Who is afraid of constructivism?

Both generative and constructivist researchers agree that children are able to form abstractions and produce novel grammatically patterned utterances. Both approaches are able to explain such abilities, and hence their existence does not entail an innate Universal Grammar. However, generativists and constructivists differ in their views on the nature of early generalisations: while generative researchers assume that adult-like linguistic representations are present from the very beginning, constructivists argue that children begin with relatively specific, low level schemas and gradually extract more abstract patterns. There is considerable empirical evidence for the latter position. Moreover, constructivist theories provide a better explanation for principled behaviour not just the observed patterns, but also the absence of certain constructions in children's early productions and various developmental asynchronies.