Full Idea
In a slogan, Unger's thesis is that all vague predicates lack application ('nihilism', says Williamson). Classical logic can be retained in its entirety. There are no borderline cases: for vague F, everything is not F; nothing is either F or borderline F.
Gist of Idea
Vague predicates lack application; there are no borderline cases; vague F is not F
Source
report of Peter Unger (There are no ordinary things [1979]) by R Keefe / P Smith - Intro: Theories of Vagueness §1
Book Reference
'Vagueness: a Reader', ed/tr. Keefe,R /Smith,P [MIT 1999], p.13
A Reaction
Vague F could be translated as 'I'm quite tempted to apply F', in which case Unger is right. This would go with Russell's view. Logic and reason need precise concepts. The only strategy with vagueness is to reason hypothetically.