Heisenberg, in constructing quantum mechanics, explicitly followed certain principles exemplified, as he believed, in Einstein's construction of the special theory of relativity which for him was the paradigm for radical theoretic change in physics. These were the principles of scientific realism, stability of background knowledge, E-observability, contextual re-interpretation, pragmatic continuity, model continuity, simplicity. Fifty years later, in retrospect, Heisenberg added the following two: a principle of non-proliferation of competing theories - scientific revolutions are not a legitimate goal of physics - (...) and a principle of tenacity - existing theories are to be conserved as far as possible. The conservative as well as the revolutionary potential of these principles is then discussed. A more penetrating philosophical criticism of these principles is postponed. (shrink)

Summary The present paper constitutes an elaboration of a previous work by one of us which, among other things, proposed some modifications of Popper's tetradic schema. Here, in the first part, we consider critically and develop further these modifications and elaborate on methods which prove more satisfactory for the mapping of the problem solving processes in Physics. We also find the opportunity to make some comments on Physics and on its relation to Mathematics. In the second part, there is an (...) attempt to test the above ideas on the genesis and development of the Special Relativity Theory. In doing this, we concentrate mainly on Einstein's 1905 paper and try to explicitate its relation with the situation Physics found itself in that period as well as to clarify the epistemological status of Einstein's two postulates. (shrink)