Abstract In this paper I offer an anti-Humean interpretation of the causal interactions in somatic medicine. I focus on life-threatening pathological states and show how Nancy Cartwright’s capacities can offer a plausible epistemology for medical processes and the singular causal claims advanced in medical diagnoses. I argue that the capacities manifested in the emergence of symptoms and signs could be tracked down if healthy organisms are construed as nomological machines and suggest that the causal reasoning from current medical practice bears (...) a tacit adherence to anti-Humean assumptions. Content Type Journal Article Pages 1-28 DOI 10.1007/s12136-011-0141-1 Authors Stefan Dragulinescu, Drumul Taberei 20, Bucharest, Romania Journal Acta Analytica Online ISSN 1874-6349 Print ISSN 0353-5150. (shrink)