Curiosity killed the cat

This expression means that inquisitiveness can often have dangerous consequences. The expression was originally ‘care killed the cat’ when the word ‘care’, dating back to the 1400s meant over-concern. Ben Jonson is the first known reference Every Man and His Humour (1598) “Hang sorrow, care’ll kill a cat” but he may not have coined it because at about the same time Shakespeare also used it in Much Ado About Nothing Act V, Scene I. “Though care killed a cat, thou hast mettle enough in thee to kill care.” The way Shakespeare uses it implies that it was a well-known saying. Curiosity did not replace care in the saying until the late 19th century when it seemed more apt than the old meaning of care, which had fallen into disuse.