A figure of speech in which an expression is used to refer to something that it does not literally denote as a means of suggesting a similarity. Metaphors, like analogies, play important roles in the development of scientific theories and in applying theory to a set of metaphorical re-description. It has been argued that when science enters a revolutionary phase that it involves metaphorical re-description. Such was the case, for example, when Piaget’s genetic epistemology became more popular at the expense of behavioristic theories applied to the study of child development. For its proper application, a metaphor is more structured in its application than an analogy in that it requires a source model or tenor, a target model or vehicle and a ground (the semantic basis for comparison). For example, in attempting to gain further insights in to the nature of ontogenetic development, metamorphosis might be the source model and non-metamorphic development the target model, with qualitative change acting as the ground.
See Analogy, Developmental bootstap, Folk wisdom, Grammatical metaphor, Heuristic, Homology, Hydraulics, Id, Isomorphism, Metamorphosis, Metonymy, Mind-body problem, Operationalism, Simile, Synecdoche, Trope