A “free play with concepts”: Philosophy and epistemology in Albert Einstein's scientific thought

Closely related to the development of his properly scientific activity, the philosophical and epistemological structure of Albert Einstein’s scientific work is also marked by a strong underlying unity, which appears in similar forms from the first papers at the turn of the twentieth century to the attempts to construct unified field theories, which unsuccessfully occupied him in the last part of his career. This paper presents some of the main traits that characterised Einstein’s philosophical and epistemological thought: Ernst Mach’s influence and Einstein’s ambivalence towards Mach’s theoretical legacy, the philosophical problem offered by the complex relationship between theory and experience, and the specific image of scientific rationality to which Einstein devoted some of his deepest explicitly philosophical essays.