Howard Jacobson: If you really want to seek the truth, don't expect to find it in a television documentary

Where there's aesthetics there's art, and where there's art there's artifice

Today's lesson: never trust a man who tells you he has documentary evidence. Which amounts to saying never trust a man who makes documentaries. Or it would amount to saying that were documentary evidence what we now expect to find in a documentary. That we aren't sure what to expect from documentaries today tells us as much about ourselves as about the people who make them. Half the time we want truth, half the time we don't.

I can't make my own mind up about the Alzheimer's sufferer's death that wasn't. I knew I didn't want to watch it, but that's about me not the programme. The guardians of public morality have managed - as guardians of public morality often do - to look both ways on the subject, one moment outraged that television is breaking the last taboo and showing us a death, the next outraged that it isn't actually a death we're watching. Had this been cinema some of us would have been banging on the manager's door, demanding the price of our admission back.

Going, going, gone ... does it matter precisely where in that process of departure the camera decides to avert its gaze? Yes, if we're pedants or voyeurs, if it's the "gone" and nothing but the "gone" - the actual moment of expiry - that we insist on seeing. No, if we feel the story has been fully told, whether we see the soul escape the body or we don't. Either way, those who titillate us into watching have something to answer for. First a low opinion of us; second making promises they can't keep.

In the end you have to be on the side of the pedant, otherwise there's no faith left between the promulgators of programmes and their viewers. You said you'd give us death, Mr Watson, or Mr Grade or whoever, so anything less is falsification. From a maker of documentaries we are entitled to insist on documentary evidence.

Which raises the question of whether there really can be such a thing as a documentary in the first place. Enter someone with an idea of how a thing should look and you have aesthetics, and where there's aesthetics there's art, and where there's art there's artifice. Now quadruple that to take account of the aesthetic of the director, the cameraman, the sound recordist and the editor, and you've got art at loggerheads with art. That strict documentary truth gets lost along the way should not surprise us. Stop asking for it, I say. It doesn't exist. Just enjoy the art. Which enjoins upon the programme-maker the obligation to admit it's art he's making.

The first television documentary I made - made as in wrote and presented, not made as in made - was based on an Australian travel book I'd written a few years earlier. Since a travel book is itself a species of documentary I had already had to face some of the criticism to which a documentary in any form exposes you.

I had not, some of my detractors complained, told it as it was. A surprise to me, since I thought my job as a travel writer was to tell it how I saw it. Indeed, when it came to film the book, my producer noted that some of what I'd seen did not exist and was for that reason difficult to catch on camera. My reply, that nothing exists but as we see it, might have been philosophically challenging, but didn't help with the making of the programme. But even this didn't prepare me for the subsequent accusation from some television critics that a scene in which I was alone in the outback with a feral bushman was a lie because in reality there was a crew there filming us.

I never quite got to the bottom of that charge. Of course there was a fucking film crew filming us. Did they think I was beaming myself into their living rooms by auto-transmission? If they meant to imply I was feigning fear when all along I was safe as as houses, they should have seen the film crew. Had the bushman so much as raised a finger, or a centipede crawled across the sound recordist's shoes, they'd have dropped their equipment and run until they got to Darwin. Those of us who didn't sleep on top of the vans that night didn't sleep at all. If there was any untruth in the scene we filmed, it was that we didn't adequately render its terror.

As it happens, we did otherwise deceive the viewer. Every time we saw a kangaroo on the road I yelled at the cameraman to film it. He laughed at me. The whole crew laughed at me. Did I suppose he could shoot a kangaroo just like that - without the long tripod legs, without the light meter, without his baseball hat on back to front, without the director shouting, "Action!" So a dozen kangaroos hopped away unsnapped into the sunset and when we finally needed one we had to film it in a zoo.

Perhaps we should have filmed our failures to film those kangaroos and made a post-modern comedy of it - art showing its pipe work like the Centre Pompidou. We expect that now. We like to see the camera and spot the microphone and overhear the director's questions. Indeed, and paradoxically, we have come to take these devices as evidence of televisual good faith. This must be true, we say, because we see it happening, whereas what we're seeing happening is an object that's already been made.

Reality TV we even call it, as though real life is what's played out for cameras. Well maybe it soon will be. Certainly we are now breeding a species of person who can jump convincingly through the hoops of falsity and still believe - as many a "star" of Wife Swap, say - she's being authentically herself. Big Brother, in a way, proves the opposite - the contestants quickly descending from the lewd vitality of their audition videos into the chaste and dull neuroticism of reality proper. But these are still early days. The real telly people of tomorrow are still being fabricated out there.

Myself, I believe in fiction only. If you want truth, go to fiction. That way there's no deceit, no broken promises, no unmet expectations. Nothing is but how it's seen, therefore choose as your guides those who see it best. And don't ask me what best is. That too cannot be documented. Life's a fable. We interpret it, that's all. As for the illusion which is documentary fact, it's time we gave up our fantasy affair with it.