The view of "intellectual diversity" that Horowitz promotes should NOT be seen as a goal of education. The kind of research and teaching that goes on in universities should be guided by the pursuit of truth. Intellectual diversity, in the sense of a variety of viewpoints, is INSTRUMENTALLY useful for this goal of increasing knowledge, because more beliefs gives us a greater chance to defend our ideas and view different sides of an issue. But such diversity of beliefs should not be confused with the goal of truth or knowledge. Yet, this is the confusion that Horowitz makes when he promotes "intellectual diversity." People may be tricked into believing this argument because he appropriates the language of "diversity" from liberals' promotion of racial, gender, and ethnic diversity in affirmative action and hate speech codes. Yet, this kind of diversity is a diversity of identities, while the kind of diversity that Horowitz wants to promote in the classroom is a diversity of beliefs. The former is a plausible goal, while the latter is only instrumentally valuable, (because identities cannot be shown to be mistaken, while beliefs can be). Horowitz exploits the ambiguity between these two senses of diversity in order to make his argument. (Note: in this critique, I am drawing on Stanley Fish's critique of Horowitz's "intellectual diversity" arguments in an article in the Chronicle of Higher Education from 2004, and for the distinction of diversity of beliefs vs. diversity of identities, I draw on Walter Benn Michaels' The Trouble with Diversity: How We Learned to Love Identity and Ignore Inequality).