Abstract: An initial introduction to the semantic approach to science, this chapter provides a view of scientific theories in terms of classes of models and their relation to the phenomena. The main tasks of philosophy of science can be carried out within the framework of this approach without drawing on any metaphysical notions or principles. A specific problem examined here (which introduces a change from the author's previous book The Scientific Image) is how to characterize acceptance of a probabilistic theory. Probabilities in certain contemporary physical theories are irreducible and thus purport to stand for physical aspects of nature. But on and empiricist view, acceptance of such a theory does not need to involve belief in the reality of such objective chances. This problem is solved in an extension of the probabilist epistemology of the previous chapter.

Keywords: acceptance, epistemology, models, probability, semantic approach, theories,