At sixes and sevens

"At sixes and sevens" is an English idiom used to describe a condition of confusion or disarray.

The phrase probably derives from a complicated dice game called "hazard". It is thought that the expression was originally "cinque and sice" (from the French numerals for five and six). These were considered to be the riskiest numbers to shoot for (to "set on"), and those who tried for them were considered careless or confused.

A similar phrase, "to set the world on six and seven", is used by Geoffrey Chaucer in his Troilus and Criseyde. It dates from the mid-1380s and seems from its context to mean "to hazard the world" or "to risk one's life".William Shakespeare uses a similar phrase in Richard II, "But time will not permit: all is uneven, And every thing is left at six and seven".

The phrase is also used in Gilbert & Sullivan's comic opera H.M.S. Pinafore (1878), where Captain Corcoran, the ship's Commander, is confused as to what choices to make in his life, and exclaims in the opening song of Act II, "Fair moon, to thee I sing, bright regent of the heavens, say, why is everything either at sixes or at sevens?"

It is possible that an ancient dispute between the Merchant Taylors and Skinners livery companies may have helped to popularise the phrase. The two trade associations, founded in the same year, argued over sixth place in the order of precedence. In 1484, after more than a century of bickering, the Lord Mayor of London Sir Robert Billesden decided that at the feast of Corpus Christi, the companies would swap between sixth and seventh place and feast in each other's halls. Nowadays, they alternate in precedence on an annual basis.

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