ABSTRACT
This chapter discusses two parts, the first of which consisted of an examination of the attempt to derive an alleged example of non-formal logic from linguistic rules, the second of an examination of the attempt to make good a parallel claim in respect of a law of formal logic. In putting forward an alternative theory of the basis of logic, it starts by reconsidering the same formal logical law—the law of non-contradiction. Information on propositional logic; predicative logic; things and attributes; logic of relations and alternative logics is provided. The function of negation, it has been argued, is a necessary constituent of all determinate thought; and any language that is capable of expressing propositions, true or false, must be equipped to express this function of exclusion as well as that of affirmation. At the same time, all thought, to be determinate, must conform to the law of non-contradiction.
