能ある鷹は爪を隠す
Nō aru taka wa tsume o kakusu The hawk that has ability hides its talons. Those who really can do it are the last to show it.
A cat can sheathe its claws. A hawk cannot. Whatever a goshawk is doing on the falconer’s glove, the talons are there to be seen, curved round the leather. Japanese had a cat version of this proverb too, and the dictionaries still record it, but the saying that survived chose the bird that is physically unable to do what the proverb says it does. That choice is the first clue to what the proverb is really asking for.
What it means
The Daijisen defines the saying flatly: the more real ability a person has, the less it shows on the surface. The larger Nihon kokugo daijiten puts it as a warning against display: someone with true strength does not go around flaunting it. The Daijisen also adds a small usage note that says something about how often the phrase is used. Writing 脳ある鷹, the hawk with a brain, is a mistake, the dictionary says. People only misspell a phrase that often when they say it all the time.
The truth claim is simple: real capability keeps out of sight, and display tends to belong to those who lack it. Shogakukan’s Kotowaza o shiru jiten states the reverse side plainly. Turned over, it says, the proverb means that the people who talk big and push the weak around are the ones without much ability.
That same dictionary solves the puzzle of the hawk. To hide the talons, it explains, does not mean keeping them out of sight. It means not raising them to threaten. The talons stay where they are. What the hawk holds back is the gesture.
Where it comes from
The image comes from falconry. The Kotowaza o shiru jiten notes that hawking had long been a favourite pursuit of the court nobility and the warrior houses. In the proverbs those classes left behind, the hawk is a bird of rank as well as a hunter. Its companion saying, 鷹は飢えても穂を摘まず, says that the hawk does not peck at grain even when it is starving. The bird in these sayings has a code. It hunts, and it will not stoop to pecking.
The Nihon kokugo daijiten gives the earliest citation as a proverb collection known as the 北条氏直時代諺留, dated to around 1599. Its title ties it to the time of Hōjō Ujinao, the last head of the Hōjō house of Odawara. The same entry records the cat variant, 能ある猫は爪を隠す, and the Daijisen lists 上手の猫が爪を隠す, the skilful cat, among its related sayings. So the two animals ran side by side. The cat version is the more literal one, since a cat really does hide its claws. The hawk version is the more demanding one. The cat has to do nothing at all, while the hawk has to choose not to.
How it gets used today
The Kotowaza o shiru jiten illustrates the saying with a scene from Nakazato Kaizan’s huge serial novel Daibosatsu tōge, published between 1913 and 1941. Someone asks whether old Dr. Dōan really knows jūjutsu. The answer is the proverb: that is just it, the hawk hides its talons. The doctor may sit there feigning ignorance and drunk, but he has all eighteen martial arts folded away in his chest. The example sentence shows the proverb in its natural place, said by an onlooker about somebody else, admiringly, and a little in awe of what may be under the surface.
Outside that example the evidence is mostly in the dictionaries. The Daijisen files the hawk beside a run of Chinese maxims in Japanese reading: great wisdom looks like folly, great skill looks clumsy. The misspelling note points to everyday use. Beyond that, how the phrase sounds in a modern office or classroom can only be inferred. It is the kind of thing said of a quiet colleague whose talent comes out late, and it fits the situation that the dictionary’s reverse side describes, where the loud one turns out to be the one who could not.
Cousins from other tongues
Mandarin approaches the claim from the other end. 半瓶醋, bàn píng cù, “half a bottle of vinegar,” names the person who knows a little and shows all of it. In the zdic gloss it means someone with only a smattering of a skill. A folk formula carries the physics, 一瓶子不满，半瓶子晃荡: the full bottle is silent and the half bottle sloshes. Nobody in this image is hiding anything. The bottle does not decide to slosh, and the full bottle does not decide to keep still. The Japanese hawk needs a will. The Chinese bottle only needs a level of liquid. Where the hawk is praised for restraint, the bottle is simply exposed by its contents.
The Classical Chinese 良賈深藏若虛, liáng gǔ shēn cáng ruò xū, “the good merchant stores deep and looks empty,” moves the hidden thing out of the body and into a storeroom. In the Shiji, Sima Qian has Confucius travel to Zhou to ask Laozi about ritual. Laozi quotes the merchant as something he has heard, adds that the gentleman of full virtue looks like a fool, and then tells the young man what to do about it: put away your proud air and your many desires, your airs and your ambitions. The hawk proverb praises a quality from the outside. This one is handed directly to a gifted man as advice, and the hidden thing is goods, which can be stolen, taxed or envied. Confucius goes away and tells his students he has met a dragon, a creature whose powers he cannot even estimate. The man who told him to look empty is the one he could not measure.
The Latin altissima flumina minimo sono labi, “the deepest rivers flow with the least sound,” comes with its opposite attached. Curtius Rufus sets it at a banquet in Bactria, where Bessus, proud of a kingdom won by crime, is drinking and talking about defeating Alexander across the dinner table. Gobares, a Mede, asks permission to speak and quotes what the Bactrians commonly said: the timid dog barks louder than it bites, and the deepest rivers flow with the least sound. Curtius adds that he put the saying in to show what good sense could exist among barbarians. Here the claim is aimed at the loud man, about the quiet one. Then Gobares gives his advice: the swiftest of kings is already standing in the vestibule of your palace. Bessus draws his sword and has to be held back by his friends, and Gobares slips away in the uproar and goes over to Alexander. Of all the versions this is the only one in which the quiet strength is the enemy, and the man who points it out has to run.
Why it matters
The Japanese version is the only one in this company that makes the holding back a matter of choice. Everywhere else the strength is hidden by its nature, or by the fear of losing it. The hawk is asked for something harder, which is to be a hunter that is able to strike and keeps the gesture back.
That may be why the dictionaries put the hawk at the headword and leave the cat as a variant. A cat that sheathes its claws is just being a cat. A hawk on the glove has its talons in plain view, and what the proverb praises is everything it is not doing with them.