This paper aims to critique Robert Bley-Vroman's views on accessibility to UG. In paper "what is the logical problem of foreign language learning?" Robert Bley-Vroman puts forward the famous fundamental difference hypothesis. Robert Bley-Vroman thinks that child first language learning is quite different from adult foreign language learning. In this paper author's view is different from Robert Bley-Vroman's. Author thinks the innate system that guides child acquisition also operates in adult foreign language learning.