The word "gift" has got dangerously devalued of late. Salesmen use so-called free gifts as bait and publicists use them as bribes; the wealthy can make "gifts" to their children, or to charities, with no more noble motive than saving tax. And anything labelled a gift shop, or catalogue, can generally be guaranteed to be full of curious, zany items like personalised solid silver back-scratchers and musical ashtrays, which are only classified as "giftware" because nobody in their senses would buy them to use themselves.

We need to claim the word back this Christmas. We also need to claim back the word "generous": which too often gets used in the sense of over-large portions of food, hotel towels, the size of sheets, or women spilling out of their dresses. For generosity--the ability to make real gifts with modesty and love, expecting nothing back--is one of the things which most make us human. You do not find pigs or lions giving one another thoughtful little presents, do you? Monkeys, apparently, offer one another fleas at times, but not in any provable spirit of kindliness. We should honour generosity more than we do.

Perhaps it has become suspect because of the tales of over-the-top generosity sometimes told in gossip about the very rich. The late Christina Onassis giving her daughter a personal zoo and a flock of sheep with their own shepherd, for instance; assorted tycoons flying their guests halfway round the world for birthday parties where there is an emerald bracelet or cufflinks on every place-setting; wealthy men paying off old girlfriends with houses, yachts and Ferraris. In this context, generosity has come to mean that you hurl money around like a drunken sailor. And there is always the suspicion that, like the sailor, you are doing it just to prove that you can afford it. That is not giving: that is showing off.

But the real thing, when you meet it, is magical, and as a quality it belongs equally to rich and poor. Sometimes the poor--like the widow in the Bible who gave her mite--are best at it. Travellers in remote parts, from Poland to Peru, come home with stories of bread, shelter, even beds shared without question with the stranger on the peasant principle that "A guest in the house is God in the house". Nearer home, I loved the stories collected in memory of Katie Sullivan, the 23-year-old mental home care assistant who was murdered last year. Particularly the one about the day she was walking to the pub, and lagged behind, and her student friends caught a glimpse of her emptying her whole purse into a tramp's hands when she thought they weren't looking. Later in the pub they teased her about not drinking, trying to make her admit what she had done; but she steadfastly pretended she didn't want a drink.

Another student I knew, a man, knew that his roommate couldn't afford an important textbook in his subject; a book which was very scarce in second-hand shops and impossibly expensive when new. His friend was far too proud to accept a loan, and so spent a lot of time trekking to the library in the rain to look things up. So the better-off student went to Blackwell's bookshop in Oxford, bought a brand-new copy for 35 pounds, dirtied it up a bit and tore off the paper cover, writing a fictitious name in the front. He even remembered to age the ink by putting it over a radiator, and made a few dogears and faint pencil-marks against what he thought might be significant passages. Then he went home in triumph claiming to have spotted the book in the second-hand bookshop and "beaten them down to two quid". He even got a receipt for the money by buying himself another book at the same secondhand shop. Talk about doing good by stealth: and in case you wonder, I heard the story from the poorer roommate, who had got suspicious and, ten years later, forced the richer one to confess.