 Each of these passages explicitly describes the study of animals with which Aristotle is engaged in the language of Aristotle’s theory of research in APo. II 1. Indeed, the passage from HA I 6 does so by insisting that the natural method to use is to first get clear on the differences and attributes to be demonstrated (‘establish the fact that…’) before going on to find the causes (‘the reason why, i.e. the cause’) to be appealed to in these demonstrations. Animal inquiries (historiai) are a kind of hoti inquiry—that is, the History of Animals presents the facts to be explained, organized so as to be prepared for causal  demonstration.[7]