COMPLEX PROPOSITIONS AND COMPOUND PROPOSITIONS

Besides predicative sentences there are complex sentences such as the compound sentences of propositional logic, which have sentences as components, the quantified sentences of predicate logic, and other sentences, such as existence sentences and identity sentences. These sentences differ in form. There are also sentences that are necessarily true, such as sentences about determinate exclusion, that a plane figure cannot be square and circular, for example, as well as the familiar theorems of formal logic. These sentences differ in status from those previously mentioned. I have spoken here about sentences, because it is easier in most of these cases to talk about sentences, although I still maintain that propositions are the primary truth bearers. In the second chapter a defence was offered of the thesis that the predicate ‘true’ should mean the same thing for all the different kinds of sentence and proposition that it applies to. Truth is a property of a sentence or proposition that is determined by the facts, or by how things are, for which the truth of predicative sentences and propositions, consisting in simple correspondence, is the paradigm case and, indeed, the foundational case. And the way in which the facts, or how things are, determine the truth of truth-functional sentences is a paradigmatic case of the extension of the notion of truth to non-predicative sentences.