Syntactic Theory and First Language Acquisition: Cross-linguistic Perspectives -- Volume 1: Heads, Projections, and Learnability -- Volume 2: Binding, Dependencies, and Learnability : Psychology Press : 9780805813517 : 0805813519 : 13 Dec 1994 : Universal Grammar (UG) is a theory of both the fundamental principles for all possible languages and the language faculty in the "initial state" of the human organism. These two volumes approach the study of UG by joint, tightly linked studies of both linguistic theory and human competence for language acquisition. In particular, the volumes collect comparable studies across a number of different languages, carefully analyzed by a wide range of international scholars. The issues surrounding cross-linguistic variation in "Heads, Projections, and Learnability" (Volume 1) and in "Binding, Dependencies, and Learnability" (Volume 2) are arguably the most fundamental in UG. How can principles of grammar be learned by general learning theory? What is