 Consider, briefly, the case of Aristotle’s Metaphysics. Here Aristotle is seeking wisdom. Part of the argument of the Metaphysics is in an attempt to clarify what sort of wisdom Aristotle is seeking. Suffice it to say that Aristotle conceives of this wisdom as a science of substance that is, or is a part of, a science of being qua being (for further information about this argument, see the entry Aristotle’s Metaphysics, especially Sections 1 and 3.) What is important is that this science consists in a causal investigation, that is, a search for the relevant causes. This helps us to understand why the most general presentation of Aristotle’s theory of causality is repeated, in almost the same words, in Physics II 3 and in Metaphysics V 2. Although the Physics and the Metaphysics belong to two different theoretical enterprises, in both cases we are expected to embark on an investigation that will eventuate in causal knowledge, and this is not possible without a firm grasp of the interrelations between the four (types of) causes.