Speech codes and changed attitudes about freedom of speech have created all of these negative feedback loops for expression and critical thinking. As you censor unpopular opinions you end up with classroom environments where individuals can’t really speak their minds. You also end up with students mostly talking to people they already agree with. The research on this is very strong-when you talk to people you already agree with, it thwarts development of critical thinking skills, and it makes people much more confident in what they already believe. It tends to make people more adamant, and exacerbates the serious problem of groupthink.
The whole interview can be read here, or in the May/June print edition of The Humanist. Be sure to check it out!