My own feeling of concern arises from seeing how much moral injury and suffering is created by the superstitions of the Christian mythology.

It is my deliberate opinion that the one essential requisite of human welfare in all ways is scientific knowledge of human nature.

His subject is the "Origin of Species," & not the origin of Organization; & it seems a needless mischief to have opened the latter speculation at all.

If a test of civilization be sought, none can be so sure as the condition of that half of society over which the other half has power.

I am sure that no traveler seeing things through author spectacles can see them as they are.

I want to be a free rover on the breezy common of the universe.

Of tobacco and its consequences, I will say nothing but that the practice is at too bad a pass to leave hope that anything that could be said in books would work a cure. If the floors of boarding-houses, and the decks of steam-boats, and the carpets of the Capitol, do not sicken the Americans into a reform; if the warnings of physicians are of no avail, what remains to be said? I dismiss the nauseous subject.