|Part of the series on|
“”If you need to invoke your academic pedigree or job title for people to believe what you say, then you need a better argument.
|—Neil deGrasse Tyson|
Ipse dixit is a Latin phrase meaning "He himself said it." It refers to what is basically an appeal to authority, with oneself as the authority. In other words, the perpetrator of an ipse-dixitism makes an unfounded assertion and expects his word to be the final say.
For example, Richard Mains asserts a privileged perspective because of his work in space industry without explaining the logic of the relationship between his claims and his claimed experience.
Good old Ayn Rand used her genius to take ipse dixit to a quite superior level by quoting herself as an expert indirectly via some of her own made-up characters in novels. For instance, her "The Virtue of Selfishness" has "Since I am to speak on the Objectivist Ethics, I shall begin by quoting its best representative - John Galt... " John Galt is a fictitious character in Rand's novel Atlas Shrugged.
- P1: A says that X is true
- P2: (implicit) A gets to decide because A is an expert
- C1: X is true