The Passive Voice and Social Values in Science
http://baywood.metapress.com/link.asp?target=contribution&id=EFMRBJF3CE4184KK
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  peer-reviewed

Ding, Daniel D.
Journal of Technical Writing and Communication
2002

Abstract:

This article claims that two social values in science--falsifiability of science and cooperation among scientists--determine use of passives in scientific communication. Scientists do not always develop valid theories, so scientific experiments must be amenable to being repeated and found invalid. This requires that the experiments must not be discrete events. Science is also a cooperative enterprise. As an integral part of science, scientific writing employs more passives than actives to focus on materials, methods, figures, processes, tables, concepts, etc. Use of passives to focus on the physical world helps de-emphasize discreteness of scientific experiments. Besides, it also helps remove personal qualifications of observing experimental results. Finally, it enhances cooperation among working scientists by providing a common knowledge base of scientific work--things and objects. Looked at in this way, the passive voice in scientific writing represents professional practices of science instead of personal stylistic choices of individual scientists.