 Lawrence Summers said at a symposium about "The Social and Political Views of American Professors" that he considers it a problem that some academics express an "extreme hostility" to conservative opinions.He observed that faculty who were invited to give Tanner Lectures on Human Values were almost always liberals, and expressed concern that an imbalance in political representation at universities could impede rigorous examination of issues.He also attributed the small numbers of conservative professors largely to the career choices made by people comparing academic careers with other options.