The considerable evidence base linking social conditions to population health has spurred many in public health to call for political action. Most of these conditions fall outside the purview of health departments, meaning that advocates are increasingly calling on other government sectors to improve health. Whether levelled at the whole-of-government or individual departments these calls seek a paradigm shift in governmental goals. Paradigmatic political change is an essentially normative process--one based upon ethical, rather than empirical, reasoning. Successfully achieving political change requires that public health advocates improve their normative justification for change and reduce their reliance upon evidence-based arguments.