Kosko, Bart: "Fuzzy Thinking". Hyperion, 1993.
A great book, starting from a philosophical point of view and going into all the different
sciences.
Kosko, Bart: "Heaven in a Chip". Three Rivers Press, 1999.
How would our world look if fuzzy thinking was more spread in our daily life. Not so easy to
read, but it gives you a lot to think about. The mathematical parts are in the back of the
book and are not important to understand his ideas.
Mukaidono, Masao: "Fuzzy Logic for Beginners". Singapore: World Scientific, 2001.
The title speaks for itself. A good start, but not very exciting.