There is, I am almost sure, a funny world out there. Prince Charles, Ann "Dancing Queen" Widdecombe, Katie Price, Huw Edwards, Wayne Rooney's vice-girls, the Speaker of the House of Commons: no one could seriously deny that the raw material for a great carnival of comedy is to be found every day in our public life. Yet increasingly we seem to live in post-humorous society in which nothing is funny, particularly if it is meant to be funny. Those who argue that, in a brutal world spiralling ever downwards to perdition, jokes are inappropriate seem to be winning the battle.
This gloomy thought first occurred to me a few years back when I read Martin Amis's novel Yellow Dog to find that, mysteriously and heartbreakingly, the style of a writer whose joyful comic exuberance had always been such a treat was now flat-footed and self-parodic. Perhaps, I thought, the fault was not Amis's but the world around him.
It happened again this week when I saw No Pressure, Richard Curtis's short film which was meant to make the case, comically, for environmental awareness, but turned out to be a propaganda own-goal of spectacular proportions. It was not so much the ill thought-out message which was worrying, as the weird humourlessness of the whole thing.
Curtis has always understood comedy; his style has been good-hearted and character-based. On this occasion, though, he must have sat around with his team and agreed that, yes, it would be funny to show environmentalists blowing up those who failed to listen to them. From the most unexpected source, it was an imitation joke, humour for those without a sense of humour. You would actually have to be quite odd to find it funny or convincing.
Perhaps the post-humorists are right, and any comic attempt to deal with global warming is by its nature doomed. Certainly the British, having prided themselves on their sense of humour throughout most of the 20th century, are becoming increasingly po-faced. Figures released this week for a TV trade fair in Cannes reveal that, although Britain sells more programmes than ever to foreign markets, they tend to be reality shows (Strictly Come Dancing, Masterchef) or drama (Spooks, Dr Who). Comedy hardly gets a look-in.
Inevitably, when the tide of humour is at a low ebb, people start harking back to a lost golden age. The Prince of Wales, in a foreword to a book called Growing Up With the Goons, wrote that his favourite comedy from the 1950s will still appeal to "anyone wanting a respite from today's fashion for witless humour and smut". The death of Norman Wisdom has inspired the usual chorus of why-of-whyers reminiscing about the gentle laughter of yesteryear.
Oldsters should probably be ignored when it comes to comedy. Loyalty to the Goons, Norman Wisdom, Dad's Army or Charlie Drake is less about humour than a longing for the safer, sweeter world of the past. One day, veteran columnists will look back fondly on the laughs we all had watching Brass Eye or The Thick of It and ask where the innocence of old-fashioned comedy has gone.
Yet given the grim hilarity of our public life, it is odd how few people are making good jokes about it. The fault lies partly with our increasingly timorous TV executives, whose response to a world ripe for parody is to put on spoof quiz shows in which stand-up comics are invited to take a pop at obvious targets, uncritically reflecting audiences' own assumptions and prejudices. But, beyond TV, a general, disapproving humorlessness is in the air.
The best comedy is discomfiting and against the grain of public opinion. It should niggle away at normality, burrow under the surface of modern life to laugh at its wilder absurdities – liberal environmentalists giggling about blowing up non-believers, for example. "As long as we can laugh – at our aspirations as at our disillusionments, at our fears and our pretensions and our vanities and our appetites; above all, at ourselves, there is still hope for us," Malcolm Muggeridge wrote almost 50 years ago. Few of St Mugg's pronouncements have grown truer over time, but that one has.