The immediate cause of the increase of population is the excess of the births above deaths; and the rate of increase, or the period of doubling, depends upon the proportion which the excess of the births above the deaths bears to the population.

The finest minds seem to be formed rather by efforts at original thinking, by endeavours to form new combinations, and to discover new truths, than by passively receiving the impressions of other men's ideas.

The great and unlooked for discoveries that have taken place of late years have all concurred to lead many men into the opinion that we were touching on a period big with the most important changes.

With regard to the duration of human life, there does not appear to have existed from the earliest ages of the world to the present moment the smallest permanent symptom or indication of increasing prolongation.

A feather will weigh down a scale when there is nothing in the opposite one.

Hard as it may appear in individual instances , dependent poverty ought to be held disgraceful.

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