We’ve heard a lot about campus free speech lately, or the lack thereof. From federal judges heckled at Stanford to speakers shut down at Yale, to various other controversies all over America, the dominant trend on campus seems to be to treat any opposing idea or speech as an act of violence. Ideas with which one disagrees are shunned as dangerous, even threatening—though as a friend observes, anyone who thinks words are violence has never been punched in the mouth.

This behavior is wrong, and we are beginning to see some positive responses from administrators at some schools. After the Stanford debacle, Jenny S. Martinez, the dean of the law school, published a strong and lengthy defense of free speech, including the announcement that all students will attend a seminar on free expression. At Cornell, President Martha Pollock and Provost Michael Kotlikoff recently shot down an effort by the student assembly to require “trigger warnings” in all classes. As the pair wrote,

Academic freedom, which is a fundamental principle in higher education, establishes the right of faculty members to determine what they teach in their classrooms and how they teach it, provided that they behave in a manner consistent with professional ethics and competence, and do not introduce controversial matters unrelated to the subject of their course.

But far too often, university administrators adopt a supine posture towards, and are even complicit in, student hostility to disagreeable ideas. The notion that hearing unwelcome ideas is