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&lquo;Counsellor Double-Fee” detail from Library of Congress, P&P Online, LC-USZ62-101752Philosophy 103: Introduction to Logic
Argumentum Ad Verecundiam

Abstract: The argument from an irrelevant appeal to authority, the ad verecundiam fallacy, is characterized with examples and shown to be on occasion persuasive but normally fallacious.

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I. Argumentum ad Verecundiam (argument from authority) fallacy: an appeal to the testimony of an authority outside the authority's special field of expertise.

From a logical point of view, anyone is free to express opinions or advice about what is thought true; however, the fallacy occurs when the reason for assenting to a statement is based on following the recommendation or advice of an improper authority. Although many logicians today use the Latin phrase “argumentum ad verecundiam” (or often, more simply, the phrase “ad verecundiam”) as the name of a fallacy, [1] historically those phrases were used for appealing to any authority, relevant or otherwise, as evidence in an argument and were not used specifically to denote the fallacy of appealing to evidence provided by an irrelevant or ill-suited authority.[2]
A. Different kinds of authorities are cited by logicians in different kinds of ad verecundiam fallacies:

(1) experts in a particular field of knowledge (cognitive or epistemic authority);
(2) prestigious or powerful individuals or institutions;
(3) governmental, legal or administrative officials;
(4) social, family, religious, or ancestral heads; and so forth.

In every case, the relevance or appropriateness of the authority's expertise to the question at issue is the essential element under consideration.
B. Occasionally, this argument is called the “argument from prestige” and is based on the belief that respected people are not wrong. In cases where the belief or practices of an elite or privileged group of persons is being cited, the fallacy is often better termed the “snob appeal” variety of the ad populum fallacy.
C. Sometimes it is difficult to distinguish between the ad verecundiam and the ad populum when the authority cited is a group of high-status individuals.
The following example from several logic textbooks is identifiable as either an ad verecundiam or an ad populum fallacy:

“The Inquisition must have been justified and beneficial, if whole peoples invoked and defended it, if men of the loftiest soul founded and created it severally and impartially, and its very adversaries applied it on their own account, pyre answering to pyre.”[3]
D. The informal (or, better, the non-formal) structure of the ad verecundiam fallacy generally has the basic pattern:

Authority on subject x, L says accept statement p.

(p is outside the scope of or not germane to the subject x).

p is true.

E. For example:
Linus Pauling as the only person ever to win two unshared Nobel prizes, one for chemistry, another for peace, stated his daily medication of Vitamin C might have delayed the onset of cancer by twenty years.

(Winning Nobel Prizes in chemistry and for peace does not imply expertise in the medical science of the diagnosis and treatment of malignant neoplasm.)

Therefore, vitamin C is effective in the treatment of cancer.

F. Many advertising campaigns are built on this fallacy. Popular sports figures, musicians, or actors endorse products of which they have no special expertise, and, in this context, this fact is offered as a reason we should use those products.

Even so, occasionally a movie star, for example, might also be an appropriate authority in another field of expertise. For example, former Hollywood actor and union leader Ronald Reagan could have been relevantly quoted as a U.S. political authority at the time of his California governorship or his U.S. presidency. Former Hollywood actor and film director Paul Newman could have been quoted as an authority on professional racing during his motorsports career as team owner and race car driver. The reasoning of these individuals in those respective fields would not ordinarily be open to the charge of an ad verecundiam fallacy.
G. Note also that an ad verecundiam argument cannot be claimed to be a deductive argument since its conclusion does not follow with absolute certainty. Even reliable authorities can be mistaken. Ad verecundiam arguments are always inductive arguments (i.e., arguments whose conclusions are claimed to follow with probability) and are not necessarily fallacious even if the appropriate authorities are found to be mistaken.[4]
For example, in 1948, readers of Science News were invited to buy a fluffy dish towel made from 80 percent cotton and 20 percent asbestos from “Things of Science,” an experiment of the month program provided by Science Service.[5] Concluding that the towel would be safe and useful would not have been an ad verecundiam fallacy even though later the authority in this case, Science Service of the Science News program, was being relied upon. The authority was relevant but simply mistaken. The argument would have been correct at the time even though the conclusion turned out to be false.
II. Examples of the ad verecundiam fallacy:
“I find a second hopeful sign in the fact that many of the finest minds are to-day recoiling from the voice of absolute scepticism. In his book, The Return to Faith, Prof. A. C. Armstrong, Jr., one of the most cautious students of philosophy, has noted with care the indications that ’the day of doubt is drawing to a close.’ … Romanes, the famous biologist, who once professed the most absolute rejection of revealed, and the most unqualified scepticism of natural religion, thinks his way soberly back from the painful void to a position where he confesses that ‘it is reasonable to be a Christian believer,’ and dies in the full communion of the church of Jesus.’”[6]
“The United States policy toward mainland China in the 1980's was surely mistaken because Shirley MacLaine, a well-known actress at the time, emphasized she had grave misgivings about them.”[7]
”Distinguished Scientist Freeman Dyson has called the 1433 decision of the emperor of China to discontinue his country's exploration of the outside world the ‘worst political blunder in the history of civilization.’”[8]
“Advocates for lifting age limits on Plan B [a.k.a., the morning-after pill], including Planned Parenthood president Cecile Richards, insist the pill is universally safe and, therefore, all age barriers should be dropped. From a strictly utilitarian viewpoint, this might be well-advised, but is science the only determining factor when it comes to the well-being of our children? Even President Obama, who once boasted his policies would be based on science and not emotion, has parental qualms about children buying serious drugs to treat a condition that has deeply psychological underpinnings.”[9]

III. Uses of the ad verecundiam.
A. Proper experts and authorities render valuable opinions in their fields, and, ceteris paribus, their testimony should have direct bearing on the argument at hand—especially if we have no better evidence upon which to base a conclusion on securer grounds. For example, Jeremy Bentham describes four important factors determining the cogency of an argument from authority,[10] and Winans and Utterback describe the legitimate use of authority in establishing the truth of the premises of an argument.[11] Even so, the specific relevance of the authority and the truth of the authority's testimony may become further points of contention.
B. To qualify as an authority, the individual must be generally recognized by peers in the same field or, at least, by peers who either hold a similar view or peers who recognize the cogency of the point of view being expressed.
  1. Examine, for yourself, why the condition of citing many authorities in a field would not be an instance of the ad populum fallacy.

  2. The conclusions of relevant authorities are not to be accepted simply on the basis they said so but rather on the basis they conclusions have been reached by reason or experience. Consequently, arguments from authority are most persuasive in the absence of other evidence.

  3. However, in the final analysis, the Royal Society motto should hold sway: Nullius in verba (“take no one's word for it.)”[12]

  4. Issues are not normally decided on the basis of which of various opposing relevant and legitimate authorities are the most illustrious as in the following example:

  5. “… Catulus, moved me as one by someone learned, eloquent, and well prepared … His authority, however, is so great that it clearly would have moved me, if you hadn't apposed it with your own no lesser authority. So I will get to it — though, if I may, I will first say a few words about my own reputation.[13]
IV. Non-fallacious examples of the ad verecundiam:
“Living organisms are the original control systems on this planet. As noted biologist Ernst Mayer puts it, ‘The occurrence of goal-directed [i.e., control] processes is perhaps the most characteristic feature of the world of living organisms.’”[14]

“Former U.S. President George W. Bush said that America would be much stronger if the people would return to traditional American values, and indeed he argues that we should. He says, ‘I am firmly convinced that our greatest problems today — from drugs and welfare dependency to crime and moral breakdown — spring from the deterioration of the American Family. Families must come first in America.’”[15]
“A 1990 survey found 80 percent of economists agreed with the statement increases in the minimum wage cause unemployment among the youth and low-skilled. If you're looking for a consensus in most fields of study, examine the introductory and intermediate college textbooks in the field. Economics textbooks that mention the minimum wage say it increases unemployment for the least skilled worker.”[16]

Although the following passages are considered fallacies by a popular logic textbook, note why they are not fallacious.
“But can you doubt that air has weight when you have the clear testimony of Aristotle affirming that all the elements have weight including air, and excepting only fire?” (Galileo Galilei, Dialogues Concerning Two New Sciences)[17]

“In that melancholy book The Future of an Illusion, Dr. Freud, himself one of the last great theorists of the European capitalist class, has stated with simple clarity the impossibility of religious belief for the educated man of today.” (John Strachey, The Coming Struggle for Power)[18]

“But man, proud man,
Dressed in a little brief authority,
Most ignorant of what he's most assured

Plays such fantastic tricks before high heaven
As make the angels weep”

(William Shakespeare, Measure for Measure Act II, sc. ii, ll 117-121.)


  • 1. See, for example, Douglas Walton, Appeal to Expert Opinion: Arguments from Authority (Philadelphia: Pennsylvania University Press, 2010), 90.

  • 2. In late 17th century, John Locke first used the phrase to describe one of four kinds of commonly used “assent producing devices”: “Whoever backs his tenets with such authorities [‘men, whose parts, learning, eminency, power or some other cause has gained a name’], thinks he ought thereby to carry the cause, and is ready to style it impudence in any one who shall stand out against them. This I think, may be called argumentum ad verecundiam.” John Locke, An Essay Concerning Human Knowledge, (London: Printed for G. and J. Offor et al., 1819), 253. In mid-19th century, Schopenhauer writes, ”Those who are so zealous and eager to settle debated questions by citing authorities, are really glad when they are able to put the understanding and the insight of others into the field in place of their own, which are wanting. … If anyone chances to become involved in such a contest he will do well not to try reason and argument as a mode of defence; for against a weapon of that kind these people … will meet his attack by bringing up their authorities as a way of abashing him—argumentum ad verecundiam, and then cry out that they have won the battle.” Arthur Schopenhauer, The Art of Literature, trans. T. Bailey Saunders (London: Swan Sonnenschien & Company, 1891), 69.

  • 3. Benedetto Croce Philosophy of the Practical: Economic and Ethic 1913 (1913; repr., Biblo & Tannen Publishers, 1969) 69-70.

  • 4. Hamblin prefers to classify arguments from authority as “non-deductive” arguments rather than inductive arguments. He writes, “[T]here are clear cases of arguments that are non-deductive: inductive arguments, statistical or probabilistic arguments, arguments from authority …” C. L. Hamblin Fallacies (London: Methuen & Co. Ltd.: 1970), 249-250.

  • 5. Janet Raloff, "Plumbing the Archives," Science News 181 No.6 (March 24, 2012): 21.)

  • 6. J. T. Plunket, “The Personal Christ, Gospel for Our Time,” in The Presbyterian Quarterly ed. G. B. Strickler, et al.(New York: A. D. F. Randolf Company, 1898), Vol. 12, 549.

  • 7. Described in Charles Stuart Kennedy, Harry E. T. Thayer, Deputy chief of Mission to George Bush, interview The Association for Diplomatic Studies and Training Foreign Affairs Oral History Project Library of Congress (November 19, 1990), 39.

  • 8. Thomas Sowell, “A Historic Catastrophe” Index Journal 97 No. 148 (July 23, 2015), 6A.

  • 9. Kathleen Parker, “Prude or Prudent?” Index-Journal 94 No. 4 (May 5, 2013), 11A.

  • 10. Bentham writes “[T]he weight or influence to be attached to an authority … depends upon: (1) the degree of relative and adequate intelligence of the person in question; (2) the degree of relative probity of the same person; (3) the nearness or remoteness between the subject of his opinion and the question in hand; and (4) the fidelity of the medium through which such supposed opinion has been transmitted, including both correctness and completeness.” Jeremy Bentham, Handbook of Political Fallacies, ed. H. A. Larrabee (New York: Thomas Y. Crowell Company, 1971), 17-18.

  • 11. Winans and Utterback point out that the argument from authority is useful when matters of fact are beyond the knowledge of the disputants and agreement is had as to the relevant authorities. Qualifications of authority obviously depend upon “reputation for intellectual competence” and “reputation for veracity.” James A. Winans and William E. Utterback, Argumentation (New York: The Century Company, 1930), 157-171. In this, these authors follow the more subjective interpretation first presented by the latter 18th century logician Isaac Watts who writes, “When the Argument is fetch'd from the Sentiments of some wise, great, or good Men, whose Authority we reverence, and hardly dare oppose, it is called Argumentum ad Verecundiam as Address to our Modesty.” Isaac Watts, Logick (London: Printed for John Clark et al., 1779), 311. I.e., Watts is suggesting our diffidence to an acknowledged authority.

  • 12. &ldqo;Science progresses by testing a hypothesis against the available evidence obtained through experiment and observation of the natural world. It is not based on the authority or opinion of individuals or institution. In fact the Royal Society motto ‘Nullius in verba’ can be roughly translated as ’take nobody's word for it’. Parliament House of Commons: Science and Technology Committee, 2011 Peer Review in Scientific Publications(Great Britain: Stationery Office, 2011), 103.

  • 13. Cicero, On Academic Scepticism ed. Charles Brittian (Indianapolis, Indiana: Hackett Publishing Company, 2011), 38.

  • 14. Curran F. Douglass, Rationality, Control, and Freedom (London: Rowman & Littlefield, 2015), 97.

  • 15. George Bush, ”Remarks to the National Association of Evangelicals in Chicago Illinois, March 3, 1992,” Public Papers of the Presidents of the United States: George Bush, 1992-3 Book 2 (Washington, DC: US Government Printing Office, 1993), 368.

  • 16. Freeman Dyson is a theoretical physicist. Walter Williams, “Higher Minimum Wages,” Index-Journal 94 No. 301 (February 27, 2013), 7A.

  • 17. I. M. Copi, Introduction to Logic (New York: Macmillan, 1994): 135.

  • 18. I. M. Copi, Introduction to Logic (New York: Macmillan, 1994): 133.

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