This essay examines how in Reflections on the Revolution in France (1790), Edmund Burke formulates a physiological model based on both ocular and immunological reflex in order to articulate the most “natural” means by which Britons could protect themselves against the dangers of the French uprising. On the one hand, Burke draws from his account of visual trauma first developed in his theory of the sublime in the Philosophical Enquiry (1757; 2nd ed. 1759), whose description of the eye’s function stressed the body’s therapeutic recovery, along with tangible social and political benefits. On the other, he deploys an extensive vocabulary of contagion and vulnerable self-immunization, whose precarious logic often undermines the prospect of securing Britain’s safety. In the historical context of Britain’s emerging endorsement of inoculation’s medical utility, the result is an intricate, often volatile physio-politics that, in Burke’s subsequent arguments in Letters on a Regicide Peace (1795–97), produces an ever more urgent political aggression, including his repeated calls for “a long war” on France.