"Butterworth's translations, perhaps to an even greater extent than the scholarly translations of the Medieval Academy, are literal and faithful to the original … both readable and precise … Butterworth's valuable contribution of text, translation, and interpretation will be of interest to even the nonmedievalist." — The Review of Metaphysics"Professor Butterworth makes available to scholars a highly readable text. The English translation combines readable and intelligible English with fidelity to the original Arabic. He gives us an exhaustive analysis of the text and meticulously describes all relevant points related to it. Making excellent use of all available sources in Arabic, Hebrew, Latin, French, German, and English, [he] assiduously confirms the authenticity of the treatises and describes the formal characteristics of the two manuscripts. A glossary of technical terms adds to the contribution. This kind of work attests to a rare quality of scholarship and to Dr. Butterworth's competence and dedication … This is a valuable contribution to Islamic scholarship … A fine piece of work." — The Middle East Journal