Proof by assertion, sometimes informally referred to as proof by repeated assertion, is a logical fallacy in which a proposition is repeatedly restated regardless of contradiction. Sometimes this may be repeated until challenges dry up, at which point it is asserted as fact due to its not being contradicted (argumentum ad nauseam). In other cases its repetition may be cited as evidence of its truth, in a variant of the appeal to authority or appeal to belief fallacies.

This logical fallacy is sometimes used as a form of rhetoric

Rhetoric

Rhetoric is the art of discourse, an art that aims to improve the facility of speakers or writers who attempt to inform, persuade, or motivate particular audiences in specific situations. As a subject of formal study and a productive civic practice, rhetoric has played a central role in the Western...

 by politician

Politician

A politician, political leader, or political figure is an individual who is involved in influencing public policy and decision making...

s, or during a debate as a filibuster

Filibuster

A filibuster is a type of parliamentary procedure. Specifically, it is the right of an individual to extend debate, allowing a lone member to delay or entirely prevent a vote on a given proposal...

. In its extreme form, it can also be a form of brainwashing. Modern politics contains many examples of proof by assertions. This practice can be observed in the use of political slogan

Slogan

A slogan is a memorable motto or phrase used in a political, commercial, religious and other context as a repetitive expression of an idea or purpose. The word slogan is derived from slogorn which was an Anglicisation of the Scottish Gaelic sluagh-ghairm . Slogans vary from the written and the...

s, and the distribution of "talking point

Talking point

A talking point in debate or discourse is a succinct statement designed to persuasively support one side taken on an issue. Such statements can either be free standing or created as retorts to the opposition's talking points and are frequently used in public relations, particularly in areas heavy...

s", which are collections of short phrases that are issued to members of modern political parties for recitation to achieve maximum message repetition. The technique is also sometimes used in advertising

Advertising

Advertising is a form of communication used to persuade an audience to take some action with respect to products, ideas, or services. Most commonly, the desired result is to drive consumer behavior with respect to a commercial offering, although political and ideological advertising is also common...

.

The technique is described in a saying, often attributed to Lenin

Vladimir Lenin

Vladimir Ilyich Lenin was a Russian Marxist revolutionary and communist politician who led the October Revolution of 1917. As leader of the Bolsheviks, he headed the Soviet state during its initial years , as it fought to establish control of Russia in the Russian Civil War and worked to create a...

 without citation as "A lie told often enough becomes the truth", although the user may not be intentionally promoting a lie and may just believe an illogical or faulty proposition.

Examples

In his February 2006 talk at the TED conference

TED (conference)

TED is a global set of conferences owned by the private non-profit Sapling Foundation, formed to disseminate "ideas worth spreading"....

, Daniel Dennett

Daniel Dennett

Daniel Clement Dennett is an American philosopher, writer and cognitive scientist whose research centers on the philosophy of mind, philosophy of science and philosophy of biology, particularly as those fields relate to evolutionary biology and cognitive science. He is currently the Co-director of...

 described Rick Warren

Rick Warren

Richard Duane "Rick" Warren is an American evangelical Christian minister and author. He is the founder and senior pastor of Saddleback Church, an evangelical megachurch located in Lake Forest, California, currently the eighth-largest church in the United States...

's book, The Purpose Driven Life

The Purpose Driven Life

The Purpose Driven Life is a devotional book written by Christian author Rick Warren and published by Zondervan. The book has been on the New York Times Best Seller list for advice books for one of the longest periods in history, while also topping the Wall Street Journal best seller charts as...

:

See also

• Argumentum ad lapidem
  Argumentum ad lapidem
  Ad lapidem is a logical fallacy that consists in dismissing a statement as absurd without giving proof of its absurdity. The form of argument employed by such dismissals is the argumentum ad lapidem, or appeal to the stone.Ad lapidem statements are fallacious because they fail to address the...
  
  
• Bare assertion fallacy
• Big Lie
  Big Lie
  The Big Lie is a propaganda technique. The expression was coined by Adolf Hitler, when he dictated his 1925 book Mein Kampf, about the use of a lie so "colossal" that no one would believe that someone "could have the impudence to distort the truth so infamously." Hitler asserted the technique was...
  
  
• Brainwashing
• Denialism
  Denialism
  Denialism is choosing to deny reality as a way to avoid an uncomfortable truth: "[it] is the refusal to accept an empirically verifiable reality...
  
  
• Talking point
  Talking point
  A talking point in debate or discourse is a succinct statement designed to persuasively support one side taken on an issue. Such statements can either be free standing or created as retorts to the opposition's talking points and are frequently used in public relations, particularly in areas heavy...