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For today, let’s understand the Masked-man Fallacy.
What is it?
The masked-man fallacy is a logical fallacy that is committed when someone assumes that if two or more names or descriptions refer to the same thing, then they can be freely substituted with one another, in a situation where that’s not the case. 
The masked-man fallacy could occur if someone claimed that, given that Peter Parker is Spiderman, and given that the citizens of New York know that Spiderman saved their city, then the citizens of New York know that Peter Parker saved their city.
This is because even though Peter Parker and Spiderman are both the same person, what people know about Peter Parker is different from what people know about Spiderman, so it’s wrong to say that just because the citizens of New York know something about Spiderman then they necessarily also know the same thing about Peter Parker. 🤷♂️
Where does it occur?
In debates, counter-arguments between people.
In everyday situations, people often use this fallacy when they assume that if someone supports one aspect of an idea, then it means that they also support other aspects of that idea, that they’re not necessarily aware of.
Why do I need to know?
It is not always proper to replace one term for another even if the two terms designate the same thing, nor can one automatically assume that subjective knowledge of one person (or even of a group) is necessarily enough for making accurate, non-contradictory statements or for teasing out inherently contradictory definitions.
References & Studies: -
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