Marco Buzzoni

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.

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

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.

All the most important epistemological and ontological theses of Kuhn's theory of science depend to a decisive extent on corresponding ideas of Wittgenstein's theory of meaning. The semantic and ontological assumptions that determine the main trend of Kuhn's epistemology consist, respectively, of a theory of meaning as use or application of empirical terms to nature and an ontology that conceives the real as a continuous essentially amorphous and undifferentiated, in which only language and its rules can insert order and regularity, In Kuhn's theory of science, however, beside this main trend of thought, there is another one, by far secondary, which moves towards a realistic conception of scientific theories, although it usually stops halfway, assuming the aspect of an unsustainable and unoriginal indirect realism. After highlighting the oscillations and internal difficulties not only of Kuhn's epistemology and methodology, but also of the Wittgensteinian theory of meaning, the final part of the volume outlines a realistic conception of scientific knowledge that takes as its foundation the intrinsically cognitive nature of instrumental operations and tries to provide a satisfactory response to Kuhn's challenge and, in particular, to his thesis of incommensurability. From this point of view, the use and reference of scientific terms or theories are constitutive and inseparable moments of their meaning, and refer to an internally structured relational reality.

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.