Grete Hermann's 1935 article "Die naturphilosophischen Grundlagen der Quantenmechanik" remains not only an important historical contribution to the philosophy of physics, but until today her viewpoint concerning the issue of causality in quantum theory raises questions. Her argumentation is strongly influenced by an article by Carl Friedrich von Weizs?cker from 1931, in which he analyses the "Heisenberg microscope". My aim is to briefly review the main ideas of this article and the way how it may have shaped the thinking of Grete Hermann.