Before selecting the most significant passage for rhetorical theory in the work of I. A. Richards, two prerequisites seem necessary. First is a criterion or standard upon which to base a selection. The title itself (which was assigned), suggests the criterion of impact: a passage from Richards that has proven so important that it must be included in any serious discussion of rhetorical theory. Upon that basis, the passage chosen for this essay is found in The Philosophy of Rhetoric. In Chapter V, Richards writes, is the omnipresent principle of language. (1) There are to be sure other passages on metaphor that could have been chosen. This one, however, was selected because its insistence upon the ubiquity of metaphor in language necessitates using other Richardian statements about metaphor in order to make a full explanation about its importance.