Full Idea
The three components of essentialism as a folk belief are the idea that certain categories are natural kinds, the idea that some unobservable property causes the way things are, and the idea that words reflect real structures.
Gist of Idea
Folk essentialism rests on belief in natural kinds, in hidden properties, and on words indicating structures
Source
Susan A. Gelman (The Essential Child [2003], 01 'Prelims')
Book Reference
Gelman,Susan A.: 'The Essential Child' [OUP 2005], p.7