last time I mentioned straw man as the first argumentative foul, today I will continue with the emphasis on unknown authority.
I think that this one is very very famous. Just take the following sentence.
American scientists say that apples are poisonous!
You have hears something like this, starting or ending with some authority. The last time I remember hearing it was when me and some people were talking about what is called: consciousness after death. Few were christians and their opinion is that it proves God. To make their argument stronger they said:
Even scientists proved that some people remembered things when their brain did not show any evidence of functioning!
It is kind of hard to say something against it, because scientists are authority, but unknown. The problem is that nobody else then them knew anything about the authority and it could seem kind of reasonable to believe it, because scientists must be right.
Do not get fooled.
What was their source? Did the source said the same thing? What is their definition of scientist? Why could actually such a thing be true when it collides with the rest of science?
Such an authority can be for example government, or doctors, or people who work there a long time and have experience.
Feel free to share you experience with argumentative foul in comments!