How is scientific knowledge of social facts and relations possible? How can the biases of a scientist's own personality and of his time and his local and class milieu be prevented from influencing the direction of his search for the facts and his inferences from them?
How can he liberate his thinking from the powerful tradition of the living and the dead masters of his science? More specifically, how can he free himself from normative and teleological notions, inherited from previous generations and founded upon the metaphysical moral philosophies of natural law and utilitarianism from which all our social and economic theories have branched off? Do not these doctrinal elements still set the stage for our inquiries, determine the direction of our research and prejudice the conclusions from it? How can the social sciences overcome their irrational impact and become entirely relativist with respect to values, as a systematic search for truth should be? These, as I recall, were the questions with which I found myself confronted in my earliest endeavours to prepare myself to become an economist.
When, as newly appointed docent at the University of Stockholm, I had to deliver a series of lectures, I chose for the Spring term of 1928 the topic: "The Concepts 'Value' and 'Utility' in Economic Theory." My main interest at that time was negative: to demonstrate that certain practices of reasoning common in economics were logically defective. In spite of general pronouncements by almost all leading economists, from N. Senior and J. S. Mill onwards, that the science of economics should be concerned only with what is and not what ought to be, economic theory had preserved elaborate structures of normative speculation built upon the