he adduced to establish figurative usage—namely, his statement, “If these expressions are literal, they must be homonymous”—rests on two premises: first, that homonymy necessarily follows; and second, that it is invalid. This argument is weak, for the first premise may be challenged, the second may be challenged, or both may be challenged together.
His assertion that “homonymy necessarily follows” holds only if he is granted that, within a single language and under a single linguistic convention, there are expressions denoting disparate meanings with no shared element. This is a matter of well-known dispute. Even if it is conceded, those who accept homonymy agree that language contains expressions whose meanings have both a shared element and a distinguishing element. This occurs sometimes with identical word forms and sometimes with different ones. Just as a single expression may have multiple meanings, multiple expressions may have a single meaning, as in the case of synonyms.
Although some people deny absolute synonymy, the point is that two expressions may agree in denoting a meaning, while one conveys something additional. For example, a sword may be called sayf (sword), sārim (cutter), and muhannad (Indian blade). The word sayf denotes it without qualification; sārim originally denotes its quality of cutting; and muhannad denotes its association with India. Nevertheless, usage is known to shift terms from adjectival to nominal status, so that this term comes to be applied to