This book exclusively surveys the active on-going research of the current maturity of fuzzy logic over the last four decades. Many world leaders of fuzzy logic have enthusiastically contributed their best research results into five theoretical, philosophical and fundamental sub areas and nine distinctive applications, including two PhD dissertations from two world class universities dealing with cutting-edge research areas of bioinformatics and geological science. Beyond the scope of survey and collection of the book, one important spin off is the emerging and recognition of a major scientific paradigm shift from the conventional mathematics to the mathematics of uncertainty, which arguably holds the key to solving very difficult and complex problems in biological and social sciences alike. The book, loaded with historical perspective, creative thinking, critical reviewing, and uniquely constructed strategy for future growth of this dynamic research area, is an invaluable resource for active researchers at all levels, university administrators, foundation directors, funding agency program chiefs, research & development planners and technological assessors.