"Nothing," writes Amelot, "pleases less than a perpetual pleasantry," and we all know that a jest-book is dull reading. Humour seems the more fugitive, because we do not know by what means to reproduce and continue it. We can, almost at will, call up emotions of love, hatred or sorrow, and when we feel them we can aggravate them to any extent, but humour is not thus under our command. We cannot invent or summon it. When we have heard a "good thing" said, we shall find that the mere repetition of the words originally uttered are more fully successful in reproducing and prolonging our mirth than all the attempts we usually make to develop it and come closer to the point. Sydney Smith was of opinion that much might be effected by perseverance, and this is the reason that he was often guilty of that bad and overstrained wit which led Lord Brougham to call him "too much of a Jack pudding." We cannot by calculation and design produce anything worthy of the name of humour. It is generally true that any kind of reflection is inimical to it. But no doubt the great cause of its evanescence is that it leads to nothing, and adds nothing to our information. The most fleeting humour is that which is on unimportant subjects, as in comic poems and squibs, which may show considerable ingenuity, but have no interest. It is the nugatory and negative character of humour that makes it so short-lived. Hence, also, it is best at intervals, and in small quantities. The fact that when any attempt is made to explain a jest and glean any information from it the humour vanishes, seems much opposed to its containing any principle of rebirth. Many of the philosophers, who have discarded the idea of there being condemnation in the ludicrous, have been misled either by not distinguishing between the ludicrous and the gift of humour, or by regarding the grain of truth which is imbedded in all wit as the entire or principal cause of our amusement. To form the complication necessary for humorous sayings there must be, of course, some element of truth to oppose the falsity in them. The course in forming witty sayings is generally the following. We remark some real resemblance between things which has hitherto been unnoticed. We then, upon this foundation, make a false statement, deriving so much colour from the truth that we cannot easily disengage one from the other. The resemblance must be something striking and unusual, or it would not support a statement which opposes our ordinary experience. As in the ludicrous there is reality, so in humour there must be some element of truth, or we should regard the invention as simple falsehood. To this extent we are prepared to agree with Boileau that "the basis of all wit is truth," but the result and general impression it gives is falsity. Addison's Genealogy of Humour:-- Truth Good Sense Wit Mirth Humour