In Metaphysics IV.2 Aristotle assigns a very specific role to dialectic in philosophical and scientific inquiry. This role consists of the use of the special form of dialectic which he calls peirastic. This is not a new conception of, or a new role for, dialectic in philosophy and science, but one also assigned to it in the Topics and Sophistical Refutations. In the SE Aristotle lays down multiple overlapping requirements for the premises or bases for peirastic dialectical argument. These must be (1) things known by skilled practitioners of dialectic; (2) things in fact in accord with the science or subject of the peirastic dialectical encounter in question; (3) things known by non-experts as well as by experts in that subject, (4) things known even by ordinary people in general; (5) things believed by the answerer in the given peirastic encounter and (6) things which are as noted and accredited (endoxa) as possible. We can see from Aristotle’s discussion and from his, and earlier, examples that all of these various requirements can be and are met by a single identifiable set of propositions, one whose use gives a special power to peirastic, one adequate to show the falsity of particular pretensions to knowledge on specific points, in science and philosophy.