— Appeal to authority —

Fallacy definition (short name: authority)


From the University of North Carolina :

Often we add strength to our arguments by referring to respected sources or authorities and explaining their positions on the issues we’re discussing. If, however, we try to get readers to agree with us simply by impressing them with a famous name or by appealing to a supposed authority who really isn’t much of an expert, we commit the fallacy of appeal to authority.

From the wikipedia notice :

A (fallacious) appeal to authority argument has the basic form:

  • A makes claim B;
  • there is something positive about A that (fallaciously) is used to imply that A has above-average or expert knowledge in the field, or has an above-average authority to determine the truth or rightness of such a matter
  • therefore claim B is true, or has its credibility unduly enhanced as a result of the proximity and association.

The first statement is called a ‘factual claim’ and is the pivot point of much debate. The last statement is referred to as an ‘inferential claim’ and represents the reasoning process. There are two types of inferential claim, explicit and implicit.
The converse, that (fallaciously) relies on something negative about the source and claims that therefore the conclusion is probably false, is called an ad hominem argument.

Canonical example

Aristotle said two bodies of distinct masses would fall with different velocities, therefore it must be true.

(Galileo contradicted this by experimenting.)

How to avoid it

From UNC :

There are two easy ways to avoid committing appeal to authority:

  • First, make sure that the authorities you cite are experts on the subject you’re discussing.
  • Second, rather than just saying “Dr. Authority believes x, so we should believe it, too,” try to explain the reasoning or evidence that the authority used to arrive at his or her opinion. That way, your readers have more to go on than a person’s reputation. It also helps to choose authorities who are perceived as fairly neutral or reasonable, rather than people who will be perceived as biased.