“Tolerably early in life I discovered that one of the unpardonable sins in the eyes of most people is for a man to go about unlabeled. The world regards such a person as the police do an unmuzzled dog.”

“When in 1863 Thomas Huxley coined the phrase 'Man's Place in Nature,' it was to name a short collection of his essays applying to man Darwin's theory of evolution. The Origin of Species had been published only four years before, and the thesis that man was literally a part of nature, rather than an earthy vessel charged with some sublimer stuff, was so novel and so offensive to current metaphysics that it needed the most vigorous defense. Half the civilized world was rudely shocked, the other half skeptically amused.Nearly a century has passed since the Origin shattered the complacency of the Victorian world and initiated what may be called the Darwinian revolution, an upheaval of man's ideas comparable to and probably exceeding in significance the revolution that issued from Copernicus's demonstration that the earth moves around the sun. The theory of evolution was but one of many factors contributing to the destruction of the ancient beliefs; it only toppled over what had already been weakened by centuries of decay, rendered suspect by the assaults of many intellectual disciplines; but it marked the beginning of the end of the era of faith.”

“The only medicine for suffering, crime, and all other woes of mankind, is wisdom. Teach a man to read and write, and you have put into his hands the great keys of the wisdom box. But it is quite another thing to open the box.”

“In science, as in art, and, as I believe, in every other sphere of human activity, there may be wisdom in a multitude of counsellors, but it is only in one or two of them.”

“It is not who is right, but what is right, that is of importance.”

“Economy does not lie in sparing money, but in spending it wisely.”

“It is one of the most saddening things in life that, try as we may, we can never be certain of making people happy, whereas we can almost always be certain of making them unhappy.”

“The scientific imagination always restrains itself within the limits of probability.”

“Learn what is true in order to do what is right.”

“The improver of natural knowledge absolutely refuses to acknowledge authority, as such. For him, skepticism is the highest of duties; blind faith the one unpardonable sin.”

“Every great advance in natural knowledge has involved the absolute rejection of authority.”