|Title:||Reviewer's Response to Lightfoot|
|Description:||Response to the 26-Mar-2007 posting by David Lightfoot giving his response
to my review of his book: How New Languages Emerge.
David Lightfoot starts his response to my review with three falsehoods –
that I wanted him to write a textbook on historical linguistics (actually,
his sampling of historical linguistics, while limited, was one of the best
things about his book), that I have not written on language acquisition,
and that I did not understand the most central notions.
Let me address 5 points in his response and invite readers to judge my
review apart from Lightfoot’s strictures.
1. Lightfoot states: “[Arbib] writes that children construct an I-language
that approximates the ambient E-language, but that is inconceivable:
E-language is a different kind of thing from I-languages. For example,
I-languages have structures but E-language is a collection of utterances.”
I had assumed readers would understand the sense of approximation used: an
I-language approximates an E-language if the utterances it produces are far
more likely than not to belong to the E-language, with the approximation
continually tested as the child hears and produces new utterances.
2. Lightfoot says that Pullum & Scholz (2002) do not address his arguments,
which they “characterize accurately as 'not so much stimulus poverty as
stimulus absence' (pp.14-16).” However, I do not read Pullum & Scholz as
endorsing his arguments.
3. Lightfoot states: “[Arbib] says that 'no theory is offered of how the
child activates ''cues'' from the observed E-language,' ignoring discussion
of the expression of cues.” However, I did note that his theory seems to
offer positive features missing in other Universal Grammar-based models of
language acquisition, while suggesting that these features weaken the case
that Universal Grammar is needed to make language-learning possible.
4. Lightfoot notes that I write: “[Lightfoot’s] method is to simply observe
that a change occurs in the texts from date x to date y and then state
without evidence that change in children's I-languages must have been the
driving factor.” Here’s an excerpt from his response: “[M]odal verbs in
English came to be categorized as Inflectional elements in Early Modern
English; several phenomena changed, which can be construed as a function of
[a] single change in I-languages. Thomas More was the last known speaker
with the old system and all the relevant phenomena occur in his extensive
writings. Others had the new system before More's time. In general,
speakers either had the old system or the new system or, for a transitional
period, both systems, but the phenomena cluster systematically and not
randomly.” Absolutely no evidence is cited to support Lightfoot’s claim
that “Hence [sic] the interplay between adult changes and changes in
acquisition by young children, and the complementarity of adult and child
5. Lightfoot regrets that he “was not clear enough for [me] to understand
the central notions of the book [he] wrote.” On the contrary, I commend him
on his clarity.
Pullum, G. K. & B. C. Scholz 2002 Empirical assessment of stimulus poverty
arguments. The Linguistic Review 19:9-50.
|Linguistic Field(s):||Historical Linguistics|