Purpose: The purpose of this paper is to trace the development of economic theory to the point where "economic rationalism" is a commonly used term. Design/methodology/approach: The paper draws on earlier research and published works examining: the history of economics; economic rationalism; and the different influences in comprising basic economic concepts. Findings: The analysis of writing indicates that rationalism has been a focus of discussion in economic writing since Classical times, through to the "rational" influence in economic policy making from neoclassical economic writing. But, the specific term "economic rationalism" gained wider usage after Pusey's book. From that time, the term was used outside academia as a disparaging means to criticise economic theorists and policy makers. Research limitations/implications: The research is limited by the ability to examine all the literature in the field in greater depth. However, this has been ameliorated by examining a sufficient sample of literature relevant to the concept of rationality in economic theory and policy. Practical implications: This paper provides a useful critique - from the classics to the modern era - of the contribution made to economic theory and practice. It provides managers with a comprehensive historical overview. Originality/value: This paper fulfils an identified need and gives support to executives and managers who have doubts about theological justification for some values and accountability procedures being employed in policymaking.