Ad hominem arguments in the service of boundary work among climate scientists

Most accounts of an ideal scientific discourse proscribe ad hominem appeals as one way to distinguish it from public discourse. Because of their frequent use of ad hominem attacks, the Climategate email messages provoked strong criticisms of climate scientists and climate science. This study asks whether the distinction between public and scientific discourse holds in this case and thus whether the exclusion of ad hominem arguments from scientific discourse is valid. The method of analysis comes from the field of informal logic in which argument fallacies like the ad hominem are classified and assessed. The approach in this study focuses on a functional analysis of ad hominem—their uses rather than their classification. The analysis suggests three distinct functional uses of ad hominem remarks among the Climategate emails: (1) indirect, (2) tactical, and (3) meta-. Consistent with previous research on ad hominem arguments in both public and scientific discourse, these results reinforce the common opinion of their fallacious character. Only the remarks of the last type, the meta- ad hominem, seemed to be non-fallacious in that they might help to preempt the very use of ad hominem attacks in scientific discourse.