The Historical Demography of the Scientific Community,1450-1900

About the middle of the fifteenth century, there was an almost abrupt onset of sustained growth in the number of persons we can call `scientists' - in marked contrast to the absence of any overall growth in the late Middle Ages. Thereafter, the scientific community grew through the centuries at a roughly exponential rate, with a doubling time of about fifty years (a much lower rate than has previously been reported). At the beginning of the modern period, roughly half of all scientists were Italians, but subsequently the proportion declined as scientific activity expanded in other countries, especially France, Britain and Germany. Each of these countries exhibits its own peculiar pattern of growth, as do the smaller countries which made sizeable contributions. In the two future giants, Russia and the United States, a quite different pattern is evident. The various fields of science also have peculiarities in the numbers of their practitioners.