Making the false assumption that when presented with an either/or possibility, that if one of the options is true that the other one must be false. This is when the “or” is not explicitly defined as being exclusive . This fallacy is similar to the unwarranted contrast fallacy.
Examples:
- I can’t stop eating these chocolates. I really love chocolate, or I seriously lack willpower. I know I really love chocolate; therefore, I cannot lack willpower.
Synonyms: the fallacy of the alternative disjunct, false exclusionary disjunct, affirming one disjunct, the fallacy of the alternative syllogism, asserting an alternative, improper disjunctive syllogism, fallacy of the disjunctive syllogism