Marco Buzzoni

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.

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.

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.