''Fuzzy logic'' is a way to program computers so that they can mimic the imprecise way that humans make decisions. This technology allows for many innovative applications, including cars that virtually drive themselves, washing machines that pick the right wash cycles and water temperature automatically and air conditioning and heaters that adjust to the number of people in the room. This book traces the dramatic story of Lotfi Zadeh, an Iranian-American professor at Berkeley who began developing fuzzy logic more than 27 years ago, and his struggle and subsequent failure to sell his idea to the American academic and business communities.