Why a jacket is the making of a man

What, when it comes to clothes, is truly worth the money? The question is much rehearsed and, for men, has a consensus answer: shoes. You can tell a lot about a man by his shoes, the saying goes. There is sense in this. Good shoes — leather ones, anyway — have a shape, colour and texture that cannot be faked. Properly cared for, whether they are Oxfords or motorcycle boots, they last many times longer, too.

There is another answer to the question, though, and a better one: dollar for dollar, wear for wear, what makes a man look and feel best is a killer jacket.

I mean the word in its widest possible sense here. A jacket, in its platonic essence, has only two characteristics. It is a second layer worn on the upper body, and it opens at the front. Under this definition fit sports coats and blazers, jean jackets, blousons and bombers, leather jackets in all their flavours, Harringtons, chore coats, overshirts in cashmere or polyester, Eisenhowers and varsitys, and much else.

Why is the jacket so powerful? Several points stand out. Jackets provide shape. They are puffy, or they have a waist, or they add shoulder, or they drape and billow. Shape adds interest and a chance to conceal whatever needs concealing. Shirts, which are a single layer of thin cloth, struggle on this front. Just the fact that jackets are a second layer adds complexity and a suggestion of aesthetic intent. There is something about them that suggests an effort at presentation. They are stylish by nature.

There is an alternative second layer: the sweater (that’s a jumper, if you speak English rather than American). They are inferior in almost every respect. Good knitwear is ruinously expensive. With the honourable exception of the cardigan — that prince among sweaters and near-jackets — it is hard to adjust a sweater for temperature by opening a button or zipper. They are easily damaged and attract moths. They get dirty quickly. The moment I accepted that sweaters, barring a turtleneck here or there, were never going to play much of a role in my wardrobe, was a relief.

Then there are practical aspects. Most jackets have several pockets and, unlike a pair of trousers, a jacket remains comfortable when it contains a wallet, a phone, a notebook, a pint of bourbon or whatever else.

If you wear a jacket constantly it simply becomes your thing, like your hair or your smile

More importantly, jackets are economical. Not because they are inexpensive per se, but because you don’t need very many of them. A jacket is something you can wear frequently without embarrassment or constant cleaning: not a claim that can be made for trousers (with the exception of jeans) or shirts. If you wear a jacket constantly it simply becomes your thing, like your hair or your smile.

Indeed, a good jacket can be cheap. How much can you spend on a Carhartt or a bleu de travail? And, because jackets tend to be sturdy things, there are loads of beautiful ones available second-hand. Most styles do not have to be precisely fitted, either. Once you learn your own measurements and how certain brands fit, buying jackets online can be habit-forming. If there isn’t a 12-step programme for people who are throwing their lives away buying vintage sport coats on eBay, I may have to start one.

Summer, when a second layer is not appealing, is the challenge for jackets. For work or a wedding, an unlined blazer in hopsack is a universal solution. In more casual settings, a short-sleeved shirt with a collar worn unbuttoned or partly buttoned over a T-shirt is a cool (in both senses) second layer.

In my case, my three essential jackets are a denim chore coat, a boxy blue number in heavy blue corduroy, and one or the other of my tweed sport coats in a straight (and therefore forgiving) American cut. Another man, of a different shape and taste, would have a totally different arsenal. The point is just when you set about, to use a horrific phrase, “building a wardrobe”, you are more than halfway there once you have a couple of jackets you really like. When you find one, shut your eyes to the price tag and just buy it.

Find out about our latest stories first — follow @financialtimesfashion on Instagram — and subscribe to our podcast Life & Art wherever you listen