Assuming that in order to foster Organizational Learning (OL), one has to supply organizations with occasions for learning, this paper undertakes a theoretical analysis of OL-causes. Assumptions contained in OL-concepts are classified and interpreted within the light of learning theory and cognition theory. Drawing upon constructivist theories of cognition, the paper shows that all assumptions can be formulated as differences which make differences'. In addition, a constructivist interpretation discloses that differences result from drawing distinctions'. Based upon these insights, strategies to improve OL are suggested and related to findings of current management research