An argument that children are born to assign structures to their
ambient language, yielding a view of language variation not based on
parameters defined at UG.
In this book, David Lightfoot argues that just as some birds are born to
chirp, humans are born to parse--predisposed to assign linguistic
structures to their ambient external language. This approach to language
acquisition makes two contributions to the development of Minimalist
thinking. First, it minimizes grammatical theory, dispensing with three
major entities: parameters; an evaluation metric for the selection of
grammars; and any independent parsing mechanism. Instead, Lightfoot
argues, children parse their ambient external language using their
internal language. Universal Grammar is "open," consistent with what
children learn through parsing with their internal language system.
Second, this understanding of language acquisition yields a new view of
variable properties in language--properties that occur only in certain
languages. Under the open UG vision, very specific language
particularities arise in response to new parses. Both external and
internal languages play crucial, interacting roles: unstructured,
amorphous external language is parsed and an internal language system
results.
Lightfoot explores case studies that show such innovative parses of
external language in the history of English: development of modal verbs,
loss of verb movement, and nineteenth-century changes in the syntax of
the verb to be. He then discusses how children learn through parsing;
the role of parsing at the syntactic structure's interface with the
externalization system and logical form; language change; and variable
properties seen through the lens of an open UG.
