Argument from authority

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Argument from authority (Argumentum ab auctoritate), also authoritative argument and appeal to authority, is a common form of argument which may give rise to a logical fallacy when misused.[1]

In informal reasoning, the appeal to authority is a form of argument attempting to establish a statistical syllogism.[2] The appeal to authority relies on an argument of the form:

A is an expert on a particular topic
A says says something about that topic
A is probably correct

Fallacious examples of using the appeal include any appeal to authority used in the context of deductive reasoning, and appealing to the position of an authority or authorities to dismiss evidence.[2][3][4][5]


The phrase argumentum ad verecundiam is sometimes used synonymously to mean 'argument from authority'. While it is linked, it does not have the same meaning. The Latin noun verecundia means "modesty" or "shame". Its link to arguments from authority is that they are used to make those who lack authority feel shame about discussing issues they lack credentials of expertise in, and modestly back out of an argument.


The argument from authority can take several forms. As a syllogism, the argument has the following basic structure:[3][4]

A says P about subject matter S.
A should be trusted about subject matter S.
Therefore, P is correct.

The second premise is not accepted as valid, as it amounts to an unfounded assertion that leads to circular reasoning able to define person or group A into inerrancy on any subject matter.[3][4]

The equally fallacious counter-argument from authority takes the form:[6]

B has provided evidence for position T.
A says position T is incorrect.
Therefore, B's evidence is false.

This form is fallacious as it does not actually refute the evidence given by B, merely notes that there is disagreement with it.[6] This form is especially unsound when there is no indication that A is aware of the evidence given by B.[7]

Appeal to non-authorities[edit]

Fallacious arguments from authority often are the result of citing a non-authority as an authority.[3] First, when the inference refers to an inexpert authority, it is an appeal to inappropriate authority, which occurs when an inference relies upon a person or a group without relevant expertise or knowledge of the subject matter under discussion.[4][8]

Also, because the argument from authority is not a logical argument in that it does not argue something's negation or affirmation constitutes a contradiction, it is fallacious to assert that the conclusion must be true.[3] Such a determinative assertion is a logical non sequitur as the conclusion does not follow unconditionally, in the sense of being logically necessary.[9][10]

See also[edit]


  1. ^ "Logical Fallacies". Fall 2008. Retrieved 2014-01-25. 
  2. ^ a b Salmon, M. H. (2006). Introduction to Critical Reasoning. Mason, OH: Thomson Wadsworth. pp. 118–9. 
  3. ^ a b c d e Gensler, Harry J. (2003). Introduction to Logic. New York, NY: Routedge. pp. 333–4. 
  4. ^ a b c d Baronett, Stan (2008). Logic. Upper Saddle River, NJ: Pearson Prentice Hall. p. 304. 
  5. ^ Walton 2008, p. 89.
  6. ^ a b Walton 2008, p. 91.
  7. ^ Walton 2008, p. 92.
  8. ^ See generally Irving M. Copi (1986). Introduction to Logic (7th ed.). Macmillan Publishing Company. pp. 98–99.
  9. ^ Foster, Marguerite H.; Martin, Michael L., eds. (1966). Probability, Confirmation, and Simplicity: Readings in the Philosophy of Inductive Logic. Odyssey Press. [page needed]
  10. ^ Peirce, Charles Sanders et al. (1883) [Digitized Jun 15, 2007]. Studies in logic. By members of the Johns Hopkins university. Little, Brown. ISBN 978-1-236-07583-3. [page needed] (available as a free google eBook)
  • Gensler, Harry J. (2003). Introduction to Logic. New York, NY: Routedge. pp. 333–4. 
  • Baronett, Stan (2008). Logic. Upper Saddle River, NJ: Pearson Prentice Hall. 

Works cited[edit]

  • Walton, Douglas (2008). Informal Logic. London: Cambridge University Press. ISBN 0-521-71380-3.