I have never been able to understand why pigeon-shooting at Hurlingham should be refined and polite, while a rat-killing match in Whitechapel is low.

I took thought, and invented what I conceived to be the appropriate title of 'agnostic'.

The world is neither wise nor just, but it makes up for all its folly and injustice by being damnably sentimental.

Extinguished theologians lie about the cradle of every science as the strangled snakes beside that of Hercules; and history records that whenever science and orthodoxy have been fairly opposed, the latter has been forced to retire from the lists, bleeding and crushed if not annihilated; scotched, if not slain.

There is no sea more dangerous than the ocean of practical politics none in which there is more need of good pilotage and of a single, unfaltering purpose when the waves rise high.

Trust a witness in all matters in which neither his self-interest, his passions, his prejudices, nor the love of the marvellous is strongly concerned. When they are involved, require corroborative evidence in exact proportion to the contravention of probability by the thing testified.

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