 Another kind of Emergentist, like Tomasello (2003), will stress the role of theory of mind and the capacity to use symbols to change conspecifics’ mental states as uniquely human preadaptations for language acquisition, use, and invention. MacWhinney (2005) aims to explain linguistic phenomena (such as phrase structure and constraints on long distance dependencies) in terms of the way conversation facilitates accurate information-tracking and perspective-switching.