By Howard Lasnik, Juan Uriagereka
Positive data involving auxiliary fronting are never evidence for a constraint such as the structure-dependent hypothesis. At best, positive data of any complexity are direct evidence for a simple-minded hypothesis, of the sort of ‘front the first auxiliary (after something or other)’. On the widespread assumption that negative data are generally unavailable to children learning language, a serious empiricist alternative to the rationalist view that linguistic structure is partly innate would have to show how the correct hypothesis (‘front the matrix auxiliary’) is induced from mere extensions from positive data. But this does not seem possible.