103: Introduction to Logic
Argumentum Ad Verecundiam
The argument from an irrelevant appeal to authority, the ad verecundiam fallacy,
is characterized and shown to be on occasion persuasive but normally fallacious.
|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
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
||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
“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.”
||D.The informal (or, better, the
nonformal) structure of the ad verecundiam fallacy generally has the
||Authority on subject
says accept statement p.
(p is outside the scope of or not germane to the
p is true.
E. For example:
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
(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
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.
||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.
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
||“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
||”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
||“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
|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, and Winans and
Utterback describe the legitimate use of authority in establishing the truth of the
premises of an argument. 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
- Examine, for yourself, why the condition of citing many authorities in a field
would not be an instance of the ad populum fallacy.
- 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.
- However, in the final analysis, the Royal Society motto should hold
sway: Nullius in verba (“take no one's word for
- Issues are not normally decided on the basis of which of various opposing
relevant and legitimate authorities are the most illustrious as in the
“… Catulus, moved me as one by someone learned, eloguent, 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
|IV. Non-fallacious examples of the ad
||“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
||“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.’”
||“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
||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)
||“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
“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.)