Principal idea of capitalism: the people only work because and so long as they are poor

This is an excerpt from "The Protestant Ethic and the Spirit of Capitalism"  by Max Weber

Another obvious possibility, to return to our example, since the appeal to the acquisitive instinct through higher wage-rates failed, would have been to try the opposite policy, to force the worker by reduction of his wage-rates to work harder to earn the same amount than he did before. Low wages and high profits seem even to-day to a superficial observer to stand in correlation; everything which is paid out in wages seems to involve a corresponding reduction of profits. That road capitalism has taken again and again since its beginning. For centuries it was an article of faith, that low wages were productive, i.e. that they increased the material results of labour so that, as Pieter de la Cour, on this point, as we shall see, quite in the spirit of the old Calvinism, said long ago, the people only work because and so long as they are poor