Full Idea
Fuzzy logic is based on a continuum of degrees of truth, but it is committed to the idea that it is half-true that one identical twin is tall and the other twin is not, even though they are the same height.
Gist of Idea
Fuzzy logic uses a continuum of truth, but it implies contradictions
Source
Timothy Williamson (Interview with Baggini and Stangroom [2001], p.154)
Book Reference
Baggini,J/Stangroom,J: 'New British Philosophy' [Routledge 2002], p.154
A Reaction
Maybe to be shocked by a contradiction is missing the point of fuzzy logic? Half full is the same as half empty. The logic does not say the twins are different, because it is half-true that they are both tall, and half-true that they both aren't.