Abstract: | We propose that in understanding a metaphor, an individual sees a concept from one class or domain in terms of its similarity in two different respects to a concept from another class or domain. The two kinds of similarity are within-domain similarity, or the degree to which two concepts occupy similar positions with respect to their own class or domain; and between-domain similarity, or the degree to which the classes or domains occupied by the concepts are themselves similar. To test this dual notion of similarity, we obtained ratings of the aptness of 64 metaphors from one group of subjects and ratings of their comprehensibility from another group of subjects. The terms of the metaphors had been scaled (based on the ratings of pretest subjects) to give measures of distance both within and between domains. Aptness of metaphors related positively to betweendomain distance, negatively to within-domain distance, and not at all to overall distance. Metaphors are thus perceived as more apt to the extent that their terms occupy similar positions within domains that are not very similar to each other. Comprehensibility also related to aptness. In a second experiment, subjects ranked a set of terms as possible completions for metaphors. For both groups of subjects in this experiment, the rank of an alternative's within-domain distance correlated with its relative popularity. Quantitative models, patterned after a model proposed by D. Rumelhart and A. A. Abrahamson (Cognitive Psychology, 1973, 5, 1–28) for analogical reasoning, afforded significant prediction of the choices of the group of subjects in which all the possible completions of a metaphor were from a single domain. The same models did not predict the choices of a group of subjects in which the possible completions of the metaphors were from different domains. |