which opened the way to new kinds of economic reasoning. But still it was not enough: the nineteenth-century model of economic man may have been ever-calculating, but he was not all-knowing, and his inherent uncertainty (which forced him to act upon opinion rather than knowledge) barred the way to complete mathematical modeling. Hence in the 1920s, Chicago-school economist Frank Knight decided to endow economic man with two godlike traits—perfect knowledge and perfect foresight—enabling him to compare all goods and prices across all time.
