Which is correct: I could care less or I couldn't care less?
The expression I could not care less originally meant 'it would be impossible for me to care less than I do because I do not care at all'. It was originally a British saying and came to the US in the 1950s. It is senseless to transform it into the now-common I could care less. If you could care less, that means you care at least a little. The original is quite sarcastic and the other form is clearly nonsense. The inverted form I could care less was coined in the US and is found only here, recorded in print by 1966. The question is, something caused the negative to vanish even while the original form of the expression was still very much in vogue and available for comparison - so what was it? There are other American English expressions that have a similar sarcastic inversion of an apparent sense, such as Tell me about it!, which usually means 'Don't tell me about it, because I know all about it already'. The Yiddish I should be so lucky!, in which the real sense is often 'I have no hope of being so lucky', has a similar stress pattern with the same sarcastic inversion of meaning as does I could care less.