A Grumpy Computer Scientist
3 min readDec 20, 2021



I will leave you with something that you may like to know though. As it appears that you do have an interest in rational thinking, and I can't pass an opportunity to make sure people understand these things correctly.

That Appeal to Authority (AtA) is a fallacy is a common misconception, and far too common among keyboard debaters.

Normal debates, like the one we are having are not based on deductively valid logic (https://en.wikipedia.org/wiki/Deductive_reasoning), or we would not go very far in any conversation.

These arguments are instead characterized by so called Defeasible Reasoning (https://en.wikipedia.org/wiki/Defeasible_reasoning).

In this context, AtA is a fallacy only in case the Authority called in question is inappropriate, or incompetent, or false or unrepresentative, etc...

More specifically, consider how Appeal to Authority can be invoked in two ways, either as proof or as evidence.

If invoked as proof: if the authority in turn provided a proof, you can just appeal to the proof of the authority. It is up to the receiver to look it up.

If invoked as evidence, if the authority is recognised to have a stronger competence than the evidence it is pitted against, the argument is perfectly fine.

I would add that, in both cases, AtA is an essential tool to all scientific debate. Not to logical r mathematical proofs, mind it. To debate.

Without citation, which can be construed as AtA, no other argument would go very far.

In many cases things are so established that you don't even need to cite them (if you use Godel's incompleteness theorem in a paper, you don't necessarily even cite the original work, you kind of assume it the way you'd assume Pythagora's theorem)

Citing a book or a paper by a recognised expert is not, I repeat, it is not, a fallacy.

There is probably a chain of reasoning that you have to follow, if you read that book, and then other books and even more books after those. But the fact that you don't do that doesn't make the argument invalid. It just means that you are lazy, have better things to do, or just have no reason to doubt that the argument works and you move on.

If you want to dispute a claim that appeals to an expert's work, though, it is not sufficient to say you reject it on the basis that it appeals to something else. You have to read that something else, and reject that on substance.

I will add that the vast majority of the knowledge you have, comes from arguments from authority.

If - like me - you have never been to Paraguay, but you do not dispute its existence. How do you know that? Did you tell your teacher in school that they were making an argument from authority? Did you see it in a book? Did you meet someone who claimed to be from Paraguay? :)

[this reminds me of the case of that city in Germany... ]

Of course, in some cases there is a so called Appeal to False Authority or, in experimental science, what I would call Appeal to Madeup Experiments, and Appeal to Incompetent Experiments... but that's a whole other can of worms :)))

And how could I not cite some source that explains this far better than I can do :)





A Grumpy Computer Scientist

UK-based AI professor interested in AI, mind, science, rationality, digital culture and innovation. Hobbies: incessantly fighting nonsense.