Why it's a bad idea to tell students that words are violence

A piece by Haidt and Lukianoff contesting several points made by Lisa Friedman in a much discussed NYTimes Grey Matter essay is worth a read. After noting that Friedman makes the valid and well known point that chronic stress can cause physical damage to the body, they contest her logic that follows:

Feldman Barrett used these empirical findings to advance a syllogism: “If words can cause stress, and if prolonged stress can cause physical harm, then it seems that speech—at least certain types of speech—can be a form of violence.” It is logically true that if A can cause B and B can cause C, then A can cause C. But following this logic, the resulting inference should be merely that words can cause physical harm, not that words are violence. If you’re not convinced, just re-run the syllogism starting with “gossiping about a rival,” for example, or “giving one’s students a lot of homework.” Both practices can cause prolonged stress to others, but that doesn’t turn them into forms of violence.

Friedman also notes that brief adversity, like being exposed to a distasteful perspective, can be a 'good kind of stress,' not harmful to the body, but rather building more resilience and strength. She notes further that a political or social climate exposing people to hateful words or casual brutality, can be toxic to the body, and then follows with a second invalid point:

That’s why it’s reasonable, scientifically speaking, not to allow a provocateur and hatemonger like Milo Yiannopoulos to speak at your school. He is part of something noxious, a campaign of abuse. There is nothing to be gained from debating him, for debate is not what he is offering.

Haidt and Lukianoff:

But wait, wasn’t Feldman Barrett’s key point the contrast between short- and long-term stressors? What would have happened had Yiannopoulos been allowed to speak at Berkeley? He would have faced a gigantic crowd of peaceful protesters, inside and outside the venue. The event would have been over in two hours. Any students who thought his words would cause them trauma could have avoided the talk and left the protesting to others. Anyone who joined the protests would have left with a strong sense of campus solidarity. And most importantly, all Berkeley students would have learned an essential lesson for life in 2017: How to encounter a troll without losing one’s cool. (The goal of a troll, after all, is to make people lose their cool.)