Jesse Singal: “There’s an intriguing area of behavioral science known as mind-set research, and one of its tenets is that the relationship between stress and humans’ response to it is partially mediated by how people expect stress to affect them. … If you tell students over and over and over that certain variants of free speech – variants which are ugly, but which are aired every moment of every day on talk radio – are traumatizing them, it really could do harm. And there’s no reason to go down this road, because there’s no evidence that the mere presence of a conservative speaker on campus is harming students in some deep psychological or physiological way.”