  The previous objections to the Unlearning Problem Argument made the  points, first, that negative evidence does exist in the pld  (in the form of regularities both in others' language use and in how  others react to children's own productions), and second, that  children (and other animals) seem very good at exploiting this kind  of information for the purposes of learning about their world. This  would seem to be rather a good thing, given that there is reason to  think that learners must be able to learn in domains where  explicit negative data do not exist, and in the absence of  specialized innate knowledge of those domains. For the unlearning  problem is a problem for learning from experience quite generally.  That is, there are many domains in which learners lack explicit  evidence as to what things are not: trees are not cars,  Irish stews are not curries, birds are not fish and MacDonald's is  not a branch of the CIA. No-one ever told you any of these things,  but it's crazy to think that you now know them because you possess  analogs to the ‘Language Acquisition Device’ for each of  these domains. Clearly, in at least some areas, people are able to  learn an awful lot on the basis of largely positive data, and while  this of course does nothing to show that language is one of those  areas, it does indicate that the Unlearning problem argument by  itself is no argument for linguistic nativism at all, let alone for  the Chomskyan (UG-based) version of that position.