"Versus: you think I should be forbidden from eating tic-tacs; tic-tacs are nonsentient; therefore you think I should be forbidden from eating nonsentient things"
Isn't that a completely different fallacy?
In the case (C1) "You think it's okay to eat tic-tacs; tic-tacs are sentient; therefore you think it's okay to eat sentient things." You say "You say doing f to A is OK, A is B, therefore, you think it is okay to do f to B". (Because if not, you could not do f to A because A is B)
But in the case (C2) "you think I should be forbidden from eating tic-tacs; tic-tacs are nonsentient; therefore you think I should be forbidden from eating nonsentient things" it is "you think I should not do f to A, A is B, therefore you think I should not do f to B" That is wrong!
If there exist A and C which are all B, then in case C1, we say because f can be done to A, f cannot not be done to B, or else A would not be a member of B (which it is). But in case C2, if f cannot be done to A, then f cannot be done to B reasons the wrong way around: saying something about members of B does not say something about all members of B.
...
Basically, pedantry about the default case of negative statements about groups applying "none of" descriptors and the default case for positive (or atleast non-negative) statements about groups applying "some of" descriptors.
Hiding behind anon account because I didn't want to go through signup hoops before losing my train of thought.
Isn't that a completely different fallacy?
I took the meaning to be "therefore you think there are some nonsentient things I should be forbidden to eat". I agree that as written the other meaning is a more natural interpretation, but in the context of the rest of the article I think my interpretation is more likely (exactly because otherwise it would involve an entirely different logical error). philh, would you like to confirm or refute?
[EDITED to fix an idiotic mistake: for some reason I thought Elo, not philh, was the author. My apologies to both.]
Cross-posted from my blog
I'd like to coin a term. The Sally-Anne fallacy is the mistake of assuming that somone believes something, simply because that thing is true.1
The name comes from the Sally-Anne test, used in developmental psychology to detect theory of mind. Someone who lacks theory of mind will fail the Sally-Anne test, thinking that Sally knows where the marble is. The Sally-Anne fallacy is also a failure of theory of mind.
In internet arguments, this will often come up as part of a chain of reasoning, such as: you think X; X implies Y; therefore you think Y. Or: you support X; X leads to Y; therefore you support Y.2
So for example, we have this complaint about the words "African dialect" used in Age of Ultron. The argument goes: a dialect is a variation on a language, therefore Marvel thinks "African" is a language.
You think "African" has dialects; "has dialects" implies "is a language"; therefore you think "African" is a language.
Or maybe Marvel just doesn't know what a "dialect" is.
This is also a mistake I was pointing at in Fascists and Rakes. You think it's okay to eat tic-tacs; tic-tacs are sentient; therefore you think it's okay to eat sentient things. Versus: you think I should be forbidden from eating tic-tacs; tic-tacs are nonsentient; therefore you think I should be forbidden from eating nonsentient things. No, in both cases the defendant is just wrong about whether tic-tacs are sentient.
Many political conflicts include arguments that look like this. You fight our cause; our cause is the cause of [good thing]; therefore you oppose [good thing]. Sometimes people disagree about what's good, but sometimes they just disagree about how to get there, and think that a cause is harmful to its stated goals. Thus, liberals and libertarians symmetrically accuse each other of not caring about the poor.3
If you want to convince someone to change their mind, it's important to know what they're wrong about. The Sally-Anne fallacy causes us to mistarget our counterarguments, and to mistake potential allies for inevitable enemies.
From the outside, this looks like "simply because you believe that thing".
Another possible misunderstanding here, is if you agree that X leads to Y and Y is bad, but still think X is worth it.
Of course, sometimes people will pretend not to believe the obvious truth so that they can further their dastardly ends. But sometimes they're just wrong. And sometimes they'll be right, and the obvious truth will be untrue.