Marco Buzzoni

Nella sua straordinaria opera scientifica, Franco Selleri si è sempre opposto alla rinuncia alla comprensione della struttura della realtà e della natura degli oggetti fisici, che egli considera come l’elemento caratterizzante delle principali teorie della fisica del Novecento e che è stata stigmatizzata da Karl Popper come tesi della “fine della strada in fisica”. Sin dalla fine degli anni ’60, egli ha sviluppato quella riflessione critica nei confronti delle teorie fondamentali della fisica moderna, in particolar modo della teoria delle particelle elementari e della meccanica quantistica, e in un secondo tempo delle teorie relativistiche, che contraddistingue il suo programma di ricerca. Nel corso della sua intensa e infaticabile attività scientifica, Selleri è entrato in proficuo contatto con molti grandi fisici e filosofi della scienza, instaurando un intenso dialogo critico con Louis de Broglie, John Bell e Karl Popper. Le sue originali e non convenzionali ricerche lo hanno portato a risultati significativi non solo nell’ambito dei fondamenti della fisica, ma anche della storia e della filosofia della fisica. Per questo abbiamo voluto dedicare un numero speciale di Isonomia al nostro impareggiabile amico e collega, sia per la sua passione instancabile e la sua profonda conoscenza dei fondamenti formali, concettuali e filosofici delle teorie della fisica contemporanea, sia e forse ancor più come maestro di una prospettiva perennemente critica che egli ha sempre seguito e proposto con particolare rigore ed estrema determinazione.

The purpose of this article is to examine two important issues concerning the agency theory of causality: the charge of anthropomorphism and the relation of simultaneous causation. After a brief outline of the agency theory, sections 2–4 contain the refutation of the three main forms in which the charge of anthropomorphism is to be found in the literature. It will appear that it is necessary to distinguish between the subjective and the objective aspect of the concept of causation. This will lead, in section 5, to contrast two kinds of anthropomorphism, one which has been rightly rejected by modern science and one which is fully compatible with the objective reality of the causal processes. Finally, section 6 will apply the preceding considerations to simultaneous causation. On the one hand, in a basic sense, there can be no simultaneous causal relations. On the other hand, simultaneous causation arises when we consider the natural change by abstracting from the agent and from her/his projects of interven..

Thought experiments de facto play many different roles in biology: economical, ethical, technical and so forth. This paper, however, is interested in whether there are any distinctive features of biological TEs as such. The question may be settled in the affirmative because TEs in biology have a function that is intimately connected with the epistemological and methodological status of biology. Peculiar to TEs in biology is the fact that the reflexive, typically human concept of finality may be profitably employed to discover mechanical-experimental causal relations in all living beings—with the obvious caveat that we do not hypostatise and interpret this concept as an ontological quality, since this would land one in an implicitly animistic, pre-Galilean view of nature. From a methodical point of view, the concept of finality is an essential assumption as well as a powerful heuristic tool in the practice of biology, that is, in the investigation of living beings in an intersubjectively testable and reproducible way

On the relation between experiment and thought experiment in the natural sciences. To understand the reciprocal autonomy and complementarity of thought and real experiment, it is necessary to distinguish between a ‘positive’ (empirical or formal) and a transcendental perspective. Empirically and formally, real and thought experiments are indistinguishable. However, from a reflexive-transcendental viewpoint thought experiment is at the same time irreducible and complementary to real experiment. This is due to the fact that the hypothetical-anticipatory moment is in principle irreducible to physical reality—even though it refers to physical reality and is bound with the empirical use of our understanding. The presence of counterfactuals is the condition of the possibility for thought experiments to become in principle real ones, by means of a series of technical realisations that gradually approximate the idealisations that they contain.

In the last decades it has become clear that medicine must find some way to combine its scientific and humanistic sides. In other words, an adequate notion of medicine requires an integrative position that mediates between the analytic-reductionist and the normative-holistic tendencies we find therein. This is especially important as these different styles of reasoning separate “illness” (something perceived and managed by the whole individual in concert with their environment) and “disease” (a “mechanical failure” of a biological element within the body). While the demand for an integrative view has typically been motivated by ethical concerns, we claim that it is also motivated, perhaps even more fundamentally, by epistemological and methodological reasons. Evidence-based bio-medicine employs experimental and statistical techniques which eliminate important differences in the ways that conscious humans evaluate, live with, and react to disease and illness. However, it is precisely these experiences that underpin the concepts and norms of bio-medicine. Humanistic disciplines, on the other hand, have the resources to investigate these experiences in an intersubjectively testable way. Medicine, therefore, cannot afford to ignore its nature as a human science; it must be concerned not only with disease and illness, but also with the ways in which patients as persons respond to malady. Insofar as attitudes and expectations influence the criteria of illness and disease, they must be studied as part of the genuine subject matter of medicine as a human science. In general, we urge that this is a necessary step to overcome today's trend to split evidence-based and clinical medicine.

All the powerful influences exertedby the subjective-interpersonal dimension onthe organic or technical-functional dimensionof sickness and health do not make anintersubjective test concerning medicaltherapeutic results impossible. Theseinfluences are not arbitrary; on the contrary,they obey laws that are de facto sufficientlystable to allow predictions and explanationssimilar to those of experimental sciences.While, in this respect, the rules concerninghuman action are analogous to the scientificlaws of nature, they can at any time be revokedby becoming aware of them. Law-like andreproducible regularities in the sciences ofman are by no means separated from a patient'spersonal-hermeneutic mediation. This makes itpossible for human beings to modify, improve orsometimes even entirely (or better almostentirely) suspend these psychological,sociological, ethnological, medical,regularities. For this reason the sciences ofman including medicine are under the obligationof constantly inspecting the continuingvalidity of the rules on which theirpredictions and explanations are based, namelyby indirect, statistical methods. Thisrequires a synergistic collaboration ofextra-clinical and clinical tests through whichmedicine can obtain a good level ofintersubjective testability.

The conventional interpretation that Pierre Duhem condemned outright any type of thought experiment in Ernst Mach’s sense should be, at least in large part, rejected. Although Duhem placed particular emphasis on the perils of thought experiments that Mach had overlooked or at least underestimated, he retained the core idea of Mach’s theory, according to which thought experiments cannot break free from the ultimate authority of real-world experiments. This similarity between Duhem’s and Mach’s views about thought experiments is not the only one. Just as there was in Duhem’s criticism of “expériences fictives” a tendency leading him to give voice to one of Mach’s basic empiricist claims, so also there was in Mach’s interpretation of thought experiments a tendency in the direction of Duhem’s conventionalism. If Mach’s and Duhem’s conceptions of thought experiments are compared, there results an importantly similar, although not identical, tension that should properly be taken into account in the more general comparison between Mach and Duhem.

The terms “perspectivism” and “perspectivalism” have been the focus of an intense philosophical discussion with important repercussions for the debate about the role of mechanisms in scientific explanations. However, leading exponents of the new mechanistic philosophy have conceded more than was necessary to the radically subjectivistic perspectivalism, and fell into the opposite error, by retaining not negligible residues of objectivistic views about mechanisms. In order to remove this vacillation between the subjective-cultural and the objective-natural sides of mechanisms, we shall raise the question about theory-ladenness over again and interpret it in its connection with the technical–experimental nature of scientific knowledge, as affirming the perspectival character of scientific knowledge: It is because of the character at once theory-laden and practice-laden, i.e. technique-laden, of our putting questions to nature that empirical reality must be investigated from particular perspectives: nature can be known scientifically only from a potentially infinite number of perspectives or theoretical points of view, concretely exemplified by mechanisms or experimental ‘machines’ that allow specific access to specific aspects of sensible reality.

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.

This paper replies to objections that have been raised against my operational-Kantian account of thought experiments by Fehige 2012 and 2013. Fehige also sketches an alternative Neo-Kantian account that utilizes Michael Friedman’s concept of a contingent and changeable a priori. To this I shall reply, first, that Fehige’s objections not only neglect some fundamental points I had made as regards the realizability of TEs, but also underestimate the principle of empiricism, which was rightly defended by Kant. Secondly, in opposition to what he states, my account does not differ in a very essential way from the empiricist solutions either as regards the power of TEs to predict something new about empirical reality, or as regards the criteria for telling apart good from bad TEs. Thirdly, in the light of the Kantian definition of the a priori, Friedman’s corresponding notion is contrary both to the spirit and to the letter of Kant’s philosophy; moreover, from a theoretical point of view, a material a priori is theoretically untenable since, counter to Friedman’s own intentions, it leads to relativism.

Why, for such a long time, has there been no Kantian point of view among the most influential theories about thought experiments? The primary historical reason – the main trends in the philosophy of science have always rejected the existence of a priori knowledge – fits a theoretical reason. Kant oscillated between two very different views about the a priori: on the one hand, he attributed to it a particular content, whereas on the other hand he insisted on its purely formal character. The first interpretation of the a priori was one-sidedly developed by Ørsted and led to his untenable notion of thought experiment. The other interpretation, however, can be further developed into new Kantian theories of thought experiments in the natural sciences and in philosophy.

Popper's methodological individualism and the social sciences. Popper's philosophy of social sciences poses a dilemma that arises out of the two theses of methodological individualism and situational logic. In order to find a way out of this dilemma, one must raise the question concerning the epistemological and methodological status of the `laws' of the human sciences. There are indeed `rules' from which human actions depart mostly to a negligible extent, but they remain valid or stay in effect without exception only as far as they are not re-evoked or re-emerge in the consciousness of the agents. The element of truth of methodological individualism lies in the person's capacity to revoke, in principle, the validity of the rules concerning oneself. Situational logic and methodological individualism can thus be reconciled.

Operationalism and theoretical entities. The thesis of the“theory ladenness” of observation leads to an antinomy. In order to solve this antinomy a technical operationalism is sketched, according to which theories should in principle not contain anything that cannot be reduced to technical procedures. This implies the rejection of Quine's underdeterminacy thesis and of many views about the theoretical-observational distinction, e.g. neopositivistic views, van Fraassen's view, Sneed-Stegmüller's view. Then I argue for the following theses: 1. All scientific concepts are theory laden in the sense that they allow us to anticipate possible experiences, but they have to be in principle fully observable, i.e. integrally convertible into operational-technical applications. 2. The observation/theory distinction can be maintained as a historical one: what is observable depends on the instruments that are available at any stage of the development of science. 3.In principle theoretical entities are empirically real in Hacking's sense. However, some aspects of Hacking's realism are to be criticized. Theoretical entities are to be resolved into the totality of the interrelated properties accessible to us by means of theoretical points of view embodied in scientific instruments.

The operational perspective here defended permits a reflexive-transcendental point of view that sharply distinguishes the two concepts, while, at the same time, maintaining the connection between them. On the one hand, simply imagining that the experimental apparatus, counterfactually anticipated in a thought experiment, has really been constructed is sufficient to erase any difference between thought and real experiments. On the other hand, this very ‘imagining’, this capacity of the mind to assume every real entity as a possible entity, underpins the difference in principle – a properly transcendental difference – between thought and real experiments. This difference, however, implies the intimate association between experiment and thought experiment: All thought experiments must be thought of as translatable into real ones, and all real experiments as realisations of thought ones. What thought experiments have over and above real experiments is the mere fact that they exist in a purely hypothetical sphere; what real have over and above thought experiments is the mere fact that they overstep the sphere of the possible, in the experiment’s real execution.

Marco Buzzoni Gödel, Searle, and the Computational Theory of the (Other) Mind According to Sergio Galvan, some of the arguments offered by Lucas and Penrose are somewhat obscure or even logically invalid, but he accepts their fundamental idea that a human mind does not work as a computational machine. His main point is that there is a qualitative difference between the principles of the logic of provability and those of the logic of evidence and belief. To evaluate this suggestion, I shall first compare it with Searle’s concept of “intentionality”, and then introduce a distinction between two different senses of intentionality: a reflexive-transcendental sense and a positive (that is, historical empirical or formal logical) one. In the first of these senses, the nature of human reason is such that we have no idea how a real material system – or the corresponding formal one – could instantiate it. However, although this will turn out to be an important element of truth in Searle’s and Galvan’s conception, it does not exclude the opposite truth of Turing’s functionalism: because intentionality, intuition, vision or insight – taken in their reflexive-transcendental sense – are simply invisible to the scientific eye, a man and a machine (or a robot) that is and one that is not endowed with intentionality are de facto indistinguishable from a strictly scientific point of view. For this reason, we might eventually be entitled, or even — by the practical precautionary principle – morally obliged, to attribute minds to machines.

Since the beginning of the twentieth century, prominent authors including Jean Piaget have drawn attention to Edmond Goblot’s account of mathematical thought experiments. But his contribution to today’s debate has been neglected so far. The main goal of this article is to reconstruct and discuss Goblot’s account of logical operations (the term he used for thought experiments in mathematics) and its interpretation by Piaget against the theoretical background of two open questions in today’s debate: (1) the relationship between empirical and mathematical thought experiments and (2) the question of whether mathematical thought experiments can play a justificatory function in proofs. The main corollary of this analysis is that Piaget’s interpretation is seriously flawed and insufficiently appreciative of important theses of Goblot’s account. First, Goblot can be easily defended against Piaget’s main criticism, and second, Goblot developed ideas about mathematical thought experiments that still deserve attention.

This work interprets the notion of thought experiment (TE) from the viewpoint of a functional reading of the a priori, that is, an a priori that is devoid of any particular content. It is true that Kant ascribes some content to the (synthetic) a priori, but only a functional reading of the a priori agrees with the spirit of Kant's philosophy and can be used for developing a consistent account of TEs. On the basis of this concept of the a priori, an account is developed that mediates between Brown and Norton by considering TEs from two distinct but connected points of view: transcendental and operational. On the one hand, the account is transcendental in a very usual sense of the word: TEs are the condition of the possibility of real world experiments (REs) because, without the a priori capacity of the mind to reason counterfactually, we could not devise any hypothesis and would be unable to plan the corresponding RE that should test it. This capacity underpins the distinction in principle — a properly transcendental distinction — between TEs and REs. But while there is a distinction in principle between TE and RE on the transcendental level of the a priori capacity of the mind to reason counterfactually, the exclusively func¬tional character of the a priori entails that, on the operational-methodological level, TEs —considering their empirical content and actual performance within a discipline — are and function essentially like REs.

Hermeneutic and anti-hermeneutic sides in the debate about psychoanalysis are entangled in an epistemological and methodological antinomy, here exemplified by Grünbaum's and Spence's paradigmatic views. Both contain a partial element of truth, which they assert dialectically one against the other (§§ 1 and 2). This antinomy disappears only by reconciling an operationalist approach with man's ability to suspend the effectiveness of the‘laws’ applied to him (§ 3). The hermeneutic way in which the technical-operational criterion of truth works in psychoanalysis demands that clinical and extra-clinical testing methods work synergically, through a fruitful self-correcting strategy, grounded on the very psychoanalytic object: the unconscious (§ 4).

Since the beginning of the twentieth century, prominent authors including Jean Piaget have drawn attention to Edmond Goblot’s account of mathematical thought experiments. But his contribution to today’s debate has been neglected so far. The main goal of this article is to reconstruct and discuss Goblot’s account of logical operations (the term he used for thought experiments in mathematics) and its interpretation by Piaget against the theoretical background of two open questions in today’s debate: (1) the relationship between empirical and mathematical thought experiments and (2) the question of whether mathematical thought experiments can play a justificatory function in proofs. The main corollary of this analysis is that Piaget’s interpretation is seriously flawed and insufficiently appreciative of important theses of Goblot’s account. First, Goblot can be easily defended against Piaget’s main criticism, and second, Goblot developed ideas about mathematical thought experiments that still deserve attention.

The often-emphasized tension between the singularity of the patient and technical–scientific reproducibility in medicine cannot be resolved without a discussion of the epistemological and methodological status of the human sciences. On the one hand, the rules concerning human action are analogous to the scientific laws of nature. They are de facto sufficiently stable to allow predictions and explanations similar to those of experimental sciences. From this point of view, it is only a trivial truth, but still a methodological irrelevancy, that the patient and the doctor–patient relationship represent an ontologically irreproducible reality. On the other hand, however, one can never exclude that one can fail in the application of "laws" of the human sciences to the individual patient, for such laws are by no means wholly separated from a patient's personal-hermeneutic mediation, and can at any time be revoked by becoming aware of them. This requires a synergistic collaboration of clinical and statistical methods, and shows a methodologically relevant sense in which one cannot disregard the singularity of the patient. The reason for the crucial role of the patient's singularity in medicine is every individual patient's capacity to revoke, in principle, routines and quasi-automatisms, even though the personal mediation by the patient's consciousness de facto changes them in such a small degree that predictions and explanations modeled in experimental science remain possible

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.

With reference to an already existing and relatively widespread use of the expression in question, mathematical “thought experiments” (“TEs”) involve mathematical reasoning in which visualisation plays a relatively more important role. But to ensure an unambiguous and consistent use of the term, certain conditions have to be met: (1) Contrary to what has happened so far in the literature, the distinction between logical-formal thinking and experimental-operational thinking must not be ignored; (2) The separation between the context of discovery and the context of justification is to be rejected, at least in one of the main senses in which it was defended by the logical empiricists and Popper (this excludes any position which, ascribing to mathematical TEs only a heuristic role, regards them an intermediate step to attain more traditional forms of rigour); (3) The distinction between mathematical TEs and formal proofs must be regarded as one of degree, and not as a qualitative one, although this distinction may be used in a de facto way for particular or local purposes.

Elsewhere I have tried to provide the justification of both the irreducible distinction of science and philosophy and their inevitable complementarity. Unlike empirical science, philosophy has no limit whatever as far as its possible objects are concerned. To say that there is no limit whatever to the possible objects of philosophy is to say that, strictly speaking, it has no object at all and must find its object outside itself, that is, in common sense knowledge and the natural and human sciences. Against the background of this conception, the paper argues that philosophy of science, as a critical reflection on common sense knowledge and the natural or human sciences, inherits from philosophy in general this two-faced Janus nature, which in the philosophy of science shapes the epistemological status of the discipline in an even more prominent way. To show this in detail, the paper enunciates eleven theses that derive from the intimate connection of unity and distinction that exists between philosophy of science on the one hand and the particular and specialized scientific knowledge on the other.

Despite the many turns that philosophy of technology has undergone in recent decades, the question of the nature and limits of technological determinism (TD) has been neglected, because it was considered as solved and overcome, and therefore not worth further discussion. This paper once again raises the problem of TD, by trying to save the opposing, but complementary elements of truth of the two main forms of TD that I shall call “nomological” and “normative”: (a) technology is all-pervasive and has an inexorable capacity for extending itself into every field of human life, and (b) we have a capacity to counteract and orient technology, at least in some measure. In order to reconcile these seemingly inconsistent claims, the key move for my argument is a brief analysis of the notion of scientific experiment from the perspective of the distinction between the context of discovery and the context of justification. As a result, two senses of technology are distinguished, which I shall call respectively “reflective” and “methodological.” From the point of view of this distinction, the all-pervasiveness and inexorability of technology and the in principle irreducibility of human persons to technology—which nomological and normative TD assert dialectically one against the other—can be reconciled. Among other things, this requires the rejection (in one fundamental sense) of the widely held assumption, made both by nomological and normative TD, that technology is a cultural field whose contents can be neatly separated from the rest of human culture. This thesis should be replaced by the more qualified claim of the reflective unity and the methodological multiplicity of technology.

The paper outlines a critical history of the concept of TE from a broadly Kantian viewpoint. The thread of our discussion has been Kant's position on the nature of the a priori and how each neo-Kantian theory of TEs can be understood in terms of its own position on this issue. Section 2 examines some aspects of Kant's philosophy that are related to today's debate on TEs. Section 3 is devoted to the precursors of neo-Kantian accounts of TEs, with a special emphasis on Ørsted's account. This author wavers between two positions: sometimes he claims that TEs are merely the hypothetical aspect of REs while other times he assigns to them the capacity of determining a priori some fundamental laws of natural science. The latter position recalls the "material" aspect of the Kantian a priori, a notion which was abandoned by the philosophy of science at the end of the nineteenth century. This is probably the main reason Ørsted's point of view had no real influence on the historical development of the concept of TE and why some recent Kantian or neo-Kantian accounts of TE depart from Ørsted's concept of the a priori. I, on the other hand, have defended an interpretation of the a priori as purely functional by retaining the necessary and universal character of Kant's a priori while rejecting the material a priori, since content can be given only by experience. On this view, TE and RE are complementary in a sense similar to the complementarity of form and matter in Kant: TEs without REs are empty; REs without TEs are blind. On the other hand, Yiftach Fehige has defended a relativized and contingent notion of the a priori which has been recently advocated by many authors, notably by Michael Friedman. Unlike myself, Fehige rejects the universality and necessity of Kant's a priori but retains the idea that the a priori, as a constitutive element of experience, is endowed with material content that may be made explicit by thought experimentation.