We have seen salutary advances in the historico-theoretical study of Institutional Economics in the last decade. The focal point seems to have shifted from Veblen to Commons, reflecting the florescence of so-called New Institutional Economics that puts stress on the spontaneous growth of social order guided by the free will of individual. It is, indeed, a fact that Commons's institutionalism that emphasizes the role of volitional will and artificial selection has close links with New Institutional Economics (Rutherford, 1994). Ramstad (1990; 1995) construes the concept of “working rules” as the connecting and binding element in the multiplicative theory of Commons. Biddle (1990) alleges that Commons developed an evolutionary theory of the results of intended conduct, though he did not overlook the unintended results of conduct. These two interpretations are persuasive, but certain inevitable questions might come to mind: Are the concepts of working rules too vague and elastic to use for objective analysis?: Is it possible to maintain logical consistency between the logic of the outcome of the intended conduct and the logic of unintended outcome?<br>A new interpretation of Veblen's theory of evolution is presented by Taka (1991; 1996). Although the instinct of workmanship (idle curiosity) leads autonomously to the development of technology, the prevailing institutions of the society, that is, the norms of conduct or the standards of esteem, are always the consequences of emulation. The order of development or expansion is as follows: instinct of workmanship→exploit (pro wess)→trophy→private property→conspicuous consumption and leisure. Since these norms of conduct have been historically accumulated in strata like the twisted ladder of a gene, people forced to adapt to the new circumstances often choose to retard or retrogress to the inherited and accustomed ways of thinking, that is, old fashioned customs and institutions. Veblen's theory of evolution consists of evolution and retrogression.<br>Generally speaking, in order to reinterpret critical or heterodox economic thoughts such as Institutionalism, we must also reinterpret American orthodox, neo-classical thought at the same time. Mehring (1997), Shute (1997) and Yonay (1998) make, in this sense, a valuable contribution to the study of Institutional Economics.