If problems of historical study are to be chosen on the basis of their importance in affecting the course of human affairs through time, no phase of life in Western culture during the century and a half after 1800 is more worthy of study than that of economic development. During these one hundred and fifty years there was an increment of total production within western Europe of an estimated 1,500 per cent and an increase of output per capita of some 500 per cent. At no time in history had an equal advance been made at such a rapid pace.