In this small, witty, and delightful essay, the writer Jim Holt reflects on what our capacity for joking really tells us about the human condition. It may initially surprise readers to find jokes being the subject of philosophy, but the last couple of years have seen Harry Frankfurt’s brilliant “On Bullshit” reminding us that we can reflect profitably even on what some would regard as the backside of human nature. “Stop Me If You’ve Heard This” (W.W. Norton, 141 pages, $15.95) is a worthy successor.

Mr. Holt is not the first thinker to puzzle over our capacity for laughter. Many philosophers have tried to say something about it, although with limited success. Hobbes thought that the passion of laughter is “a sudden glory arising from some sudden conception of some eminency in ourselves.” But that doesn’t seem quite right: If news arrived that I had been awarded a Nobel Prize, I am not sure I would laugh at it, although I suppose I might.

Kant turned to the element of the unexpected: Laughter is “an affection arising from a strained expectation being suddenly reduced to nothing,” which works for, say, a fart in church, but seems wrong in general, for as the dour Scottish philosopher Alexander Bain pointed out, discord and disorder may be unexpected without being at all funny, like discovering a corpse at a feast.

The banana peel element also excited the French philosopher Henri Bergson. Others have talked of the degradation of dignity in otherwise harmless circumstances, perhaps explaining the wholesome mirth that all good people extracted from President Clinton and his cigar, but also reminding us that jokes and laughter are close cousins to the more sinister mockery and ridicule. It is interesting as well that it is growing children who are prone to ungovernable gales of titters and giggles, which adult life tries to smother under a blanket of po-faced decorum. Such children are equally prone to insecurities and embarrassments, which is also suggestive.

Mr. Holt is well aware that there is something paradoxical about approaching the delicate tensions that sustain a joke with the heavy-handed apparatus of theory. He quotes Max Eastman, who said:

The correct explanation of a joke not only does not sound funny, but it does not sound like a correct explanation. It consists in imagining ourselves totally humourless and most anxiously and minutely concerned with the matter in question, and in realizing that under those queer and uninteresting circumstances a disagreeable feeling would arise exactly where in our mirthful receptivity we experience a comic emotion. That is not funny, and except to the pure love of understanding, it is not fun.

Mr. Holt’s book refutes this last assertion, since it is a lot of fun, even if it falls a little short of Christopher Hitchens’s puff on the dustcover, which calls the book wholesome fun for all the family. It would need to be a pretty well-educated family, and one prone to fits of the giggles.

The invention of the joke is credited by legend to Homer’s character Palamedes, who is also credited with inventing the alphabet, lighthouses, dice, and the practice of eating meals at regular intervals. But the earliest compendium of jokes from classical times turns out to be the “Philogelos,” from the fourth or fifth century C.E. It was followed in due course by a strange assortment of joke collectors. We meet Poggio Bracciolini, an early Renaissance secretary to eight Popes, who seems to have got many of his 273 jokes from a kind of after-hours drinking club of papal scribes and secretaries. Many of Poggio’s jokes seem less than riotous to us, which shows how tastes change. But one struck me as nicely dry: A friar preaching against adultery thundered that it was such an abominable sin that he would prefer to sleep with ten virgins than one married woman; “Many who heard him felt the same way.”

Poggio’s successors include the relentless collector Gershon Legman, and the equally fanatical Nat Schmulowitz, who eventually left his collection of many thousands of volumes to the San Francisco public library, where it still resides, and where Mr. Holt was told that the book in most demand, rather sadly I thought, is “Flagellation and the Flagellants: A History of the Rod in All Countries.”

I hope it was not this experience that depressed him but, in the end, Mr. Holt rather gives up the search for a satisfactory theory of jokes, supposing that there may be nothing significant in common between them after all. He is also perturbed by the finding that there is a very specific area of the brain, the “supplementary motor area” of the left frontal lobe, that can be excited electrically, after which the subject reports finding almost anything side-splittingly funny. Mr. Holt implies that this result rather stymies any attempt at a theory of jokes, but I am not sure that is right. It only means that we would like to discover why some cognitive inputs jolt that particular area while others fail to do so, and why people vary so much in this respect.

There are some excellent jokes illustrating the history and the philosophy in this book, and there are also some highly enjoyable anecdotes. I particularly liked being reminded of the humorless Wittgenstein saying that a philosophy book could be written that consisted entirely of jokes. But I award the palm to a joke unintentionally and obtusely offered by Elliot Oring, who wrote “The Jokes of Sigmund Freud,” and apparently decided that Freud’s sense of humor stemmed from deep ambivalence about his Jewishness, “which could be traced to a childhood episode in which his nanny caught him spitting on the steps.” I do not know whether it was the incongruity or the offense to dignity, or a blast of sudden glory, but I found that absolutely hilarious.

Mr. Blackburn is a professor of philosophy at the University of Cambridge. He is the author of many books, including “Think,” “Being Good,” and “Plato’s Republic.” His book “How to Read Hume” will be published by Granta later this year.