Scientific metaphors going public

Studies of scientific metaphors have largely focused on the existence, application, and function of metaphors in specialist scientific discourse, in some way overlooking the use of scientific metaphors in non-specialist discourses, in particular that of popularization. Richard Boyd (Boyd, Richard, 1993. Metaphor and theory change: what is "metaphor" a metaphor for? In: Ortony, Andrew (Ed.), Metaphor and Thought. Cambridge University Press, Cambridge, pp. 481-533) is an exception, however. He suggests the existence of two fundamentally separated categories of scientific metaphors: theory-constructive and pedagogical/exegetical metaphors. Whereas the theory-constructive metaphors represent original scientific thought and terminology, pedagogical metaphors merely describe or explain existing knowledge. The aim of this paper is to discuss the relationship between these two categories of metaphors from a pragmatic and empirical perspective. The analysis is based on a case study of the application of metaphors describing the genetic code and protein synthesis in three specialist and three non-specialist scientific articles. The study reveals that, depending on context and genre, exactly the same metaphors are used for theory-constructive and for pedagogical purposes. Consequently, metaphors should not be classified according to the individual expressions, but in relation to the developmental history of the specific metaphor, as well as such parameters or criteria as communicative purpose and genre.