Still, Blake raises a good question when he asks why universities tolerate professors who support morally reprehensible ideas. Blake thinks the answer is “moral relativism,” but that cannot be right, for, as we saw above, universities have no trouble enforcing moral norms against plagiarism, embezzlement, and the rest. So why mention moral relativism? I suspect the answer is that, if the university held that all ideas were equally good and equally bad, then it would make little sense to punish a professor on the basis of his ideas, and so the university would have a strong policy of academic freedom. In other words, moral relativism implies academic freedom. But even conceding this point arguendo, it is just a logical fallacy (the fallacy of affirming the consequent) to infer the converse and conclude that academic freedom implies moral relativism.
The fallacy becomes obvious when we reflect that there are strong arguments for academic freedom based on objective moral theories. For example, although some academic speech is objectively good and other academic speech is objectively bad, nevertheless limiting academic freedom requires empowering university administrators to decide which speech is good and which is bad, which should be allowed and which suppressed. Empowering people in this way is so dangerous that it is objectively wrong, just as giving teenage boys whiskey and automobiles is objectively wrong. Even when university officials act in good faith, there will be many close calls, and history teems with examples of speech once widely considered bad that we now believe is good, and vice versa. Hence, in any system of speech regulation, the decisions of those running the system will involve a very high error rate, and, even worse, the errors will not be randomly distributed but will skew strongly in favor of ideas with which the officials themselves agree and against ideas with which they disagree.
The fact that there are some easy cases (bestiality is wrong) does not change this; once officials are empowered to decide which speech will be allowed and which suppressed, they will decide not only the easy cases but the hard cases as well. Moreover, the people running the system will not always act in good faith but will sometimes abuse their power to punish those with whose speech they disagree. Indeed, the history of censorship strongly suggests that such abuses are common. On this view, although free speech and academic freedom come at a cost (bad speech is permitted and causes real harm), the costs of a system of censorship are much worse.
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