Page:Progress and poverty - an inquiry into the cause of industrial depressions, and of increase of want with increase of wealth - the remedy (IA progresspovertyi00georiala).pdf/109

Chap. I. than corrected. Indeed, it is certain that without Smith there would have been no Malthus; that is, unless Smith had laid the foundation, Malthus could not have raised the superstructure."

The famous doctrine which ever since its enunciation has so powerfully influenced thought, not alone in the province of political economy, but in regions of even higher speculation, was formulated by Malthus in the proposition that (as shown by the growth of the North American colonies) the natural tendency of population is to double itself at least every twenty-five years, thus increasing in a geometrical ratio, while the subsistence that can be obtained from land "under circumstances the most favorable to human industry could not possibly be made to increase faster than in an arithmetical ratio, or by an addition every twenty-five years of a quantity equal to what it at present produces."

"The necessary effects of these two different rates of increase, when brought together," Mr. Malthus naively goes on to say, "will be very striking." And thus (Chap. I) he brings them together:

Such a result is of course prevented by the physical fact that no more people can exist than can find subsistence, and hence Malthus' conclusion is, that this tendency of population to indefinite increase must be held back either by moral restraint upon the reproductive faculty, or by the