Sean Carroll in Preposterous Universe:
How can, and should, we talk to each other, especially to people with whom we disagree? “Free speech” is rightfully entrenched as an important value in liberal democratic societies, but implementing it consistently and fairly is a tricky business. Political theorist Teresa Bejan comes to this question from a philosophical and historical perspective, managing to relate broad principles to modern hot-button issues. We talk about the importance of tolerating disreputable beliefs, the senses in which speech acts can be harmful, and how “civility” places demands on listeners as well as speakers.
More here.