less
bears the heaviest stress in both versions. Despite the apparent contradiction, either reading of this—both the affirmative and negative—usually have the same meaning. The exception would be in a sentence where thecould
[m2]bears the heaviest stress: I COULDcare less, [but I don't.]
.) •Tom: The rain is coming! The carpet will get wet! Mary: I couldn't care less.
•Bill: I'm going to go in there and tell off the boss? John: I could care less.