Full Idea
There are vague and imperfect essences, as in the question of how few hairs a man can have without being bald.
Gist of Idea
The essence of baldness is vague and imperfect
Source
Gottfried Leibniz (New Essays on Human Understanding [1704], 3.05)
Book Reference
Leibniz,Gottfried: 'New Essays on Human Understanding', ed/tr. Remnant/Bennett [CUP 1996], p.302
A Reaction
This example is much discussed in contemporary debate, but I now learn that it has a venerable history. The surprise here is the word 'essences', because I had taken Leibnizian essences to be 'perfect ideas', and hence precise.