Full Idea
The history of deviant logics is without a single success. Bivalence has been denied at least since Aristotle, yet no anti-bivalent theory has ever left the philosophical nursery.
Gist of Idea
No attempt to deny bivalence has ever been accepted
Source
Roy Sorensen (Vagueness and Contradiction [2001], Intro)
Book Reference
Sorensen,Roy: 'Vagueness and Contradiction' [OUP 2004], p.8
A Reaction
This is part of a claim that nothing in reality is vague - it is just our ignorance of the truth or falsity of some propositions. Personally I don't see why 'Grandad is bald' has to have a determinate truth value.