Argument from authority

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An argument from authority, also called an appeal to authority, is a form of logical and persuasive argument using expert opinion to defend the likelihood of the reliability of a claim. More precisely, it is a defeasible argument and a statistical syllogism taking this form:

X is an expert on subject Y,
X claims A. A is within subject Y.
A is probably true as it is in the expert's field.[1]

The argument can lead to an informal fallacy when misused.[2]

  • A valid argument (Latin:argumentum ad auctoritatem)[3] is one in which a recognized authority on the relevant subject is appealed to by citing a statement by that authority. This is a form of inductive reasoning in that the conclusion is not logically certain, but likely.[4]
    • Examples include following the treatments prescribed by a medical doctor, or citing a respected author to establish claims of fact in a written work. [4]
  • An invalid argument (Latinargumentum ad verecundiam)[3][5], translated from Latin as argument to modesty or respect[6][7], by which the authority appealed to is compromised in some way; such as being an expert in the wrong subject; or being unfamiliar with a specialized aspect of the subject; or giving views from one side of a controversy. [4]
    • Examples: citing a popular astrophysicist for claims about molecular biology; an Olympic athlete's endorsement of a product they do not use[5][8]; or a long retired professor's claims about a current debate in their field. This fails in that the first proposition is untrue.[4]


Historically, opinion on the appeal to authority has been divided as it is listed as a valid argument as often as a fallacious argument in various sources.[9]

John Locke, in his 1690 Essay Concerning Human Understanding, was the first recorded to identify argumentum ad verecundiam as a specific category of argument.[10] He noted that it can be misused by taking advantage of the "respect" and "submission" of the reader or listener to persuade them to accept the conclusion.[11] Over time, logic textbooks started to adopt and change from Locke's terminology to refer more specifically to fallacious uses of the argument from authority.[12] By the mid-twentieth century, it was common for logic textbooks to refer to the "Fallacy of appealing to authority," even while noting that "this method of argument is not always strictly fallacious."[13]

In the Western rationalistic tradition and in early modern philosophy, appealing to authority was considered a logical fallacy.[14][15]

More recently, logic textbooks have shifted to a less blanket approach to these arguments, now often referring to the fallacy as the "Argument from Unqualified Authority"[16] or the "Argument from Unreliable Authority".[17]

However, these are still not the only recognized forms of appeal to authority. For example, a 2012 guidebook on philosophical logic describes appeals to authority not merely as arguments from unqualified or unreliable authority, but as arguments from authority in general. In addition to appeals lacking evidence of the authority's reliability, the book states that arguments from authority are fallacious if there is a lack of "good evidence" that the authorities appealed to possess "adequate justification for their views."[18]

And there are other recognized fallacious arguments from authority. Among them, the "Fallacies" entry by Bradley Dowden in The Internet Encyclopedia of Philosophy states that "appealing to authority as a reason to believe something is fallacious ... when authorities disagree on this subject (except for the occasional lone wolf)"[19] The "Fallacies" entry by Hans Hansen in The Stanford Encyclopedia of Philosophy similarly states that "when there is controversy, and authorities are divided, it is an error to base one’s view on the authority of just some of them."[20] However, Hansen's entry in The Stanford Encyclopedia of Philosophy does not appear to share Dowden's exception regarding "lone wolf" dissenting authorities.

Appeal to non-authorities[edit]

Fallacious arguments from authority can also be the result of citing a non-authority as an authority or citing an expert on a conversational subject.[21] A example of the fallacy of appealing to an authority in an unrelated field would be citing Albert Einstein as an authority for a determination on religion when his primary expertise was in physics.[21] The attributed authority might not even welcome their citation, as with the "More Doctors Smoke Camels" ad campaign[22], which illustrates how the fallacy occurs in accepting his an authority's opinion alone without considering the evidence. [23]

It is also a fallacious ad hominem argument to argue that a person presenting statements lacks authority and thus their arguments do not need to be considered.[24] As appeals to a perceived lack of authority, these types of argument are fallacious for much the same reasons as some uses of an appeal to authority.

Other related fallacious arguments assume that a person without status or authority is inherently reliable. For instance, the appeal to poverty is the fallacy of thinking that someone is more likely to be correct because they are poor.[25] When an argument holds that a conclusion is likely to be true precisely because the one who holds or is presenting it lacks authority, it is a fallacious appeal to the common man.[26]

Notable example[edit]

Inaccurate chromosome number[edit]

In 1923, leading American zoologist Theophilus Painter declared, based on poor data and conflicting observations he had made,[27][28] that humans had 24 pairs of chromosomes. From the 1920s to the 1950s, this continued to be held based on Painter's authority,[29][30][31][28] despite subsequent counts totaling the correct number of 23.[27][32] Even textbooks[27] with photos showing 23 pairs incorrectly declared the number to be 24[32] based on the authority of the then-consensus of 24 pairs.[33][29]

This seemingly established number created confirmation bias among researchers, and "most cytologists, expecting to detect Painter's number, virtually always did so".[33] Painter's "influence was so great that many scientists preferred to believe his count over the actual evidence",[32] to the point that "textbooks from the time carried photographs showing twenty-three pairs of chromosomes, and yet the caption would say there were twenty-four".[32] Scientists who obtained the accurate number modified[34] or discarded[35] their data to agree with Painter's count.

Psychological basis[edit]

An integral part of the appeal to authority is the cognitive bias known as the Asch effect.[29] In repeated and modified instances of the Asch conformity experiments, it was found that high-status individuals create a stronger likelihood of a subject agreeing with an obviously false conclusion, despite the subject normally being able to clearly see that the answer was incorrect.[36]

Further, humans have been shown to feel strong emotional pressure to conform to authorities and majority positions. A repeat of the experiments by another group of researchers found that "Participants reported considerable distress under the group pressure", with 59% conforming at least once and agreeing with the clearly incorrect answer, whereas the incorrect answer was much more rarely given when no such pressures were present.[37]

Scholars have noted that the academic environment produces a nearly ideal situation for these processes to take hold, and they can affect entire academic disciplines, giving rise to groupthink. One paper about the philosophy of mathematics for example notes that, within mathematics,

If...a person accepts our discipline, and goes through two or three years of graduate study in mathematics, he absorbs our way of thinking, and is no longer the critical outsider he once was...If the student is unable to absorb our way of thinking, we flunk him out, of course. If he gets through our obstacle course and then decides that our arguments are unclear or incorrect, we dismiss him as a crank, crackpot, or misfit.[38]

See also[edit]


  1. ^ 1942-, Walton, Douglas (Douglas Neil), (2008-01-01). Informal logic : a pragmatic approach. Cambridge University Press. ISBN 9780521713801. OCLC 783439050. 
  2. ^ J., Gensler, Harry (2010-01-01). The A to Z of logic. Scarecrow. ISBN 9780810875968. OCLC 901202870. 
  3. ^ a b Mark, Bedau,; C., Parke, Emily (2009-01-01). The ethics of protocells : moral and social implications of creating life in the laboratory. MIT Press. ISBN 9780262012621. OCLC 897007177. 
  4. ^ a b c d H., Salmon, Merrilee (2013-01-01). Introduction to logic and critical thinking. Wadsworth. ISBN 9781133049753. OCLC 898667923. 
  5. ^ a b Hansen, Hans, "Fallacies", The Stanford Encyclopedia of Philosophy (Summer 2015 Edition), Edward N. Zalta (ed.), URL =
  6. ^ Worcester, Joseph Emerson (1910). Worcester's academic dictionary: a new etymological dictionary of the English language. Lippincott. p. 661. Retrieved 16 April 2017. 
  7. ^ Walton, Douglas (1 November 2010). Appeal to Expert Opinion: Arguments from Authority. Penn State Press. p. 32. ISBN 0-271-04194-3. Retrieved 16 April 2017. 
  8. ^ "Fallacies | Internet Encyclopedia of Philosophy". Archived from the original on 30 Mar 2017. Retrieved 16 Apr 2017. 
  9. ^ Underwood, R.H. (1994). "Logic and the Common law Trial". American Journal of Trial Advocacy: 166. 
  10. ^ Hamblin, C. L. (1970). Fallacies. London: Methuen Publishing. p. 171. ISBN 0416145701. 
  11. ^ Walton, Douglas (1997). Appeal to Expert Opinion. Penn State University Press. p. 53. ISBN 0271016957. 
  12. ^ Walton, Douglas (1997). Appeal to Expert Opinion. Penn State University Press. pp. 54–55. ISBN 0271016957. 
  13. ^ Coleman, Edwin (1995). "There is no Fallacy of Arguing from Authority". Informal Logic. 17 (3): 366–7. Retrieved 12 January 2016. 
  14. ^ Williams, Jeffrey (2013). PC Wars: Politics and Theory in the Academy. Psychology Press. p. 55. 
  15. ^ Habjan, Jernej. "The Bestseller as the Black Box of Distant Reading: The Case of Sherlock Holmes" (PDF). Primerjalna knjizevnost: 103. 
  16. ^ Hurley, Patrick (2012). A Concise Introduction to Logic (12th ed.). Cengage Learning. pp. 138–9. ISBN 1285196546. 
  17. ^ Layman, Charles (1999). The Power of Logic. Mayfield Publishing Company. p. 178. ISBN 0767406397. 
  18. ^ Nolt, John; Rohatyn, Dennis; Varzi, Achille (2012). Schaum's Easy Outline of Logic. The McGraw-Hill Companies. p. 115. ISBN 0071777539.
  19. ^ Dowden, Bradley. "Fallacies". The Internet Encyclopedia of Philosophy. IEP. ISSN 2161-0002. Retrieved 27 August 2016. 
  20. ^ Hansen, Hans. "Fallacies". The Stanford Encyclopedia of Philosophy (Summer 2015 ed.). The Metaphysics Research Lab, Center for the Study of Language and Information, Stanford University. ISSN 1095-5054. Retrieved 3 September 2016. 
  21. ^ a b Carroll, Robert. "Appeal to Authority". The Skeptic's Dictionary. 
  22. ^
  23. ^
  24. ^ Williamson, Owen. "Master List of Logical Fallacies". The University of Texas at El Paso. 
  25. ^ Ruggiero, Tim. "Logical Fallacies". 
  26. ^ Bennett, B. "Appeal to the Common Man". Logically Fallacious. 
  27. ^ a b c Glass, Bentley (1990). Theophilus Shickel Painter (PDF). Washington, DC: National Academy of Sciences. pp. 316–317. 
  28. ^ a b Mertens, Thomas (October 1979). "The Role of Factual Knowledge in Biology Teaching". The American Biology Teacher. 41. doi:10.2307/4446671. 
  29. ^ a b c Sheldon, Brian; Macdonald, Geraldine (2010). A Textbook of Social Work. Routledge. p. 40. 
  30. ^ O'Connor, Clare (2008), Human Chromosome Number, Nature, retrieved April 24, 2014 
  31. ^ Gartler, Stanley (2006). "The Chromosome Number in Humans: A Brief History". Nature Reviews Genetics. 7: 656. 
  32. ^ a b c d Orrell, David PhD. (2008). The Future of Everything: The Science of Prediction. pp. 184–185. 
  33. ^ a b Kevles, Daniel J. (1985). "Human Chromosomes--Down's Disorder and the Binder's Mistakes" (PDF). Engineering and Science: 9. 
  34. ^ T. C., Hsu (1979). "Out of the Dark Ages: Human and Mammalian Cytogenetics: An Historical Perspective" (PDF). Cell. 
  35. ^ Unger, Lawrence; Blystone, Robert (1996). "Paradigm Lost: The Human Chromosome Story" (PDF). Bioscene. 
  36. ^ McLeod, Samuel (2008), Asch Experiment, Simply Psychology 
  37. ^ Webley, Paul, A partial and non-evaluative history of the Asch effect, University of Exeter 
  38. ^ David, Phillip J.; Hersh, Reuben (1998). New Directions in the Philosophy of Mathematics (PDF). Princeton University Press. p. 8. 

External links[edit]