Howard Jacobson: Hark the distant angels sing, plucking a tune on just four strings

We laugh at the heroic in away that would be impossible if we did not venerate it

And a thousand ukuleles played ... I will explain that, but first a paragraph or two in praise of the mock-heroic. The mock-heroic, according to Ulrich Broich, author of The Eighteenth-Century Mock-Heroic Poem, expressed "the discrepancy between the epic ideal and the impossibility of realising that ideal". You could argue, therefore, that the form has life only so long as there is an epic ideal out there to which we aspire, but feel we are inadequate. Thus we wouldn't write Don Quixote today because we don't dream of riding out into a naughty world and doing noble deeds.

It was Romanticism, Broich argues, which put paid to the mock-heroic as a literary form. With Romanticism, reading expectations changed. The poet was now a man writing to men – all men – not to a small, classically educated élite. Imitating the classics went out of fashion. Satire remained, but the mock-heroic was more than satire in that it worked best when it participated in the form it parodied. In other words, you have to enjoy the conventions of the heroic in order to get the mock-heroic.

"Marcus noster stultus est", our Latin master used to make us sing around the piano, "stultior, stultissimus". Which roughly translated means: "Our Marcus is a tit, more of a tit, a total tit." Apart from helping us bone up on comparatives and superlatives, the idea was that we would find it refreshingly amusing to put Marcus through ascending degrees of dick-headedness in nursery Latin because the Latin we customarily read in class – Caesar's Gallic Wars or The Aeneid – was sonorously heroic. I would like to be able to tell you that the discrepancy had us rolling around laughing in our desks, but alas, reader, it did not. That said, stupid Marcus would certainly mean a lot less to pupils of an inner-London comprehensive whose only approximation to a humane education is Media Studies.

Whatever has happened to the mock-heroic as a literary exercise, I believe it remains alive and well in British culture. We might have borrowed the form from the Italians and the Spanish originally, but it suits our temperament. We laugh at the heroic in a way that would be impossible if we didn't also venerate it. We deride ceremony while being among the most ceremonious people on the planet. Take a figure like Stephen Fry, without whom not an hour's radio or television would be considered complete. Why is he beloved of the English middle classes? Because he is both pomp and pomp's parody.

I am a succour for pomp, not for myself exactly, but for other people. Nothing pleases me more than to stroll out of St James's Park, where I go to admire the pelicans – the ultimate mock-heroic bird – and find myself at Buckingham Palace when the guards are being changed, or the Queen's colours are being trooped. At such moments, I think those who would make us into a republic must be deranged. Such innocent pageantry, such a vivid commemoration of an epic past, such fun for the horses, such a joy to the tourists, and such an economic advantage to us. That we cannot wait to make fun of it detracts nothing from the ceremony. We mock it best not when we hate it (whoever met a republican with a sense of the ridiculous?) but when we love it.

Which brings me back to the thousand ukuleles raised aloft at the Royal Albert Hall last week – and our attitude to Albert memorials is another instance of mock-heroic even if the memorials themselves are not. The event in question was a Promenade concert given by the Ukulele Orchestra of Great Britain. I have written enthusiastically about the Ukulele Orchestra of Great Britain before, but that was in the days when their brilliant virtuosity was known only to a select few, whereas now they can fill the Albert Hall to bursting. Shame that. I enjoyed thinking they were playing just for me. But nice, no doubt, for them.

Although there was surprise in some quarters when their booking was announced for, while they call themselves an orchestra, they are not to be confused with the Vienna Philharmonic, the Ukes (as we original aficionados still like to call them) exemplify the spirit of the Proms, in that they popularise the serious and make serious what is popular, in that they desolemnise without demeaning, in short, in that they mock what is heroic without heroising the act of mockery. Whether that was quite how the 6,000 people jamming the Albert Hall would have put it is neither here nor there. It falls to some people to enjoy life, and others to tell them why they are enjoying it. But the evening was a thunderous success, however one describes it.

As a small object sent on a large errand, the ukulele is itself the quintessence of mock-heroic. This was understood by George Formby, for whom the Ukes have little time (though their version of "I'm Leaning on a Lamppost" played as Russian folk song lingers long in the mind). Formby's crude northern sexualising of the metaphor in songs such as "With my little Ukulele in my Hand" might have appalled Lord Reith but, in fairness, it only released a discrepancy between an epic ideal and the impossibility of realising it which is already inherent in the instrument.

The Ukulele Orchestra pulled off a more refined version by inviting a thousand people to bring their ukuleles along and combine in a mass four-stringed rendition of Beethoven's "Ode to Joy". I am no student of the German mock-heroic but I'd be surprised if Beethoven would have been much amused had he walked in. How far we'd have got explaining that the ukulele is in fact the ideal means of expressing the work's essentially grandiose preposterousness – and we mean that as a compliment, Ludwig - I have no idea.

But those thousand ukuleles revealed an unexpectedly wistful melancholy in the work. It was like listening to distant angels singing to themselves. And thus we discovered a capacity for wistful melancholy in the ukulele too, which surprised us into a strange quiet.

Why, when it was all over, the sight of a thousand ukulele players mock-heroically waving their instruments above their heads was so affecting is something I will not even try to understand. But I am thankful the mock-heroic exists to save us from the fatal seductions of mass emotion. Seid umschlungen, Millionen! – Be embraced, you millions! – be damned.