Of the Proposition as distinguished from Other Sentences.
§ 172. As in considering the term, we found occasion to distinguish it from words generally, so now, in considering the proposition, it will be well to begin by distinguishing it from other sentences.
§ 173. Every proposition is a sentence, but every sentence is not a proposition.
§ 174. The field of logic is far from being conterminous with that of language. Language is the mirror of man's whole nature, whereas logic deals with language only so far as it gives clothing to the products of thought in the narrow sense which we have assigned to that term. Language has materials of every sort lying strewn about, among which the logician has to seek for his proper implements.
§ 175. Sentences may be employed for a variety of purposes—
(1) To ask a question;
(2) To give an order;
(3) To express a feeling;
(4) To make a statement.
These various uses give rise respectively to