I don’t know whether it’s in the Anglo bit, or on the Saxon side, but there’s a chromosome somewhere in the DNA of the British that gives our bodies a very different chemistry from the rest of the world’s.

We are the only people I know of who find chemical stimulants physically relaxing. Other nations use caffeine in the same way doctors use adrenalin and Trident submarines use enriched uranium — as a dangerously powerful means of propulsion best delivered carefully by the microgram. We ingest caffeine, through tea, as though we were whales draining the Southern Ocean in search of plankton — by the hundreds of gallons and without a second thought. And yet we are not all the goggle-eyed Duracell bunnies you might expect, because we find tea, by some Anglo-Saxon alchemy, curiously calming. The same goes for grand opera, war films and stories about Silvio Berlusconi’s love life. Other nations find all of the above pulse-raising while we Brits find them, in different ways, a source of reassurance and a comforting aid to a good night’s sleep.

This trait finds its fullest expression in the British attitude towards the thriller. There is no more relaxing read for a Brit than 280 pages of deception, treachery, chase, pursuit, wrongful arrest, bungled escape, pistol-whipping, espionage and murder. A thriller with a corkscrew narrative and machinegun tempo can induce in the reader a state of blissed-out relaxation more comprehensive than any yet achieved by years of the down-dog yoga position and sun salutations.

One of the most addictive thriller writers ever, and by extension one of the most enjoyably relaxing of novelists I know, has his centenary this year and, to their eternal credit, Penguin Modern Classics are reprinting several of his best. Eric Ambler is one of the most underrated 20th-century writers, occupying territory somewhere between John Buchan and le Carré, and outpacing them both. His best work was written in the late Thirties. Like Buchan before him, his heroes are innocents forced to draw on resources they did not realise they had. They are adrift in a Europe on the eve of war, with allegiances shifting and authority as likely to be treacherous as reassuring.

Ambler’s works are entertainments, but he is such a fine and observant writer, with such a brilliant feel for atmosphere and culture, that his narrative helps to illuminate, better than almost any other fiction of the time, the politics of the Thirties. The violent seediness of Italian fascism, the precarious legitimacy of Balkan thrones, the shabby, compromised but essential decency of democratic Britain and Third Republic France, and the romantic appeal of Communism as the most uncompromisingly vigorous element in the popular front against dictatorship; all the confused reactions of that time are rendered with conviction.

But the real pleasure of classic Ambler — The Mask of Dimitrios, Cause for Alarm, Epitaph for a Spy — is seeing the author do for novels what Morgan does for sports cars. He turns out something world class yet quintessentially English, something that is undeniably thrilling but ultimately incredibly reassuring.

Truth in the tailoring One of Ambler’s many joys is the way in which he uses details of clothing to reveal so much of character. In a world of shifting alliances and covert identities tailoring can reveal a character’s true allegiance. The width of a hat brim or the jut of a collar can separate a disguised Swiss-German from a bogus Yugoslav in a Milanese arms deal. And so it goes today. See someone in a tweed sports coat, with properly pressed cords, a well-ironed shirt and a waxed jacket to hand and, of course, it goes without saying, you’re in the presence of a classic Italian tourist. Pinstripes? An American. Oxford shoes? French. The old money look of studied ease and broad acres captured so wonderfully by a polo shirt and chinos? Either Uruguayan or South Korean. Clothes are still a powerful signifier of fundamental allegiances, but the issue today is that more and more people appear to owe their fundamental allegiance to Ralph Lauren.

Cavaliers and roundheads Clothes have always been signifiers not just of national, but class, allegiance. And never more than by what you put on your head. The classic Frost Report sketch in which John Cleese, Ronnie Barker and Ronnie Corbett represent upper, middle and working class Britons communicated their status by dressing the three, respectively, in bowler hat, pork pie-ish trilby and flat cap.

In the world according to Ralph Lauren, the only acceptable headgear now appears to be the baseball cap. But I think I have detected a subtler way of signalling social distinctiveness.

Travelling round the country last week I noticed that the one sure guide to how wealthy an area was lay not in the number of delis, but in the length of boys’ hair. The invariable rule seemed to be, the longer the schoolboy mops, the more well heeled the community. I began to wonder if there was some Samson-like link between hair length and economic strength. Have any other readers noticed this trend? Is this a cavalier/roundhead thing? Or was it just that hair cutting had been suspended for half-term?

Michael Gove is the Conservative MP for Surrey Heath

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