Puns

Do you mean to say the pun-question is not clearly settled in your minds? Let me lay down the law upon the subject. Life and language are alike sacred. Homicide and verbicide--that is, violent treatment of a word with fatal results to its legitimate meaning, which is its life--are alike forbidden. Manslaughter, which is the meaning of the one, is the same as man's laughter, which is the end of the other. A pun is primâ facie an insult to the person you are talking with. It implies utter indifference to or sublime contempt for his remarks, no matter how serious. I speak of total depravity, and one says all that is written on the subject is deep raving. [...] A pun does not commonly justify a blow in return. But if a blow were given for such cause, and death ensued, the jury would be judges both of the facts and of the pun, and might, if the latter were of an aggravated character, return a verdict of justifiable homicide.

(Oliver Wendell Holmes: The Autocrat of the Breakfast-Table)

An English sea-captain being asked if he had read "The Exile of Erin," replied: "No, sir, but I should like to anchor on it." Years afterwards, when he had been hanged as a pirate after a career of unparalleled atrocities, the following memorandum was found in the ship's log that he had kept at the time of his reply:

Aug. 3d, 1842. Made a joke on the ex-Isle of Erin. Coldly received. War with the whole world!

(Ambrose Bierce: The Devil's Dictionary)