Fuzzy boundaries and the extension of object-words

An extensive fuzzy boundary was identified within the adult extension of two exemplary object-words, 'dog' and 'ball'. The fuzzy boundaries were incorporated into the standard of adult extension against which the preschool child's use of 'dog' and 'ball' was compared, and the investigation provided a framework in which children's responses to fuzzy boundary referents could be accommodated. Responses to fuzzy boundary referents were considered as having precedents within adult extension and the data revealed the provision of precedents for a significant number of the young child's applications and non-applications of the words. The investigation concluded that, through adherence to an oversimplified concept of adult extension, previous research has underestimated the degree of correspondence that exists between child and adult extension.