The complexity of trees, universal grammar and economy conditions

Abstract

In this squib, I argue that the child faces a severe computational complexity problem in parsing even the simplest of trees: the number of possible trees consistent with UG grows exponentially as a function of the number of lexical items. Economy conditions have the result of drastically decreasing the complexity of the parsing task. I also discuss the relationship between UG, I-language, economy conditions and explanatory adequacy.