The Poverty of Stimulus (hereafter, “POS”) argument is used in a number of fields
of cognitive science, nature/nurture debates, moral psychology, developmental
psychology and biology. In particular, cognitive linguists (Berwick et al.;
Chomsky; Clark and Lappin; Cowie; Crain; Lightfoot; Pullum and Scholtz) use
the POS argument to support “linguistic nativism,” the view that humans have
innate knowledge of certain linguistic features such as rules of syntax that are
universal across every natural language.
The POS argument starts with an observation that children have “knowledge
of language”—a host of implicit “knowledge” and automatic cognitive abilities—
and an ability to understand, interpret, and produce language. If children acquired
knowledge of language via a general learning mechanism (i.e., pattern recognition
faculties that are not specific to language) then the environment must contain a rich
source of primary linguistic data (e.g., spoken, written, or signed tokens of
languages) from which to extract information about the rules of grammar.
However, there is a poverty of linguistic data and children’s knowledge of
language far exceeds the set of stimuli the environment provides. Thus, children
must be innately endowed with some linguistic knowledge that allows them to
compensate for missing linguistic data from the environment (see Cowie for
discussion).
