William Hazlitt on the Animal that Laughs and Weeps"Lecture I: Introductory on Wit and Humour" in Lectures on the English Comic Writers (1819), p. 5.
Man is the only animal that laughs and weeps, for he is the only animal that is struck with the difference between what things are and what they ought to be. We weep at what thwarts or exceeds our desires in serious matters; we laugh at what only disappoints our expectations in trifles. We shed tears from sympathy with that which is unreasonable and unnecessary, the absurdity of which provokes our spleen or mirth, rather than any serious reflections on it.
To explain the nature of laughter and tears is to account for the condition of human life; for it is in a manner compounded of these two! It is a tragedy or a comedy — sad or merry, as it happens. The crimes and misfortunes that are inseparable from it, shock and wound the mind when they once seize upon it, and when the pressure can no longer be borne seek relief in tears: the follies and absurdities that men commit, or the odd accidents that befall them, afford us amusement from the very rejection of these false claims upon our sympathy and end in laughter. If every thing that went wrong, every vanity or weakness in another gave us a sensible pang, it would be hard indeed: but as long as the disagreeableness of the consequences of a sudden disaster is kept out of sight by the immediate oddity of the circumstances, and the absurdity or unaccountableness a foolish action is the most striking thing in it, the ludicrous prevails over the pathetic, and we receive pleasure instead of pain from the farce of life which is played before us, and which discomposes our gravity as often as it fails to move our anger or our pity!