Latin Name: Argumentum Ad Verecundiam
Also known as the argument from authority or ipse dixit
It’s important to note that this fallacy should not be used to dismiss the claims of experts, or scientific consensus. Appeals to authority are not valid arguments, but nor is it reasonable to disregard the claims of experts who have a demonstrated depth of knowledge unless one has a similar level of understanding and/or access to empirical evidence. However, it is entirely possible that the opinion of a person or institution of authority is wrong; therefore the authority that such a person or institution holds does not have any intrinsic bearing upon whether their claims are true or not.
Logical Form
According to person 1, who is an expert on the issue of Y, Y is true.
Therefore, Y is true.
Example: Not able to defend his position that evolution ‘isn’t true’ Judah says that he knows a scientist who also questions evolution (and presumably isn’t a primate).
Example A
Richard Dawkins, an evolutionary biologist and perhaps the foremost expert in the field, says that evolution is true. Therefore, it’s true.
Explanation: Richard Dawkins certainly knows about evolution, and he can confidently tell us that it is true, but that doesn’t make it true. What makes it true is the preponderance of evidence for the theory.
Example B
Saint Augustine claimed that if you aren’t Catholic, you won’t go to heaven.
Explanation: Some take this statement very seriously and believe it to be true because of Saint Augustine’s status. If you ask some other religious experts, they may not agree with this, especially if they are not of the Catholic faith.
Exception
Be very careful not to confuse “deferring to an authority on the issue” with the appeal to authority fallacy. Remember, a fallacy is an error in reasoning. Dismissing the council of legitimate experts and authorities turns good skepticism into denialism. The appeal to authority is a fallacy in argumentation, but deferring to an authority is a reliable heuristic that we all use virtually every day on issues of relatively little importance. There is always a chance that any authority can be wrong, that’s why the critical thinker accepts facts provisionally. It is not at all unreasonable (or an error in reasoning) to accept information as provisionally true by credible authorities. Of course, the reasonableness is moderated by the claim being made (i.e., how extraordinary, how important) and the authority (how credible, how relevant to the claim).
The appeal to authority is more about claims that require evidence than about facts. For example, if your tour guide told you that Vatican City was founded February 11, 1929, and you accept that information as true, you are not committing a fallacy (because it is not in the context of argumentation) nor are you being unreasonable.
Tip: Question authority — or become the authority that people look to for answers.
References
Hume, D. (2004). An Enquiry Concerning Human Understanding. Courier Corporation.