Proof by assertion

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Proof by assertion, sometimes informally referred to as proof by repeated assertion, is an informal fallacy in which a proposition is repeatedly restated regardless of contradiction and refutation. [1] The proposition can sometimes be repeated until any challenges or opposition cease, letting the proponent assert it as fact, and solely due to a lack of challengers ( argumentum ad nauseam ). [2] 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. [3]

Proof by assertion can also occur when the evidence cited is actually no different than the assertion itself. An argument that actually contains premises that are all the same as the assertion is thus proof by assertion.

This fallacy is sometimes used as a form of rhetoric by politicians, or during a debate as a filibuster. In its extreme form, it can also be a form of brainwashing. [1] Modern politics contains many examples of proofs by assertion. This practice can be observed in the use of political slogans, and the distribution of "talking points", which are collections of short phrases that are issued to members of modern political parties for recitation, and in order to achieve maximum message repetition. The technique is also sometimes used in advertising. [4]

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In classical rhetoric and logic, begging the question or assuming the conclusion is an informal fallacy that occurs when an argument's premises assume the truth of the conclusion. Historically, begging the question refers to a fault in a dialectical argument in which the speaker assumes some premise that has not been demonstrated to be true. In modern usage, it has come to refer to an argument in which the premises assume the conclusion without supporting it. This makes it an example of circular reasoning.

<span class="mw-page-title-main">Fallacy</span> Argument that uses faulty reasoning

A fallacy is the use of invalid or otherwise faulty reasoning in the construction of an argument that may appear to be well-reasoned if unnoticed. The term was introduced in the Western intellectual tradition by the Aristotelian De Sophisticis Elenchis.

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An appeal to nature is a rhetorical technique for presenting and proposing the argument that "a thing is good because it is 'natural', or bad because it is 'unnatural'." In debate and discussion, an appeal-to-nature argument can considered to be a bad argument, because the implicit primary premise "What is natural is good" has no factual meaning beyond rhetoric in some or most contexts.

Douglas Neil Walton was a Canadian academic and author, known for his books and papers on argumentation, logical fallacies and informal logic. He was a Distinguished Research Fellow of the Centre for Research in Reasoning, Argumentation, and Rhetoric (CRRAR) at the University of Windsor, Ontario, Canada, and before that (2008–2014), he held the Assumption Chair of Argumentation Studies at the University of Windsor. Walton's work has been used to better prepare legal arguments and to help develop artificial intelligence.

Appeal to the stone, also known as argumentum ad lapidem, is a logical fallacy that dismisses an argument as untrue or absurd. The dismissal is made by stating or reiterating that the argument is absurd, without providing further argumentation. This theory is closely tied to proof by assertion due to the lack of evidence behind the statement and its attempt to persuade without providing any evidence.

<i>Reductio ad absurdum</i> Argument that leads to a logical absurdity

In logic, reductio ad absurdum, also known as argumentum ad absurdum or apagogical arguments, is the form of argument that attempts to establish a claim by showing that the opposite scenario would lead to absurdity or contradiction.

The burden of proof is the obligation on a party in a dispute to provide sufficient warrant for its position.

In argumentation theory, an argumentum ad populum is a fallacious argument which is based on claiming a truth or affirming something is good because many people think so.

An argument from authority, also called an appeal to authority, or argumentum ad verecundiam, is a form of argument in which the opinion of an influential figure is used as evidence to support an argument.

References

  1. 1 2 Austin J. Freeley, David L. Steinberg, Argumentation and Debate; Critical Thinking for Reasoned Decision Making (Wadsworth Cengage Learning, Boston, 2009), p. 196
  2. Forensic Science and Law, ed. Cyril H. Wecht, John T. Rago (CRC Press, Boca Raton, 2006), p. 32
  3. "Philosophy in Action: Logical Fallacies on Philosophy in Action". Philosophy in Action. Retrieved 2017-02-17.
  4. Robert Ruxton, 'Selling by the Printed Word', The Printing Art, Vol. xxxix (Cambridge: Cambridge University Press, 1922), p. 60