Having analyzed these features, he believed that he was able to characterize, at least partly, the properties of innate grammar.<ref name="Bickerton1983">{{Harvcoltxt|Bickerton|1983|p=122}}</ref> Bickerton inIn his LBH, Bickerton defined very precisely what he considers to be a creole: a language that has arisen out of a prior pidgin that had not existed for more than a generation and among a population where, at most, 20% were speakers of the dominant language and where the remaining 80% were linguistically diverse.{{Citation needed|date=February 2008}} Such a definition excludes many languages that might be called creoles.{{Citation needed|date=February 2008}} Moreover, lack of historical data makes it often impossible to evaluate such claims. In addition, many of the creole languages that fit this definition do not display all the twelve features,{{Citation needed|date=February 2008}} while, according to {{Harvcoltxt|Mühlhäusler|1986}}, the left-out creoles often display more of them. Another problem, raised by {{Harvcoltxt|Mufwene|1986}}, is that if the same bioprogram was the starting point of all creoles, one must explain the differences between them, and language diversity in general, as the bioprogram is universal.
On the other hand, Bickerton, puts emphasis on children's contribution to the development of a creole and the abrupt character of this process. For example, in {{Harvcoltxt|Bickerton|1983}}, he exhibits ungrammatical utterances made by English-speaking children between the ages of two and four, and argues that they are very similar to perfectly grammatical sentences of [[English-based creole languages]]:
