The 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.

A writer may tell me that he thinks man will ultimately become an ostrich. I cannot properly contradict him.

The passion between the sexes has appeared in every age to be so nearly the same, that it may always be considered, in algebraic language as a given quantity.

[P]opulation, when unchecked, goes on doubling itself every twenty-five years, or increases in a geometrical ratio. ... [T]he means of subsistence, under circumstances the most favorable to human industry, could not possibly be made to increase faster than in an arithmetical ratio.

Had population and food increased in the same ratio, it is probable that man might never have emerged from the savage state.

It is not the most pleasant employment to spend eight hours a day in a counting house.

No limits whatever are placed to the productions of the earth; they may increase forever.