Full Idea
Any borderline case must be under our control, in the sense that it can be settled by making the predicates more precise.
Gist of Idea
Borderline cases must be under our control, as capable of greater precision
Source
Kit Fine (Vagueness, Truth and Logic [1975], 3)
Book Reference
'Vagueness: a Reader', ed/tr. Keefe,R /Smith,P [MIT 1999], p.134
A Reaction
Sounds good. Consider an abstract concept like the equator. It is precise on a map of the world, but vague when you are in the middle of the tropics. But we can always form a committee to draw a (widish) line on the ground delineating it.