Can science, which has given us so many blessings, also help us settle disputes about free speech on campus?


Lisa Feldman Barrett, a professor of psychology at Northeastern University, thinks so. She argues in the New York Times that science can “provide empirical guidance for which kinds of controversial speech should and shouldn’t be acceptable on campus and in civil society.” It’s a point that she doesn’t prove, and that poses dangers to which she seems blind.


Barrett writes that science has shown that “abusive” speech damages listeners’ bodies, especially their brains, and should therefore be considered a form of violence. But it has also shown that “merely offensive” speech does not have this effect. So campuses should let Charles Murray speak, since he is offering “a scholarly hypothesis to be debated,” but is not “a provocateur and hatemonger like Milo Yiannopoulos.”


While I am not very familiar with the latter’s work, it certainly seems correct that a speech by Murray (a colleague of mine at the American Enterprise Institute) would be much more likely to generate an intelligent discussion.


Colleges, and collegiate organizations, should take that fact into account when deciding whom to invite. If that’s all that Barrett wants to establish, she does not need to invoke science. Thinking through the mission of a university ought to be enough.


The science she cites does not really help her case. Her judgment about Murray and Yiannopoulos may be correct, but it is not obviously scientific. It’s hard to see how she overcomes this problem.


I suppose colleges could run tests in which random samples of undergraduates were exposed to prospective speakers and before-and-after comparisons of the fine structure of their brains were performed. Even then, though, we might have to take into account that some undergraduate brains are more susceptible to damage than others.


But it’s worse than that. Her factual assertions undermine her conclusion. She emphasizes that it’s “chronic stress” that affects the brain and nervous system: “If you spend a lot of time in a harsh environment worrying about your safety, that’s the kind of stress that brings on illness and remodels your brain.” That seems like an argument for, not against, tolerating a one-off speech by Yiannopoulos.


Nor does Barrett reckon with the fact that her rationale for keeping abusive speech off campus sweeps wider than her objective. If anything that causes “long stretches of simmering stress” is violence, then any professor with a reputation as a tough grader has a lot to answer for. So do traffic engineers, wedding planners and mortgage lenders.


Come to think of it, can an op-ed be sufficiently annoying to rewire a reader’s neurons for the worse? If so, is it too “literally violence”? It might be time for a citizen’s arrest.


Ramesh Ponnuru is a Bloomberg View columnist. For more columns from Bloomberg View, visit http://www.bloomberg.com/view.