No state has hitherto existed (at least that we have any account of) ... that no check whatever has existed to early marriages, among the lower classes, from a fear of not providing well for their families, or among the higher classes, from a fear of lowering their condition in life.
Thomas MalthusPopulation, when unchecked, goes on doubling itself every 25 years or increases in a geometrical ratio.
Thomas MalthusWhere there are few people, and a great quantity of fertile land, the power of the earth to afford a yearly increase of food may be compared to a great reservoir of water, supplied by a moderate stream. The faster population increases, the more help will be got to draw off the water, and consequently an increasing quantity will be taken every year. But the sooner, undoubtedly, will the reservoir be exhausted, and the streams only remain.
Thomas MalthusThe main peculiarity which distinguishes man from other animals is the means of his support - the power which he possesses of very greatly increasing these means.
Thomas Malthus