  The bioprogram hypothesis claims that creolization occurs as a result of the action of the language faculty: children who learn language  from degraded (e.g., pidgin) inputs are compelled by their innate  knowledge of grammar to produce a fully-fledged natural language (the creole) as output. As an example of how children add UG-constrained  structure to languages learned from degraded inputs, Pinker cites the case of Simon, a deaf child studied by Newport and her colleagues,  who learned American Sign Language (ASL) from parents who themselves  were not exposed to ASL until their late teens. Although they used  ASL as their primary language, Simon's parents were “in many  ways…like pidgin speakers,” says Pinker (1994:38). For  instance, they used inflectional markers in an inconsistent way and  often failed to respect the structure-dependence of the rules  governing topicalization in that   language.[27]  But “astoundingly,” says Pinker, “though Simon saw  no ASL but his parents' defective version, his own signing was far  better ASL then theirs…Simon must somehow have shut out his  parents' ungrammatical ‘noise.’ He must have latched on  to the inflections that his parents used inconsistently, and  interpreted them as mandatory.” (1994:39) Pinker views this as  a case of “creolization by a single living child”  (ibid.) and explains Simon's conformity to ASL grammar in  terms of the operation of his innate language faculty during the  acquisition period.