Full Idea
Real essences are objectively real, they concern being, they are knowable, they are definable, and they are classifiable.
Gist of Idea
Essences are real, about being, knowable, definable and classifiable
Source
report of David S. Oderberg (Real Essentialism [2007], 1.4) by PG - Db (ideas)
Book Reference
Oderberg,David S.: 'Real Essentialism' [Routledge 2009], p.18
A Reaction
This is a lovely summary (spread over two pages) of what essentialism is all about. It might be added that they are about unity and identity. The fact that they are intrinsically classifiable seems to mislead some people into a confused view.