Constitutive and epistemic functions of rhetoric and metaphor in science: Space-time metaphoric extensions of molecular biology during development of the recombinant DNA controversy

Constitutive and epistemic functions of rhetoric and metaphor in science are explicated through developmental study of change in conceptual metaphors within the discipline and profession of molecular biology prior to and during development of the recombinant DNA controversy of the 1970s. Exemplars of molecular biology discourse from 1944 to 1978 are rhetorically analyzed to reveal underlying conceptual metaphors that have shaped molecular biology's evolving conceptualization of space-time reality, its research programs, and its evolving understanding of recombinant DNA technology and potential biohazards. Changes in molecular biology's conceptualization of reality develop through evolution of conceptual metaphors coherent with and grounded in accepted disciplinary understanding and the scientists' lived world. Scientists' discourse employs the art of rhetorical invention by using the scientific audience's understanding to induce a change in that understanding through metaphoric extensions that "move" the audience into another spatial and/or temporal understanding of reality.;In the recombinant DNA controversy scientists made effective instrumental rhetorical choices which convinced Congress that rapid progress in scientific understanding of potential biohazards made stringent regulations unnecessary. Occasionally scientists acted unethically by their own standards of scientific conduct, but past criticisms of the scientists reflect a failure to consider developmental patterns and understand the scientists' conceptualization system. Complex interrelationships between scientific and public discourse also indicate that the conceptual metaphor of separate "spheres" of discourse is imprudent.;The discipline of molecular biology has been shaped by rhetoric and metaphor, which have constituted and changed conceptualizations of space-time reality and programs for research, and which have focused scientific efforts in pragmatic ways. From Schrodinger to Watson and Crick to recombinant DNA technology, scientific rationality within molecular biology has primarily been grounded in the entailments and extensions of conceptual metaphors.