"A joke is not a thing but a process, a trick you play on the listener's mind. You start him off toward a plausible goal, and then by a sudden twist you land him nowhere at all or just where he didn't expect to go."

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The goal towards which the pleasure principle impels us - of becoming happy - is not attainable: yet we may not - nay, cannot - give up the efforts to come nearer to realization of it by some means or other.

— Sigmund Freud