One of the latest things in universities, including at University of California (where I teach) is condemning “microaggressions,” supposed “brief, subtle verbal or non-verbal exchanges that send denigrating messages to the recipient because of his or her group membership (such as race, gender, age or socio-economic status).” Such microaggressions, the argument goes, can lead to a “hostile learning environment,” which UC — and the federal government — views as legally actionable. This is stuff you could get disciplined or fired for, especially if you aren’t a tenured faculty member.