The biostatistical theory versus the harmful dysfunction analysis, part 1: Is part-dysfunction a sufficient condition for medical disorder?

Christopher Boorse's biostatistical theory of medical disorder claims that biological part-dysfunction (i.e., failure of an internal mechanism to perform its biological function), a factual criterion, is both necessary and sufficient for disorder. Jerome Wakefield's harmful dysfunction analysis of medical disorder agrees that part-dysfunction is necessary but rejects the sufficiency claim, maintaining that disorder also requires that the part-dysfunction causes harm to the individual, a value criterion. In this paper, I present two considerations against the sufficiency claim. First, I analyze Boorse's central argument for the sufficiency claim, the "pathologist argument," which takes pathologists' intuitions about pathology as determinative of medical disorder and conclude that it begs the question and fails to support the sufficiency claim. Second, I present four counterexamples from the medical literature in which salient part-dysfunctions are considered nondisorders, including healthy disease carriers, HIV-positive status, benign mutations, and situs inversus totalis, thus falsifying the sufficiency claim and supporting the harm criterion.