For a typical example, what is to be done with neo-Nazis who claim that Jews are inferior to Whites and deserve to be enslaved, imprisoned, or murdered? What is to be done with fundamentalist Christians who say that homosexuals are criminals against God and deserve to burn in eternal fire? As a less familiar yet no less significant example, what is to be done with people who profess something called "moral relativism" and claim that all moral claims are meaningless, that the beliefs of Nazis or nihilists are as sound as the beliefs of liberals or utilitarians?

This sort of speech is not the same as direct incitement to violence—"Jews should be killed"/"Homosexuals should burn" is not the same as "Kill that Jew"/"Burn that homosexual"—nor is it the same as any of the other sorts of speech liberals would ordinarily restrict, such as irresponsible lies that directly endanger people (e.g. yelling "Fire!" in a crowded theater when there is no fire) or perjury in a court of law that would hinder the process of justice. Yet clearly this sort of speech is wrong, not just in a factual sense, but in a moral sense as well; hate speech constitutes a declaration of moral beliefs which are not only false, but harmful, immoral and dangerous.

As such, it seems (at first glance) that we ought to restrict hate speech, make it illegal and punishable in the same way that we make murder or theft (or, more analogously, perjury) illegal and punishable. But then we have a system in which the government has a right to legislate moral statements—and it seems a slippery slope to exactly the sort of "thought police" that liberals most fear. If hate speech is permissible, it is not immoral; but if it is impermissible, should we not make it illegal?

The answer lies in an important but often-neglected distinction: Between that which is permissible—what it is morally acceptable to do—and that which is allowable—what good people ought not to use violence to prevent. (Attack not my etymology, for these are technical terms; I realize that in common usage "permit" and "allow" are close synonyms.)

Obviously, all that is permissible is allowable—one should never use violence to prevent acts that are not immoral!—but importantly, not all that is allowable is permissible. There are acts which are morally wrong (impermissible), yet which are not so wrong that it is justified to use violence to prevent them.

\[ \forall x \in P: x \in A \]

\[ \exists x \in A: x \notin P \]

\[ P \subset A \]

\[ A \not \subset P \]

Hate speech is precisely the sort of act which is impermissible but allowable. Another such act is cutting in line; another is making rude insults. I'd put public nudity in the same category, and probably software piracy as well. Often, these are simply violations of custom, rather than deep moral rules; they are wrong because in these social circumstances they violate contractual obligations of acceptable behavior, not because they are intrinsically harmful. Hate speech is actually a case where we might say that the act is intrinsically harmful—but in this case, the act is still allowable because the cure would be worse than the disease.

What, then, is the proper response to hate speech? More speech! Answer these hateful and atrocious lies with truths, and sound arguments to defend those truths. Minimize the harm now, and attempt to persuade others not to say these words. But remember always that these words, however wrong, are allowable—you have no right to use violence or legal punishment in order to stop them. You need not hold your tongue—indeed, you ought not hold your tongue—but leave laws and guns out of the matter.

Thus, Richard Dawkins' God Delusion and Lily Allen's Fuck You are precisely the correct action to take, and should be applauded as such. When a science teacher tells his student creationism is false and superstitious nonsense,  he is doing precisely what he ought to do—and it is a travesty of justice that this act was punished, for it is not merely allowable, not merely permissible, but outright good, while the creationism he attacked can only achieve the level of allowable.