But Aristotle is not satisfied to describe metaphysics as the investigation of first causes. He also tells us that it is the science that studies being qua being. As this characterization gets fleshed out, metaphysics turns out to be not another departmental discipline with a special subject matter of its own. It is rather a universal science, one that considers all the objects that there are. On this characterization, then, metaphysics examines the items that constitute the subject matter for the other sciences. What is distinctive about metaphysics is the way in which it examines those objects; it examines them from a particular perspective, from the perspective of their being beings or things that exist. So metaphysics considers things as beings or as existents and attempts to specify the properties or features they exhibit just insofar as they are beings or existents. Accordingly, it seeks to understand not merely the concept of being, but also very general concepts like unity or identity, difference, similarity, and dissimilarity that apply to everything that there is. And central to metaphysics understood as a universal science is the delineation of what Aristotle calls categories. These are the highest or most general kinds under which things fall. What the metaphysician is supposed to do is to identify those highest kinds, to specify the features peculiar to each category, and to identify the relations that tie the different categories together; and by doing this, the metaphysician supposedly provides us with a map of the structure of all that there is. 引自 Introduction
只要来一个所谓的“先验还原”，这个being qua being不就是现象学么，怪不得Dan Zahavi说"eventually I got interested in Husserl, which I back then took to be an interesting synthesis of Aristotle and Kant."
"considers all the objects there are""universal science" 胡塞尔不也是继承了这个“科学之科学”的取向么？区别在哪里？