A time will come when science will transform [our bodies] by means which we cannot conjecture... And then, the earth being small, mankind will migrate into space, and will cross the airless Saharas which separate planet from planet, and sun from sun. The earth will become a Holy Land which will be visited by pilgrims from all quarters of the universe.

All the events which occur upon the earth result from Law: even those actions which are entirely dependent on the caprices of the memory, or the impulse of the passions, are shown by statistics to be, when taken in the gross, entirely independent of the human will. As a single atom, man is an enigma; as a whole, he is a mathematical problem. As an individual, he is a free agent; as a species, the offspring of necessity.

Doubt is the offspring of knowledge: the savage never doubts at all.

If we look into ourselves we discover propensities which declare that our intellects have arisen from a lower form; could our minds be made visible we should find them tailed.

It is a sure criterion of the civilisation of ancient Egypt that the soldiers did not carry arms except on duty, and that the private citizens did not carry them at all.

Man … begins life as an ambiguous speck of matter which can in no way be distinguished from the original form of the lowest animal or plant. He next becomes a cell; his life is precisely that of the animalcule. Cells cluster round this primordial cell, and the man is so far advanced that he might be mistaken for an undeveloped oyster; he grows still more, and it is clear that he might even be a fish; he then passes into a stage which is common to all quadrupeds, and next assumes a form which can only belong to quadrupeds of the higher type. At last the hour of birth approaches; coiled within the dark womb he sits, the image of an ape; a caricature of the man that is to be. He is born, and for some time he walks only on all fours; he utters only inarticulate sounds; and even in his boyhood his fondness for climbing trees would seem to be a relic of the old arboreal life.

Men prefer to believe that they are degenerated angels, rather than elevated apes.

The essence of religion is inertia; the essence of science is change. It is the function of the one to preserve, it is the function of the other to improve. If, as in Egypt, they are firmly chained together, either science will advance, in which case the religion will be altered, or the religion will preserve its purity, and science will congeal.

The philosophic spirit of inquiry may be traced to brute curiosity, and that to the habit of examining all things in search of food. Artistic genius is an expansion of monkey imitativeness.

The spirit of science arises from the habit of seeking food; the spirit of art arises from the habit of imitation, by which the young animal first learns to feed; the spirit of music arises from primeval speech, by means of which males and females are attracted to each other.

Winwood Reade … remarks that while a man is an insoluble puzzle, in the aggregate he becomes a mathematical certainty. You can, for example, never foretell what any one man will do, but you can say with precision what an average number will be up to. Individuals vary, but percentages remain constant. So says the statistician.