This paper tests cognitive mobilization, structural role, and traditional socialization agent theories of political literacy, conceptualized as the potential for informed political participation. Political literacy cannot be measured directly, but we presume that if people are politically literate, they understand party differences and know basic political concepts and facts. Other names for this concept include political expertise, political awareness, and civic competence. Using Jennings and Niemi's youth-parent panel socialization data, we conclude that cognitive mobilization has the largest effect on political literacy, followed fairly closely by structural roles. Socialization agents have a very minor effect. This conclusion partly supports prevailing cognitive mobilization explanations of this concept. However, self-selection causes much of the relationship between political literacy and education, making education's cognitive mobilization potential far smaller than most political scientists assumed. Political involvement and ability are the main sources of cognitive mobilization instead, and education's spurious cross-sectional effect primarily reflects structural roles.
