The courtier's reply is an alleged type of informal fallacy, coined by American biologist PZ Myers, in which a respondent to criticism claims that the critic lacks sufficient knowledge, credentials, or training to pose any sort of criticism whatsoever.[1] It may be considered an inverted form of argument from authority, where a person without authority disagreeing with authority is presumed incorrect prima facie.
A key element of a courtier's reply, which distinguishes it from an otherwise valid response that incidentally points out the critic's lack of established authority on the topic, is that the respondent never shows how the work of these overlooked experts invalidates the arguments that were advanced by the critic.
Critics of the idea that the courtier's reply is a real fallacy have called it the "Myers shuffle", implying calling someone out for an alleged courtier's reply is a kind of rhetorical dodge or trick.