 Developing Thomas Kuhn’s notion of a “paradigm” (1970) and some hints from Popper, Lakatos also presented a view of the global theory structure of whole theoretical enterprises, which he called “scientific research programmes.” Lakatos emphasized that there is a “hard core” of basic theoretical propositions that define a research programme and that are not to be questioned within the research programme. In addition members of a research programme accept a common body of heuristics that guide them in the articulation and modification of specific theories. These views have also been attractive to economic methodologists, since theory development in economics is sharply constrained and since economics appears at first glance to have a “hard core.” The fact that economists do not give up basic theoretical postulates that appear to be false might be explained and justified by regarding them as part of the “hard core” of the “neoclassical research programme”.