 A is also called the major term, C the minor term. Each figure can further be classified according to whether or not both premises are universal. Aristotle went systematically through the fifty-eight possible premise combinations and showed that fourteen have a conclusion following of necessity from them, i.e. are syllogisms. His procedure was this: He assumed that the syllogisms of the first figure are complete and not in need of proof, since they are evident. By contrast, the syllogisms of the second and third figures are incomplete and in need of proof. He proves them by reducing them to syllogisms of the first figure and thereby ‘completing’ them. For this he makes use of three methods: