What is Yes I Can't?
1.
Is a positive answer to a negative question
taking simply mathematical principals, two positives make a positive, two negatives makes a positive, so a negative combined with a positive leaves a negative.
so a question like, "can't you fix that computer?" requires the response, "Yes I can't" if indeed, you cannot do so, but "no, I can" if you are able to.
simple really
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2.
The request for something, but usually ends up in a bizzare response from one's perspective.
Can I go to the mall?
Response: Yes you can't
Can you go to the party this weekend?
Response: Yes I can't
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