Full Idea
It is clear the nominal essences really are the properties of the things which have them: they are (a subset of) the observable properties of the things.
Gist of Idea
Nominal essence are the observable properties of things
Source
Antony Eagle (Locke on Essences and Kinds [2005], IV)
A Reaction
I think this is wrong. The surface characteristics are all that is available to us, so our classifications must be based on those, but it is on the ideas of them, not their intrinsic natures. That is empiricsm! What makes the properties 'essential'?
Related Idea
Idea 15644 In nominal essence, Locke confuses the set of properties with the abstracted idea of them [Eagle on Locke]