Introduction

Abstract

The concept of uncertainty has much evolved since F. Knight wrote his seminal book on Risk, Uncertainty and Profit. Economists have generally reduced the concept to the idea that no probability was available, as opposed to the case of risk. What Knight meant might have been sensibly different: Was not uncertainty the case where probability could not be defined with precision, where there was no consensus measure? In the 1920s, such an imprecision was often sufficient to make any corresponding amounts at stake uninsurable.