Square peg in a round hole

"Square peg in a round hole" is an idiomatic expression which describes the unusual individualist who could not fit into a niche of his or her society.

The metaphor was originated by Sydney Smith in "On the Conduct of the Understanding", one of a series of lectures on moral philosophy that he delivered at the Royal Institution in 1804–06:

If you choose to represent the various parts in life by holes upon a table, of different shapes,—some circular, some triangular, some square, some oblong,—and the person acting these parts by bits of wood of similar shapes, we shall generally find that the triangular person has got into the square hole, the oblong into the triangular, and a square person has squeezed himself into the round hole. The officer and the office, the doer and the thing done, seldom fit so exactly, that we can say they were almost made for each other.

The Oxford English Dictionary has as its earliest citation Albany Fonblanque, England under Seven Administrations, 1837, "Sir Robert Peel was a smooth round peg, in a sharp-cornered square hole, and Lord Lyndenurst is a rectangular square-cut peg, in a smooth round hole."

The British novelist Edward Bulwer-Lytton published the metaphor in a late 19th-century book:

Kenelm Chillingly asks, "Does it not prove that no man, however wise, is a good judge of his own case? Now, your son's case is really your case —- you see it through the medium of your likings and dislikings, and insist upon forcing a square peg into a round hole, because in a round hole you, being a round peg, feel tight and comfortable. Now I call that irrational."

The farmer responded, "I don't see why my son has any right to fancy himself a square peg ... when his father, and his grandfather, and his great-grandfather, have been round pegs; and it is agin' nature for any creature not to take after its own kind."

This idiomatic expression has proven to be quite durable into the 21st century. It is used in a range of contemporary business-related circumstances; and illustrative examples include:

The idiomatic expression conjures a visual image, and this is evolving independently, e.g.,

Sejong the Great of Korea commented, in 1443, that using Chinese characters for Korean was “like trying to fit a square handle into a round hole”. He subsequently developed the Hangul phonetic alphabet.

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