A change is as good as a rest, which is why I felt after my two-week dash around the Americas as though I’d been away for a month. It’s also why you should leave your office at lunchtime, even if it’s just for five minutes, to go outside, smell the air and have a look around. Your eyes and brain will thank you for it.

I am especially lucky, because if I leave the office for five minutes I find myself in Hatton Garden, home to dozens of jewellers of every stripe, all of whom display a tempting selection of wares in their windows. After a morning of spreadsheets and wireframes I can feast my eyes on the finest jewels in the city, and come back to the office boosted and sprightly and ready to work. Beautiful things, you see, make me happy – and when I’m happy I get more done.

I’m not unique in this. We all prefer a window seat, because we like to look at things, and hotel rooms with a view of the sea cost more than those without, because we especially like to look at the sea. The sea, you see, is beautiful. I like to write, but at home I often struggle to think of things to write about. Send me away to the seaside and within a day I’ll have dreamt up (literally: all my ideas come to me in dreams) five new stories and the basis of a blog rant. Send me away to the countryside, where I can look at flowers and grass and trees, and the same thing happens. In the absence of trees and seas, though, jewels will do the trick. My brain gets switched on, new connections get made and I come back to my desk with the answer to a problem that’s had me stumped all morning.

So beauty makes me, and probably you, happier and more productive. And I have always believed that happiness and physical health are directly and causally linked, not for hippy-dippy reasons but for the sound scientific reason that your mind is part of your body, and its health is as key to your overall physical well-being as that of any other body part. Which means that keeping people happy helps to stop them from getting sick, and stopping them from getting sick reduces the cost of making them well again, which is why beautiful things should be available to everyone on the NHS.

Fortunately, though, looking through the window of a jeweller remains free, as does looking at the sea, or the sky, or Marilyn Monroe or a Picasso. Beauty may only be skin deep, but it can gladden the heart as well as the eye.