Some people are located, either by intent or by accident, within closed social cells of politically like-minded associates. Others find themselves in politically diverse settings where participants deftly avoid political discussion in an effort at keeping the peace. Still others, in similarly diverse settings, resemble the moth and the flame—incapable of resisting the temptation to address politics, even when political disagreement is the result. We address the factors giving rise to these circumstances based on the 1996 Indianapolis-St. Louis Study. Our central argument is that political discussion stimulates argumentation, while argumentation impedes discussion, and the combined dynamic helps to explain patterns of persistent disagreement in democratic politics.