In previous eras of medical history, when major changes were proposed in customary scientific paradigms, the perceived threats to the status quo led to profound intellectual discomforts. Rational discussion of the proposed changes was sometimes replaced by passionate accusations about ethical behavior. A similar situation may arise in epidemiology today, as fundamental problems are noted in paradigmatic scientific methods, and as the available epidemiologic evidence is used not only in public policy controversies, but particularly in adversarial legal conflicts. When the basic scientific quality of epidemiologic evidence and methods is questioned, defenders of the status quo may respond by castigating the dissenters as fools or heretics, or by insinuating that they have been bribed with consultation honoraria. Since progress in any scientific field requires that problems be suitably recognized and solved, the current disputes about epidemiologic methods should be debated as issues in science, not as transgressions in ethics.