Did you see something somewhere that makes some sort of distinction between the two? As far as I know, they're the same thing. You can use either term. With a false dichotomy, aka false binary, only 2 options are presented and all other possible options are ignored.
I've never seen a question that makes you distinguish them but for what it's worth:
False binary: something is a spectrum, but the argument is acting like it's not (extreme example: Spiderman is not my favorite movie, therefore it is my least favorite movie)
False dichotomy: more than one of two things could be true, but the argument assumes they are mutually exclusive (example: I like vanilla ice cream, therefore I don't like chocolate ice cream)
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Did you see something somewhere that makes some sort of distinction between the two? As far as I know, they're the same thing. You can use either term. With a false dichotomy, aka false binary, only 2 options are presented and all other possible options are ignored.
I've never seen a question that makes you distinguish them but for what it's worth:
False binary: something is a spectrum, but the argument is acting like it's not (extreme example: Spiderman is not my favorite movie, therefore it is my least favorite movie)
False dichotomy: more than one of two things could be true, but the argument assumes they are mutually exclusive (example: I like vanilla ice cream, therefore I don't like chocolate ice cream)