Ever since the inception of systematic economic analysis at the time of the classical economists from William Petty to David Ricardo the problem of economic growth - its sources, forms and effects - has been high on the agenda of economists.
In the real world the problem and the fact of economic growth are, of course, of much longer standing. Even in the more or less stationary economies of antiquity the possibility, if not the fact, of economic expansion lingers at the back of certain considerations.
Brick plates from Mesopotamia provide information about social productivity by means of a simple input-output calculation in terms of barley. The main question concerned the surplus product of barley that the ancient society was able to generate, that is, the excess of total output in a year with a normal harvest over the amount of input of barley as seed or as means of subsistence of labourers plus any other inputs needed in the society measured in terms of barley. From the surplus rate, that is, the ratio of surplus product to necessary input, it is obviously only a small step intellectually, but a huge step historically, to the concept of the rate of growth.