ABSTRACT

In this chapter, the author develops a deductive system for natural language, which is meant to be comparable in its deductive power to first order predicate calculus. He also develops the system for only some of the sentences of natural language, and for only some of the logical relations between these sentences. The author relies on knowledge and understanding of English in determining, firstly, which sentences are grammatically correct; secondly, which sentences are propositional combinations of predications of the kind to be discussed; and lastly, in transforming sentences from active to passive, from singular to plural, etc. The fact that he ignores these language specific features makes it impossible to apply his derivation rules mechanically to any specific language. The author specifies the rules for the introduction of premises, for the use of theorems of the propositional calculus, and for the use of other derivation rules of natural language that do not involve quantification.