Josef Pieper, the Thomist philospher and professor at the University of Munster, wrote

As we all know, under [the conditions of tyranny] no one dares to trust anyone else. Candid communication dries up; and there arises that special kind of unhealthy wordlessness which is not silence so much as muteness. This is what happens to human intercourse under the peculiar pressures of dictatorship. Under conditions of freedom, however, human beings speak uninhibitedly to one another. How illuminating this contrast is! For in the face of it, we suddenly become aware of the degree of human closeness, mutual affirmation, communion, that resides in the simple fact that people listen to each other.

Every healthy community puts some boundaries on free speech: no incitement to riot or shouting of fire where there is none. Such restrictions are not tyranny, rather they are the protection of liberty against anarchy. Similarly healthy communities have protections against libel, and requirements for truth, such as in court proceedings. Again, these are not hinderances but aids to ordered liberty. Communities may even hold some words and phrases to be slanderous in and of themselves, offensive to human dignity, and not to be used, such as the N word. Again, restrictions such as this are not tyrannical, but safeguards of true liberty, for their use historically has been to restrict the freedom of those so termed.

But, for healthy community to flourish, as Dr. Pieper points out, people must be free to speak and willing to listen. Conversely, an unhealthy muteness replaces genuine community when under tyranny people are afraid to speak. I think he here specifically refers to our own testimony to events, experiences, perceptions, and especially to ideas.

Of the many bad effects the tyranny of "political correctness" brings, I think the worst is the destruction of human community as we lapse into unhealthy wordlessness over certain issues. Farmer recently pointed out the Cost of Free Speech. What he meant, of course, were the consequences of raising forbidden perceptions and ideas: censure, career damage, labelling. Because of these consequences, most simply do not speak about certain things, becoming mute. And certainly those who are "enlightened" will not listen to another human being if forbidden perceptions or ideas are spoken. Human community is destroyed. Trust is lost.