Perhaps no order of mammals presents us with so extraordinary a series of gradations as this [step by step, from humans to apes to monkeys to lemurs] - leading us insensibly from the crown and summit of the animal creation down to creatures, from which there is but a step, as it seems, to the lowest, smallest, and least intelligent of the placental Mammalia. It is as if nature herself had forseen the arrogance of man, and with Roman severity had provided that his intellect, by its very triumphs, should call into prominence the slaves, admonishing the conqueror that he is but dust.

The results of political changes are hardly ever those which their friends hope or their foes fear.

Science is simply common sense at its best, that is, rigidly accurate in observation, and merciless to fallacy in logic.

When I reached intellectual maturity and began to ask myself whether I was an atheist, a theist, or a pantheist; a materialist, or an idealist; a Christian, or a freethinker; I found that the more I learned and reflected, the less ready was the answer; until, at last, I came to the conclusion that I had neither art nor part with any of these denominations, except the last.

The only freedom I care about is the freedom to do right; the freedom to do wrong I am ready to part with on the cheapest terms to anyone who will take it of me

If the perpetual oscillation of nations between anarchy and despotism is to be replaced by the steady march of self-restraining freedom, it will be because men will gradually bring themselves to deal with political, as they now deal with scientific questions.

The dogma of the infallibility of the Bible is no more self-evident than is that of the infallibility of the popes.