Fuzzy logic would seem to be wrong because it contradicts fundamental principles in nature:
A thing can be either small or tall. A bird can either fly or not. If the bird is in the air, it is flying, and if he is on the ground, then it is walking. This kind of distinction is natural.
What Fuzzy logic is trying to imagine is the opposite. It doesn't seem to make sense to use fuzzy logic to explain phenomena in the natural world.
A possible argument against Fuzzy logic is to show that it wasn't invented as a mathematical theory but as a non-scientific concept. Quote:
“Fuzzy set theory [...] has its roots in the social nature of human understanding. Fuzzy sets approach directly relates to practical applications of [...] creative misunderstanding” Dimitrov, Vladimir. "Fuzzy logic in service to a better world: The social dimensions of fuzzy sets." IMAC/IEEE CSCC’90 conference, Athens,(Greece). 1999. pdf
So the papers says basically, that Fuzzy logic is the opposite of a mathematical understanding of a world. Are more examples available which disprove Fuzzy logic?