It is the Master's answer in the Analects to a clever question: asked which of two men is the better, the one who overshoots or the one who falls short, and expected to say the overshooter, Confucius answers that to go beyond is as wrong as to fall short. The line is balanced on purpose, and the balance is what the words carry; as a Japanese proverb it mostly scolds excess, the fault people see more of, so a person who chooses it may mean the rebuke to too much or the whole even measure. The English title is Arthur Waley's sentence.
The four characters close an exchange in the Analects in which a disciple, Zigong, asks Confucius to rank two of his students; the line is the Master's own answer, refusing to call either fault worse than the other.
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