On the other hand, the psychology of analogical thinking and cognitive habits may also inform our understanding of the concept of a paradigm. Kuhn himself tells us that “The paradigm as shared example is the central element of what I now take to be the most novel and least understood aspect of [The Structure of Scientific Revolutions]” (1970a, 187). Kuhn, however, failed to develop the paradigm concept in his later work beyond an early application of its semantic aspects to the explanation of incommensurability. Nonetheless, other philosophers, principally Howard Margolis (1987, 1993) have developed the idea that habits of mind formed by training with paradigms-as-exemplars are an important component in understanding the nature of scientific development.  As explained by Nickles (2003b) and Bird (2005), this is borne out by recent work by psychologists on model-based and analogical thinking.