Theoretical essay on the nature of language universals. B. argues that language universals should be seen as biologically based, resulting from a kind of innate bioprogram for language (comparable to the innate bioprogram which ensures our physical development from child to adult). Evidence for this claim is found in Creole languages, L1-acquisition, language origins, sign language, and linguistic change. Furthermore, the consequences of the existence of such a bioprogram for L2-acquisition are discussed.