This is a study of the influence of Aristotle's Posterior Analytics on the structure and methodology of the science of being qua being undertaken in his Metaphysics. Bell argues that Aristotle's account of the science of being developed in the methodological chapters of the Metaphysics is significantly influenced by his conception of scientific knowledge in the Posterior Analytics, in particular that Aristotelian metaphysics is a discipline unified and distinguished from the other sciences by the 'qua itself' relation of its objects to being and substantiality.This discipline undertakes three different tasks: inquiries into the essential attributes of being, the principles and causes of being, and the common axioms. These tasks employ different methodologies, which are all influenced by methodologies developed in the Posterior Analytics. In the latter two cases, however, these methodologies are significantly adapted for new tasks and circumstances.Bell offers an interpretation of the Metaphysics' central books according to which they constitute a contribution to the inquiry into the principles and causes of being, and argues that the problem of the relationship between the science of being and first philosophy or theology is also most usefully addressed within this framework.This book will be interest to scholars and students of Aristotle's metaphysics, logic, and philosophy of science.