Extracting fuzzy rules from data allows relationships in the data to be modeled by "if-then" rules that are easy to understand, verify, and extend.

fuzzy rules for both function approximation and pattern classification. The rule extraction methods are based on estimating clusters in the

data; each cluster obtained corresponds to a fuzzy rule that relates a region in the input space to an output region

Source:

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.476.6800&rep=rep1&type=pdf