An introduction to the life and philosophy of Abul-Barakat al-Baghdadi -- The theory of existence -- Abul-Barakat's critique of Aristotle: the transformation and alteration of being to existence -- The theory of the existent conceived on the basis of innate principles -- Abul-Barakat's philosophy of science and the principles of physics -- Epistemological ascertainment of psychology -- The logical theories of reference, predication and accidents