That reminds me of a similar story about double positives that I can never remember the details of. Fortunately wikipedia came to the rescue:
"During a lecture the Oxford linguistic philosopher J. L. Austin made the claim that although a double negative in English implies a positive meaning, there is no language in which a double positive implies a negative. To which Morgenbesser responded in a dismissive tone, "Yeah, yeah." [1]
"During a lecture the Oxford linguistic philosopher J. L. Austin made the claim that although a double negative in English implies a positive meaning, there is no language in which a double positive implies a negative. To which Morgenbesser responded in a dismissive tone, "Yeah, yeah." [1]
[1] http://en.wikipedia.org/wiki/Sidney_Morgenbesser