Ipse dixit

Cogito ergo sum Logic and rhetoric

Key articles

Logical fallacy Syllogism Argument

General logic

Hoyle's fallacy Open mind Substituting explanation for premise Evil is the absence of God Ecological fallacy Preaching to the choir

Bad logic

Continuum fallacy Nutpicking Moving the goalposts Counterfactual fallacy DARVO Appeal to common sense v - t - e

“”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 book The Virtue of Selfishness states at the beginning, "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.

Form

A says that X is true.

P2: (implicit) A gets to decide because A is an expert.

C: X is true.

See also

• Argument by assertion
• Vicarious autotheism

External links

• False Authority

References

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