It's the time of year for gifts.
Which means the time of year for gratitude, too, though many Christmas presents will evoke the opposite feeling: despair. As Socrates put it one day, when he walked into the bustling Athenian marketplace: "I never knew there was so much stuff I didn't want."
Only, being grateful is good for us. Your mother knew it, when she chastised you for not muttering "Thank you". More recently, psychologists have recognised as much because feeling grateful correlates with feeling happy. Hence the piece of self-help advice to keep a "gratitude diary". Fill it with those daily things for which you can be glad – the helping hand, the warm hello.
But then again, what happens when you don't feel thanks – when you unwrap the present and it's a gaudy shirt you wouldn't wear in a pantomime? Your first thought is not "Thanks" but, "Can I exchange it?" The problem is that gratitude cannot be reverse engineered. True thanks arises spontaneously. It's not contrived. (Like a fake smile, fake thanks show in the eyes.)
At base, gratitude arises from existence – the how-wonderful-life-is-because-you-are kind of thanks. And the word "existence" contains a clue. It's like the word "exit". It means to be placed outside. So thanks is offered to the source of your existence. Gratitude is the recognition that life itself is the gift.
Mark Vernon's new book is The Good Life (Hodder, £12.99). Visit theschooloflife.com
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