You're listening to a programme from BBC Radio 4.

Good evening. Sir Ken Dodd, who died this week at the age of 90, had some good lines.

With 50,000 jokes up his sleeve, he was bound to, even on the law of averages.

But the best joke about comedy itself came from his near contemporary Bob Monkhouse.

They laughed when I said I wanted to be a comedian, he said.

Well, they're not laughing now.'

Sir Ken was the last of the vaudevillians,

an act that had its roots in music hall

and its humour drawn from the saucy innuendo of the seaside postcard.

He survived into and then prospered alongside a different comic era,

borderline embarrassing personal revelation,

or visceral, sometimes foul-mouthed adjutop that targets anything that might smack of an establishment, often both at the same time.

Humour is subjective, of course. A lot is funny, though I sometimes idly wonder if there'll ever be a

comedian on Radio 4 who doesn't think the late Lady Thatcher was the spawn of the devil.

But at what seems the end of an entertainment era, it's timely to ask what the purpose, the moral purpose of comedy should be.

To make us laugh, happy us up, obviously.

But should it reinforce or challenge the moral consensus of the audience?

Where's the line between satire and abuse, between targets that are acceptable and those that

should be off limits because they're sensitive or vulnerable?

Above all, with faith in our institutions, apparently at an all-time low, at least partly

because of the relentless scorn of the stand-ups, is comedy healthy

for democracy, or does it trivialise and caricature the most serious issues we face,

...