The germs of existence contained in this spot of earth, with ample food, and ample room to expand in, would fill millions of worlds in the course of a few thousand years.

Nature herself in times of great poverty or bad climatic conditions, as well as poor harvest, intervenes to restrict the increase of population of certain countries or races; this, to be sure, by a method as wise as it is ruthless.

It does not, however, seem impossible that by an attention to breed, a certain degree of improvement, similar to that among animals, might take place among men. Whether intellect could be communicated may be a matter of doubt: but size, strength, beauty, complexion, and perhaps even longevity are in a degree transmissible... As the human race could not be improved in this way, without condemning all the bad specimens to celibacy, it is not probable, that an attention to breed should ever become general.

The constant effort towards population, which is found even in the most vicious societies, increases the number of people before the means of subsistence are increased.

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.

Population, when unchecked, increases in a geometrical ratio. Subsistence increases only in an arithmetical ratio. A slight acquaintance with numbers will shew the immensity of the first power in comparison of the second.

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.