The choice between a short sleeve and a long sleeve linen shirt looks like a question of temperature and turns out to be a question of circumstance. Both are cool. Both are correct in warm weather. Yet each does certain things the other cannot, and a man who owns one of each will find that he reaches for them on different days for reasons that have little to do with the thermometer. The comparison is worth making carefully, because it determines how many shirts a suitcase needs and which ones.

Start with the assumption that shorter means cooler. In shade and in still, humid air it is true: bare forearms release heat, and a short sleeve allows more air to circulate around the upper arm. In direct sun the matter is less clear. Skin exposed to strong sunlight absorbs heat directly, and a loose sleeve of pale linen shades the arm while the open weave continues to let air through. This is why the traditional dress of the hottest inhabited regions tends to be long and loose. A linen long sleeve on an exposed hillside or an open deck can be the more comfortable garment by the afternoon, and it spares the forearms a day of sun.

The rolled sleeve is the long-sleeve shirt's particular advantage. Turned back twice to just below the elbow, it gives nearly the ventilation of a short sleeve with a different line: a little weight at the forearm, a suggestion that the wearer has dressed and then relaxed. It can be unrolled when the sun is strong, when the air conditioning is cold or when the occasion becomes more formal. A short sleeve has one position. Against that, a rolled sleeve in linen will be creased when it comes down again, and it is as well to decide at the start of an evening which way it is to be worn.

Formality is the second consideration. The long sleeve is the more formal garment in almost every setting, and in some it is required. Mosques that admit visitors ask men for long trousers and covered shoulders, and a long sleeve is the considerate choice. Opera houses, older private clubs and a number of hotel dining rooms expect a long sleeve in the evening, whether or not they write it down. Under a jacket only a long sleeve is correct, since the cuff is meant to show. The short sleeve belongs to the day: lunch by the water, the harbour, the beach club, the market, the drive. It is not careless, but it announces leisure, and there are tables at which that is the wrong announcement.

Proportion is the third, and the one most often ignored. A short sleeve draws a horizontal line across the upper arm and shows the forearm. It suits shorts naturally, because the two garments share a logic, and it sits well with trousers in the daytime. A long sleeve lengthens the line of the arm and balances long trousers particularly well. Worn with shorts, a long-sleeve shirt with the sleeves rolled is a classic combination, relaxed above and below; worn buttoned to the wrist with shorts it can look undecided. Neither rule is absolute, and both are worth knowing before breaking.

In the PP collection the comparison is unusually direct, because the same shirt is made both ways. The Laos Short Sleeve Linen Shirt is offered in twelve colourways: White, Oyster, Vanille, Beige Cream, Sky Blue, Light Blue, Mint Green, Lemon Yellow, Pink, Coral Orange, Violet and Dubarry. The Laos Long Sleeve Linen Shirt is offered in three, Oyster, Beige Cream and Dark Blue. The spread is deliberate in its effect, whatever its origin. The short sleeve carries the colour of the wardrobe; the long sleeve carries the neutrals and the dark, which are the tones that evenings and dress codes ask for. Both close with seashell buttons.

How the two travel is a practical point. A short-sleeve shirt takes slightly less room and has no cuffs or sleeve plackets to press. A long-sleeve shirt asks for a little more care in folding, with the sleeves laid flat along the body. Both crease in transit, as all linen does, and both recover with a steamer or a few minutes of hanging in a damp bathroom. The Journal's guides to the Laos Short Sleeve and to the long-sleeve linen shirt for men treat each garment separately.

For a week somewhere warm, a workable division is two short to one long for a beach or island stay, and the reverse for a city, the Gulf or anywhere evenings are dressed for. A man going to the Cyclades in July might take Laos Short Sleeve Linen Shirts in White and Sky Blue and a single long sleeve in Oyster for wind and late dinners. A man going to Muscat or Dubai in January would do better with long sleeves in Oyster and Dark Blue and one short sleeve in Vanille for the resort. Both Laos shirts are handmade in PP's Dubai atelier and in Belgium.

If only one can be chosen, the long sleeve is the more versatile shirt, because it can do an imitation of the short one and the reverse is not possible. If two can be chosen, the answer is one of each, and the confidence to know which day is which.

The PP Laos Shirt Guide  ·  The Linen Shirt Fit Guide  ·  How to Style a Linen Shirt for Men