The truth-seeking function of universities does not work properly without the presence of diverse viewpoints. This is especially true when it comes to contested social and political questions. Taboos, blind spots, groupthink and the politicization of scientific standards haven't just made academic research narrower and worse, these trends have alienated the general public and reduced public confidence in higher education ... across the ideological spectrum. Unsurprisingly, the increasing ideological conformity of the professoriate is reflected in the decreasing range of ideas that students encounter in the classroom. A recent national study shows a narrow range of perspectives included on undergraduate syllabi on such controversial topics as the conflict between Israel and Palestine, racial bias in the criminal justice system, and abortion. Professional training does not make professors immune to ordinary human biases. Today's cohort of scholarly experts remains vulnerable to the same "tyranny of public opinion" and "uncritical and intemperate partisanship" that the founders of the American Association of University Professors in 1915 warned academia to resist. This means that today's arguments about viewpoint diversity must be considered and judged in their historical and political contexts. [Academic disciplines] have lost a healthy amount of internal contestation, or have turned self-selection and self-governance into ideological capture.