  A universal logic, in the intended sense, is one which is applicable in every situation whether realised or not, possible or not. Thus a universal logic is like a universal key, which opens, if rightly operated, all locks. It provides a canon for reasoning in every situation, including illogical, inconsistent and paradoxical ones. Few prevailing logics stand up to such a test. … [A] universal logic should be adequate for mathematical and philosophical purposes—and also for logical functions in other areas such as biology, economics, astrology, theology, and so on (893).