It may be a reflection of growing older.

That, or this bleak time of year. Whatever the cause, I have found myself seeking out books that will offer a touch of cheer, in the hope they will do something to counteract the lack of light and the diet of truly terrible news we are fed, each and every day.

Reading David Grossman's heartwrenching new novel, Falling Out Of Time, about parents grieving for their dead children, I was glad I was not wearing mascara. Or in public.

I used to feel irritated when friends asked for recommendations of what to read, but then told me how depressing or morbid they found the books I had suggested. It felt like a personal affront. What was life about if not to be taken seriously? Fiction's purpose - or one of them - is surely to alert readers to the dark or difficult or painful side of life, to give a voice to those previously hushed or hidden.

Now, I begin to understand why instead of embracing contemporary angst these refusniks preferred to reach for a sensible biography, or the lawnmower. Several decades into a life in which too many hours have been spent reading about fictional child abuse, sexual slavery, genocide or the aftermath of natural disaster, I am beginning to envy those with a garden shed to retreat to.

Before anyone accuses me of being heartless or shallow - though both things may be true - let me say that the list of my all-time favourite books would be dark and serious indeed. Writers such as Dostoevsky, Malamud and JM Coetzee would far outrank most of those for whom humour comes first, whose slant on life is droll, not despairing. But when you consider the circumstances in which these often harrowing writers were working, their subjects are a reflection of their private travails or, as often in the case of Coetzee, of their fellow countrymen.

Increasingly, however, I wonder why those living in the relative affluence, comfort and safety of the world's most privileged countries - at a time unparalleled in history for health and ease and charity - are almost magnetically drawn still to the horrors of humanity, be it those we see on the evening news or that suffered by our forebears.

I am not saying these are not entirely valid and valuable subjects. Having recently written about the Battle Of Flodden, I fall into that category myself. What astonishes me, though, is that even though few of us wake up hungry or in fear of our lives, there is still a dearth of humour. Where are the jeux d'esprit to lift the heart and leaven the gloom? Why is misery, in all its forms, the backbone of so much fiction, and humour its little finger?

With few exceptions, among them David Lodge, Howard Jacobson, Lucy Ellmann, Alan Bennett and Alexander McCall Smith - who has almost set himself up as a one-man surgery dispensing good cheer - novelists avoid the comic. Perhaps a fear of slapstick lies at the root of this, or maybe lack of confidence. Being funny, after all, is a great deal more difficult than being sad or shocking.

Although the likes of PG Wodehouse, Flann O'Brien, James Thurber or Garrison Keillor make it look the easiest thing in the world, a humorous voice is the trickiest to pull off. Get the tone wrong, veer towards the twee or the crass or the annoyingly whimsical, and the whole book collapses. Perhaps there ought to be classes on the country's countless creative writing courses, showing how to do it. And a book festival dedicated solely to funny books.

I suspect the deepest fear that holds back those who might otherwise try to brighten up our bookshelves is that of critical disdain. Like children's literature, comic fiction is often deemed a lesser category, not worthy of attention. To be seen to embrace it, or applaud it, is to be revealed as a lightweight. After all, how can something that makes you laugh convey anything serious? To which I would say, try it and see.