassirer's term 'symbol' cannot be reduced to its habitual representational acceptation, for its key theoretical function is to overcome the inconsistencies of dualistic epistemological models. It is this re-orientation, a kind of 'second Copernican revolution', that allows Cassirer to go beyond traditional dichotomies and to propose a larger frame in which to appreciate the diversity of human understanding. (shrink)

Founding our analysis on the Geneva-Brussels approach to the foundations of physics, we provide a clarification and classification of the key concept of observation. An entity can be observed with or without a scope. In the second case, the observation is a purely non-invasive discovery process; in the first case, it is a purely invasive process, which can involve either creation or destruction aspects. An entity can also be observed with or without a full control over the observational process. In (...) the latter case, the observation can be described by a symmetry breaking mechanism, through which a specific deterministic observational process is selected among a number of potential ones, as explained in Aerts’ hidden measurement approach. This is what is called a product test, or product observation, whose consequences are that outcomes can only be predicted in probabilistic terms, as it is the case in typical quantum measurements. We also show that observations can be about intrinsic (stable) properties of the observed entity, or about relational (ephemeral) properties between the observer and observed entities; also, they can be about intermediate properties, neither purely classical, nor purely quantum. Our analysis allows us to propose a general conceptual characterization of quantum measurements, as observational processes involving three aspects: (1) product observations, (2) pure creation aspects and (3) ephemeral relational properties. We also discuss the important concept of non-spatiality and emphasize some of the differences and similarities between quantum and classical/relativistic observations. (shrink)

In this article, we redefine classical notions of theory reduction in such a way that model-theoretic preferential semantics becomes part of a realist depiction of this aspect of science. We offer a model-theoretic reconstruction of science in which theory succession or reduction is often better - or at a finer level of analysis - interpreted as the result of model succession or reduction. This analysis leads to 'defeasible reduction', defined as follows: The conjunction of the assumptions of a reducing theory (...) T with the definitions translating the vocabulary of a reduced theory T' to the vocabulary of T, defeasibly entails the assumptions of reduced T'. This relation of defeasible reduction offers, in the context of additional knowledge becoming available, articulation of a more flexible kind of reduction in theory development than in the classical case. Also, defeasible reduction is shown to solve the problems of entailment that classical homogeneous reduction encounters. Reduction in the defeasible sense is a practical device for studying the processes of science, since it is about highlighting different aspects of the same theory at different times of application, rather than about naive dreams concerning a metaphysical unity of science. (shrink)

A conception of probability that can be traced back to Johannes von Kries is introduced: the “Spielraum” or range conception. Its close connection to the so-called method of arbitrary functions is highlighted. Possible interpretations of it are discussed, and likewise its scope and its relation to certain current interpretations of probability. Taken together, these approaches form a class of interpretations of probability in its own right, but also with its own problems. These, too, are introduced, discussed, and proposals in response (...) to them are surveyed, some of which also go back to von Kries. (shrink)

Presentism is, roughly, the metaphysical doctrine that maintains that whatever exists, exists in the present. The compatibility of presentism with the theories of special and general relativity was much debated in recent years. It has been argued that at least some versions of presentism are consistent with time-orientable models of general relativity. In this paper we confront the thesis of presentism with relativistic physics, in the strong gravitational limit where black holes are formed. We conclude that the presentist position is (...) at odds with the existence of black holes and other compact objects in the universe. A revision of the thesis is necessary, if it is intended to be consistent with the current scientific view of the universe. (shrink)

Hume famously warned us that the ‘[The] ultimate springs and principles are totally shut up from human curiosity and enquiry’. Or, again, Newton: ‘Hitherto I have not been able to discover the cause of these properties of gravity … and I frame no hypotheses.’ Aristotelian science was concerned with just such questions, the specification of occult qualities, the real essences that answer the question What is matter, etc?, the preoccupation with circular definitions such as dormative virtues, and so on. The (...) rise of modern science is usually seen as a break with the sterility of Aristotelianism, so what exactly is it that modern science does discover, if it is not the essential nature of matter, of force, of energy, of space and time? A famous answer was provided by Poincaré: ‘The true relations between these real objects are the only reality we can attain.’ This is often regarded as the manifesto of so-called structural realism, as espoused in recent years by John Worrall, for example ). In response to the arguments of Larry Laudan against convergent realism, Worrall points to the continuity in the formal relations between elements of reality expressed by mathematical equations, while the intrinsic nature of these elements of reality gets constantly revised. (shrink)

The object of this article is to show a certain proximity of Duhem to Poincaré in his first philosophical reflections. I study the relationships between the scientific practices of the two scholars, the contemporary theoretical context and their reflections. The first part of the article concerns the changes in epistemological consensus at the turn of the century. The second part will be devoted to Poincaré's reflections on the status of physical geometries and physical theories, as they appear in his texts (...) written around 1890. Then I analyze the first reflections of Pierre Duhem on physical theory, in particular his thesis of the hypothetical/symbolic character of physical theories and his criteria for selecting good theories, partly associated with his ideal of physical theory; the whole set of considerations, highlighting the Poincarean inspiration. (shrink)

Kantian philosophy of space, time and gravity is significantly affected in three ways by particle physics. First, particle physics deflects Schlick’s General Relativity-based critique of synthetic a priori knowledge. Schlick argued that since geometry was not synthetic a priori, nothing was—a key step toward logical empiricism. Particle physics suggests a Kant-friendlier theory of space-time and gravity presumably approximating General Relativity arbitrarily well, massive spin-2 gravity, while retaining a flat space-time geometry that is indirectly observable at large distances. The theory’s roots (...) include Seeliger and Neumann in the 1890s and Einstein in 1917 as well as 1920s–1930s physics. Such theories have seen renewed scientific attention since 2000 and especially since 2010 due to breakthroughs addressing early 1970s technical difficulties. Second, particle physics casts additional doubt on Friedman’s constitutive a priori role for the principle of equivalence. Massive spin-2 gravity presumably should have nearly the same empirical content as General Relativity while differing radically on foundational issues. Empirical content even in General Relativity resides in partial differential equations, not in an additional principle identifying gravity and inertia. Third, Kant’s apparent claim that Newton’s results could be known a priori is undermined by an alternate gravitational equation. The modified theory has a smaller symmetry group than does Newton’s. What Kant wanted from Newton’s gravity is impossible due its large symmetry group, but is closer to achievable given the alternative theory. (shrink)

An overlap between the general relativist and particle physicist views of Einstein gravity is uncovered. Noether's 1918 paper developed Hilbert's and Klein's reflections on the conservation laws. Energy-momentum is just a term proportional to the field equations and a "curl" term with identically zero divergence. Noether proved a \emph{converse} "Hilbertian assertion": such "improper" conservation laws imply a generally covariant action. Later and independently, particle physicists derived the nonlinear Einstein equations assuming the absence of negative-energy degrees of freedom for stability, along (...) with universal coupling: all energy-momentum including gravity's serves as a source for gravity. Those assumptions imply that the energy-momentum is only a term proportional to the field equations and a symmetric curl, which implies the coalescence of the flat background geometry and the gravitational potential into an effective curved geometry. The flat metric, though useful in Rosenfeld's stress-energy definition, disappears from the field equations. Thus the particle physics derivation uses a reinvented Noetherian converse Hilbertian assertion in Rosenfeld-tinged form. The Rosenfeld stress-energy is identically the canonical stress-energy plus a Belinfante curl and terms proportional to the field equations, so the flat metric is only a convenient mathematical trick without ontological commitment. Neither generalized relativity of motion, nor the identity of gravity and inertia, nor substantive general covariance is assumed. The more compelling criterion of lacking ghosts yields substantive general covariance as an output. Hence the particle physics derivation, though logically impressive, is neither as novel nor as ontologically laden as it has seemed. (shrink)