…Peterson is arguing for the conclusion that atheists cannot justify their moral beliefs. Petersen’s first argument for this conclusion seems to be an appeal to authority. He cites atheist philosopher Michael Ruse defending the idea that ethical judgments are illusory. Now, if this is indeed an appeal to authority then it is a bad one. The problem is that atheists disagree about whether morality is an illusion (Nietzsche), an expression of human sentiment (Hume) or based on objective facts about the world (Plato, Sidgwick, etc.). And, of course, an appeal to authority is fallacious just in case there is disagreement among the experts on the issue in question. This is one such issue. Also, it is not at all clear that Ruse should count as an expert on the metaethical implications of atheism. Ruse is a philosopher of biology. Instead, Peterson should look at Michael Martin (an atheist philosopher of religion) or (even better) David O. Brink (a metaethicist). But again, even if Peterson had cited an actual expert, the argument would still be fallacious as an appeal to authority on an issue about which the authorities don’t agree.
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