Chercher midi à quatorze heures. To look for knots in a bulrush; much ado about nothing; to explain prosily what is perfectly obvious.
There is a variant of this locution: Chercher midi où il n'est qu'onze heures, to look for a needle in a bottle of hay; to give oneself a vast lot of trouble for nothing. At one time, hundreds of persons looked for the millennium and end of the world on fixed dates, and to them the proverb would apply.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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