'We laugh," said Lord Byron of his fellow-Englishmen, "that we may not weep." There is something heroic about such stoicism, whose smile may simply be an extension of the stiff upper lip, but something a little sad as well, since it suggests a refusal to confront an underlying emotion.
Not that the English have any monopoly on protective self-irony. The French, too, have prided themselves on being able to laugh away even intense suffering. "Dying must be very hard," an awestruck admirer once whispered to Gustave Flaubert, only to be told brusquely: "Not half so hard as writing a novel."
No wonder that the philosopher Nietzsche concluded that every joke was really just an epitaph on an emotion. That brilliant remark reads like the perfect justification for the subordination of the comic element in so many classics of German literature.
Psychoanalysts have always contended that there is an intimate link between jokes and the unconscious. And they are surely right. Those wisecracks made about Paddies in bars from Wigan to Watford reveal less about the innate foolishness of the Irish than they do about the Englishman's persistent and poignant desire, once in his life, to say something funny.
Ever since the European Enlightenment, virtues have been seen as personal, while vices are most often treated as national. These days, powerful people understand that it is crass to laugh at foreigners (on whose cheap labour they invariably rely), so they often employ foreigners to do the laughing for them.
Clive James, that fine poet and clever Aussie, appears regularly on BBC television to mock Japanese quiz-shows and Paraguayan goalkeepers on behalf of a British viewership too subtle to produce such slapstick itself. By a somewhat similar process, Borat is now permitting even politically-sensitive American liberals to laugh at Kazakhstan (and other things as well).
But most of this comedy is about transgressing the narrow range of allowed opinion in multicultural societies rather than about summing up some essential quality in a national or ethnic group.
Which gives rise to a question. Is there, in this age of multicultural societies, any longer a truly Jewish, American or even Irish joke? The sheer interchangeability of the quips made about each of these groups suggests that there isn't.
But maybe it was ever thus. The Kerry jokes told in 1970s Dublin (at the height of the GAA football rivalry) had all been told, years earlier in New York, of the Poles. Samuel Beckett once morosely observed, on reading yet another awful riddle from a Christmas-cracker: "There are only two kinds of joke - those that were once funny and those that were never funny."
As the season of mince pies approaches, so does the prospect of squiffed old buffers standing in front of log-fires to retell their favourite gags. Most compulsive jokers are shy, insecure persons, who tell their party piece as a way of securing social acceptance without having to submit to the risks of two-way conversation.
Having a good sense of humour isn't at all the same thing as having a propensity to tell jokes. It has more to do with possessing a particular cast of mind which reveals itself suddenly in a moment of pressure. And, in that department at least, national and ethnic characteristics persist, especially whenever the topic turns to religion.
Anger with the Almighty marks Irish wit. Asked what he thought of the life to come, Joyce said he didn't think much of this one. Seán Ó Ríordáin said "má tá Dia ann, is bastard ceart é". Kenneth Tynan was right to say that the Irish express a very deep grudge against God which the merely godless would never feel. Contrast that with the almost wistful, anti-climactic humour of Woody Allen's lament: "Not only is there no God, but try getting a plumber on Sundays."
The Protestant Swiss take a more pragmatic view. When one of their church spires was damaged by lightning, its rector found parishioners strangely unwilling to stump up money. "If God chooses to set fire to his own building," they reasoned, "why should we pay for the restoration?"
While the Irish rage, the Americans sigh and the Swiss reason, the Jews (as always) wait. They tell the story of a poor father of a large family who was unemployed for many years. Eventually, taking pity on him, village elders gave him a post as a sentry, to look out for the Messiah. After many weeks, he complained of the poor pay and that his kids were still hungry. But the elders would have none of it. "Your post could not be a more important one," they consoled him with soulful deliberation. "And besides," added one of the wisest men of all, "it's a permanent job."
Now, may I have my mince pies?