Might it not be more accurate, chronologically, to trace the origins of 'scientism' in American economics to the (old) Institutionalists, in particular to Veblen? One thing is certain, Wesley Mitchell and the NBER antedated Tingergen's pioneering attempts to build quantitative macro-models. It may also be plausible to associate scientism with 'market socialism', as exemplified in the work of Lange, Lerner and Taylor. See for example F. M. Turner's presidential address to the AEA of 1929. At least since the beginning of the 20th C there was a growing feeling, among Anglophone social scientists on the political left, that human social phenomena could be analysed as determinate rational processes, and that the ills of human societies (as diagnosed by the political left) could be prescribed for in a truly scientific manner. Not until Mises and Hayek, I think, was this taken-for-granted assumption seriously questioned among British and American economists. It was certainly alive and well in the Cambridge of the 1950s, where the very few dissenters (Bauer, Denison) were ignored and marginalised. In backward, intellectually isolated Australia it survived as late as 1964, where Trevor Swan once said to me, 'of course I'm a socialist'. But if we are really interested in the history of economic thought, we might well discover economics scientism in Quesnai and the other 'Physiocrats'. Anthony Waterman