Evandro Agazzi has defended an ideal of medicine in which the hermeneutical-existential and the scientific-objective dimensions can cooperate to understand the human experience of malady. The paper supports this account by justifying such a cooperation on epistemological and methodological grounds intrinsically related to the peculiar status of medicine as a human science. The peculiarity of the “laws” of medicine as a human science demands a synergistic, reciprocal, and continuous interaction of clinical-personal and extraclinical-biomedical testing. The resulting spiral movement is one of the most general epistemological and methodological conditions for the possibility of realizing, at least in part and in an ongoing process, an ideal of medicine in which objective, biomedical and extraclinical knowledge, on the one hand, and the personal and clinical knowledge, on the other, can work together to reliably promote the goal of health in its two main meanings of the term, the analytic-naturalistic and the phenomenological-existential.

Kant did not distinguish between thought experiments (TEs) and real world experiments, nor did he use the German term “Gedankenexperiment”. But many aspects of Kant’s thought are related to the concept of TE, and especially “the experiments of reason” ( Experimente der Vernunft ), which are the distinguishing feature of transcendental arguments in philosophy as compared with the mathematical and empirical sciences. The first part of this paper reconstructs the Kantian concept of “experiments of reason”. In the second part, a functional account of Kant’s a priori is defended and contrasted with Ørsted’s first Kantian interpretation of TEs. The entirely functional view of the a priori leads to an account of TEs in philosophy which is characterized by the following four features: 1) transcendental arguments, interpreted as philosophical TEs, are exemplifications of counterfactual reasoning that are expressions of the unlimited criticism typical of philosophy; 2) as far as their content is concerned, they depend entirely on information from ‘outside’, i.e. from common life experience and the empirical sciences, and it is this content that, albeit with respect to the conditions of possibility, grounds the criterion of their internal consistency; 3) apart from the reversal of the direction of enquiry, there is no difference in principle between the special methods of reasoning adopted in scientific and philosophical TEs (any such difference could only be based on a material conception of the a priori); 4) both philosophy and philosophical TEs have in the last analysis only a critical or negative task, that of denouncing all attempts to reduce the human person to categories or concepts derived, explicitly or implicitly, from empirical reality (whether natural or cultural).

The paper attempts to clarify a fundamental similarity and some relevant differences between empirical-scientific and fictional thought experiments. For this purpose, the second section of the paper provides a brief outline of a quasi-Kantian account of thought experiments (TE) in the empirical sciences from the viewpoint of a radically functional, strictly not material, a priori. On the basis of this account, a fundamental similarity and two main differences between empirical-scientific and narrative thought experiments are brought to the fore: the counterfactual construction of idealised scenarios is a fundamental characteristic that is shared by scientific and fictional thought experiments (and, more generally, by science and art). The differences depend on the different intentionalities to which this construction is subordinated. Fictional TEs, instead of resolving the dimension of counterfactuality in real empirical facts or processes, use it to transpose certain cultural contents (thoughts, feelings, possible courses of action, etc.) into a dimension outside any particular space and time, which are able to produce a symbolic shelter that protects us from the particular adverse events of concrete life. This, on the one hand, generates in us the feeling of pleasure or enjoyment that tradition has so often linked to artistic enjoyment and, on the other, urges us, implicitly or explicitly, to re-enact those contents in the first person and to take an evaluative stance towards them.

Hempel’s account of thought experiments has been discussed only by a very few authors and, for the most part, with rather cursory remarks. Its importance, however, is not only historical, but also systematic theoretical, because it involves the distinction between discovery and justification, a main pillar of neopositivistic philosophy of science. Hempel raised the question whether thought experiments constitute a methodological component of scientific research or, on the contrary, are merely a heuristic-psychological device for obtaining and/or transmitting new ideas. While conceding a few exceptions in the natural sciences, he argued that thought experiments always have a heuristic character in the social sciences. There is however a fundamental tension in Hempel’s conception of thought experiments, between the thesis of methodological monism and the neopositivistic dichotomy discovery/justification. On the one hand, on the basis of the unity of scientific method, Hempel admits a difference only in degree between the natural and the human sciences, but on the other hand, he draws a principled distinction between thought experiments of the human sciences (which have only a greater or lesser heuristic value) and those of the natural sciences (which may have also a cognitive-justificatory value). If one assumes the unity of method in the minimal sense in which no scientific knowledge can renounce intersubjective controllability, this tension can be removed either by rejecting the discovery/justification dichotomy or by interpreting it differently. Here, following the second path, two senses of the dichotomy are distinguished, one of which must be accepted, while the other rejected. This removes the internal tension in Hempel’s conception of thought experiments and suggests the thesis that any plausible thought experiment, both in the natural and the human sciences, must already contain some justification, implicit or explicit, of the theoretical hypotheses that they formulate.

Bridgman’s operationalism incurred serious difficulties, and this fact induced many authors to dismiss operationalism per se. Developed beginning in the late 1960s, Agazzi’s operationalism escaped these difficulties from the beginning, but the persistence in it of a traditional primacy attributed to theory over experiment led him to pose an opposition between science and technique that was inconsistent with the general operationalist framework of his philosophy of science. Later, Agazzi sought to make his operationalism more coherent by moving toward a closer relationship between science and technology, that is, toward an intermediate solution which sees them as interacting with one another. However, in order to coherently defend an intermediate solution, it is not enough to find a certain set of properties that would be peculiar to science but not to technique, or vice versa. Rather, it is necessary to specify two distinct (but also complementary) points of view, from which science and technique can appear, at the same time but without contradiction, both as conceptually distinct and as indistinguishable as historical-empirical realities: in one sense, science is irreducible from technology, but in the other sense, they coincide completely.

Method and creativity seem to be, at least at first sight, opposing concepts. The problem has recently been taken up again in the discussion around serendipity, i.e. the phenomenon in which a fortuitous and unexpected experience turns out to be an essential ingredient of a discovery or invention. How can chance be essential to research conducted methodically? The two essential ingredients of chance and method give rise to what, in the discussion on serendipity, has been called the paradox of control: the concept in question invokes chance and luck and at the same time proposes itself as a kind of method, capable of leading to ever new discoveries or inventions. To solve this paradox, it is necessary to critically rethink both the acceptance of the logical empiricist distinction between discovery and justification and its more recent rejection within the epistemological tradition. I propose a distinction between two senses – reflexive-transcendental and genetic-methodological – of the discovery/justification dichotomy that may dissolve the paradoxical nature of serendipity. From this point of view, an empirical discovery always moves from accidental and contingent conditions (which as such are not only unplanned but also independent of us) to the formulation of a new question to which those same conditions, now transformed into essential constituents of a thought experiment, provide an intersubjectively reproducible and testable answer.

The New Experimentalism, given its opposition between experimental practices and fundamental theories, had to address the problem of the relationship between the particularity of the former and the generality of the latter. Other authors (from Charles A. Baylis and Nelson Goodman to Catherine Elgin) used the concept of exemplification to clarify the relationship between particular and universal/general concepts or laws. But one may ask whether, while hinting at a point of view that can illuminate new aspects of the problem, they have not ultimately left the problem itself unresolved. This article, on the basis of considerations developed elsewhere and following a suggestion found in Aristotle, proposes to link the concept of exemplification to the problem of induction and abduction, both understood here as a multiplicity of methodical procedures aimed at establishing a cognitive relationship between the reproducibility of scientific concepts or laws and the concreteness, locality, and situated character of experimental practices. A necessary prerequisite for the solution of the problem raised by this relationship is the distinction between two senses – one reflexive-transcendental, the other genetic-methodological – of the discovery/justification pair of concepts. This will shed light, at the same time, on the long-standing problem of induction and on the problem of the relationship between the universality of scientific laws and the always local and situated character of experimental practices. The last part of the article shows how these conclusions also apply to thought experiments, briefly discussing John Norton’s account.

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.

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 (i.e., a science that studies humans); 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.

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.

In a recent paper, Sharpe and Greco (2019) argue that some clinical conditions, such as chronic fatigue syndrome (sometimes called myalgic encephalomyelitis), should be treated by altering the patient's experience and response to symptoms without necessarily searching for an underlying cause. As a result, we should allow for the existence of 'illnesses without (underlying) diseases'. Wilshire and Ward (2019) reply that this possibility requires unwarranted causal assumptions about the psychosocial origins of conditions not predicted by a disease model. In so doing, it is argued that Sharpe and Greco introduce epistemological and methodological problems with serious medical consequences, for example, patients feel guilt for seeking treatment for illnesses that only exist 'all in the mind', and medical researchers are discouraged from looking for more effective treatments of such conditions. We propose a view that integrates the insights of both papers. We abandon both the strict distinction between disease and illness and the naïve unidirectional account of causality that accompanies it. This, we claim, is a step towards overcoming the current harmful tendencies to conceptually separate (1) Symptom management and disease-modifying treatments. (2) Rehabilitative-palliative care and 'causal' curing. (3) Most importantly, biomedicine and clinical medicine, where the latter is currently at risk of losing its status as scientific.

Elsewhere I have tried to provide the justification of both the irreducible (transcendental) distinction of science and philosophy and their inevitable (naturalistic) 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 conventional interpretation that Duhem condemned outright any type of thought experiment in Mach's sense should be, at least in large part, rejected. There are some interesting remarks made by Mach and Duhem that suggest a very different reading. In this paper I shall take up and develop these remarks, which lead to the conjecture that Duhem's criticism was not intended to be a complete rejection of thought experiments but a completion and supplement of Mach's theory. Duhem, while retaining the core idea of Mach's theory - according to which thought experiments cannot break free from the ultimate authority of real world experiments -, laid particular emphasis on the perils of thought experiment, which Mach had overlooked or, at least, underestimated.

Starting from Fehige's and Polkinghorne's analyses of the analogies between theological and scientific thought experiments (TEs), the main aim of this paper is to clarify the distinctive character of theological TEs. For this purpose, we shall compare theological TEs with empirical and, although only in passing, with narrative TEs. In order to facilitate the comparison between scientific and theological TEs, the first part of the paper provides a brief outline of an account regarding TEs in the empirical sciences from the viewpoint of a functional, not material, a priori, which is in line with, if not the full letter, the spirit of Kant's a priori. On the basis of this view, we shall investigate the most important difference (which is the source of many others) between theological and empirical TEs. In spite of the many similarities, the most important difference between empirical and theological TEs lies in the fact that theological TEs consider both empirical-descriptive and moral-normative contents from the point of view of a search for an absolute meaning beyond all relative and finite meanings. If we-developing a suggestion by Ernst Troeltsch-interpret this claim from the point of view of a purely functional religious a priori, we may conclude that theological TEs, which express a search for an absolute meaning, do not possess a priori contents, not even moral.