笑口常开 (xiào kǒu cháng kāi) — May the Laughing Mouth Stay Open · Lasting Good Cheer

Walk into the first hall of almost any Chinese Buddhist temple and the figure that greets you is laughing. He is 弥勒佛 (Mílèfó) in his folk form — the round-bellied, bare-chested monk the West calls the Laughing Buddha, modeled on 布袋和尚, the wandering Cloth-Bag Monk of tenth-century Zhejiang. Flanking him, on the pillars of the Maitreya hall, hangs the couplet that fixed the phrase in the language: 大肚能容，容天下难容之事；笑口常开，笑世间可笑之人 — a great belly that can hold what the world cannot, a laughing mouth that stays open, laughing at the world's laughable people. 笑口常开 is the second line of that couplet, and the temple is where most Chinese first read it.

The four characters divide cleanly into two halves. 笑口 (xiào kǒu) is the laughing mouth — 笑, the figure of a person doubled over in mirth, and 口, the simple square of an open mouth. 常开 (cháng kāi) is the predicate: 常, constantly or as a rule, and 开, to open. The whole reads not "laugh sometimes" but "the mouth stays open as a settled condition" — joy as a steady state rather than a passing fit. The image is older than the temple couplet. 《庄子》counts the open-mouthed laugh as the rarest thing in a human life, and Tang poets kept returning to it: 杜牧 sighed that 尘世难逢开口笑, a hearty laugh is hard to come by in the dusty world, while 白居易 turned it into advice — 不开口笑是痴人, the one who never opens his mouth to laugh is a fool. 笑口常开 answers all three: it wishes the rare thing made constant.

What folk usage added to the temple image was a quiet claim about the body. The proverb 笑一笑，十年少 — one laugh, ten years younger — paired the open mouth with long life, and 笑口常开 inherited that reading. Spoken as a blessing it asks for more than a cheerful mood; it asks for the kind of constitutional gladness that is supposed to keep a person well. By the Ming and Qing the phrase had left the temple pillar and entered New Year couplets and birthday scrolls, where it has stayed — a wish for the laughing mouth to remain open through whatever the year brings.

• 其中开口而笑者，一月之中不过四五日而已矣。

  《庄子·盗跖》(Zhuangzi, "Robber Zhi," c. 3rd c. BCE)
  Of the days a person truly opens the mouth to laugh, in a whole month there are no more than four or five. — Zhuangzi's bleak arithmetic of a lifetime, set against illness, loss, and worry. It is the locus classicus of the open-mouthed laugh as something scarce and precious — the very scarcity the blessing 笑口常开 sets out to overturn.

• 尘世难逢开口笑，菊花须插满头归。

  杜牧《九日齐山登高》(Du Mu, "Climbing Mount Qi on the Double Ninth," c. 845)
  A hearty laugh is hard to come by in this dusty world — so fill your head with chrysanthemums and go home. — Du Mu on a festival hilltop, taking Zhuangzi's scarcity as a reason to seize the laughter while it is here. The line made 开口笑 a byword for joy snatched against the odds.

• 随富随贫且欢乐，不开口笑是痴人。

  白居易《对酒五首·其二》(Bai Juyi, "Facing Wine, No. 2," c. 9th c.)
  Rich or poor, just be glad — the one who never opens his mouth to laugh is a fool. — Bai Juyi turns the old lament into plain counsel: gladness is a choice available in any circumstance. Read beside 笑口常开, it is the same wish in the imperative — keep the mouth open, whatever the year holds.

The phrase travels as a face before it travels as writing. The Laughing Buddha — 弥勒佛 in the temple, the round figure rubbed shiny on countless shop counters and dashboards — is 笑口常开 rendered in clay and bronze, and his couplet (大肚能容…笑口常开…) is among the most quoted in Chinese Buddhism, painted at 北京潭柘寺, 杭州灵隐寺, and Maitreya halls across the country. To wish someone 笑口常开 is, in a quiet way, to wish them the monk's temperament: a belly wide enough to hold what cannot be changed and a mouth that laughs anyway.

As writing, 笑口常开 belongs to the cheer end of the blessing vocabulary, where it often pairs with 福 — the New Year couplet 笑口常开迎百福 reads the open mouth as the thing a hundred blessings come to meet. It is most given to elders, on the strength of the folk line 笑一笑，十年少, which makes a glad face a kind of medicine; and to close friends, where it is less a ceremonial wish than an affectionate instruction — stay the way you are, keep laughing. Unlike the prosperity phrases, it asks for nothing the recipient must achieve, only for the disposition that makes the rest worth having.