The aim of this paper is to characterize the various structuralist reduction concepts as structure-preserving maps in a succinct and unifying way. To begin with, some important intuitive adequacy conditions are discussed that a good (structuralist) reduction concept should satisfy. Having reconstructed these intuitive conditions in the structuralist framework, it turns out that they divide into two mutually incompatible sets of requirements. Accordingly there exist (at least) two essentially different types of structuralist reduction concepts: the first type stresses the existence (...) of a deductive or inferential link between the reducing and the reduced theory; the second type emphasizes the greater explanatory power the reducing theory should have in comparison with the reduced theory. The problem of the incompatibility of equally plausible reduction concepts is treated in the last section and a proposal is made for its solution consisting in the definition of a multiple synthetizing reduction relation. (shrink)

An exact formulation of the frequency interpretation of probability is proposed on the basis of G. Ludwig's concept of physical theories. Starting from a short outline of this concept, a formal definition of weak approximate reduction is developed, which covers the reduction of probability to frequency as a special case.

A comprehensive model for describing various forms of developments in science is defined in precise, set-theoretic terms, and in the spirit of the structuralist approach in the philosophy of science. The model emends previous accounts in centering on single systems in a homogenous way, eliminating notions which essentially refer to sets of systems. This is achieved by eliminating the distinction between theoretical and non-theoretical terms as a primitive, and by introducing the notion of intended links. The force of the model (...) is demonstrated by formally incorporating many of the important, precise meta-theoretic concepts occurring in the literature. (shrink)

My thesis is that some methodological ideas of the Pozna school, i.e., the principles of idealization and concretization (factualization), and the correspondence principle can be represented rather successfully using the relations of theoretization and specialization of revised structuralism.Let n(i), t(j)> (i=1,...m, j=1,...k) denote the conceptual apparatus of a theory T, and a class M={} (i=1,...m, j=1,...k) the models of T. The n-components refer to the values of dependent variables and t-components to the values of independent variables of the theory. The (...) n- and t-components in turn represent appropriate concepts. Consider T * as a conceptual enrichment of T with concepts n(i *), t(j *)> (ii * or jj *) and models M *={D *, n(i *), t(j *)>}. If the classes M and M * are suitably related, then the situation illustrates both the case of the theoretization-relation of (revised) structuralism and of the factualization-principle of the Pozna school. (shrink)

Patrick Suppes'' set-theoretical approach to the analysis of theories, and Joseph D. Sneed''s metatheory are briefly outlined. The notions of observation, illusion and hallucination are reconstructed according to these approaches. It is argued that the terms perception and truth are theoretical with respect to observation but nontheoretical with respect to illusion and hallucination. Hallucination is construed as a special kind of illusion.

Patrick Suppes' set-theoretical approach to the analysis of theories, and Joseph D. Sneed's metatheory are briefly outlined. The notions of observation, illusion and hallucination are reconstructed according to these approaches. It is argued that the terms ‘perception’ and ‘truth’ are theoretical with respect to observation but nontheoretical with respect to illusion and hallucination. Hallucination is construed as a special kind of illusion.

We revive the idea that a deductive-nomological explanation of a scientific theory by its successor may be defensible, even in those common and troublesome cases where the theories concerned are mutually incompatible; and limiting, approximating and counterfactual assumptions may be required in order to define a logical relation between them. Our solution is based on a general characterization of limiting relations between physical theories using the method of nonstandard analysis.