An amphiboly fallacy is an error in logic or fallacy that arises from ambiguity or misunderstanding due to grammar, usually through poor punctuation or word choice. This can be a fallacy that is utilized on purpose, or it can happen accidentally as a result of language used hastily or without editing. The nature of this type of fallacy is ambiguity, which means that the argument supported by such a fallacy can easily be argued against by addressing the different possible meanings. An amphiboly fallacy can also be used to great comedic effect, as the phrase plays on the ambiguity for comedic purposes.
As a fallacy of ambiguity, an amphiboly fallacy can be quite similar to a fallacy of equivocation, though there are differences between the two. This type of fallacy occurs due to a grammatical problem that creates the ambiguity or possibility of confusion. Equivocation, on the other hand, is ambiguity that occurs due to poor word choice, usually as a result of someone using a word that he or she feels has one particular meaning, which may have numerous meanings that can be used to point out the weakness of a particular argument. Both types of fallacies create ambiguous meaning in a statement, and should be clarified as part of an argument.
Improper use of punctuation or pronouns is often responsible for creating an amphiboly fallacy. For example, if someone said “The doctor wanted to operate on the patient, but he was not ready,” the “he” is ambiguous and could refer to either the doctor or the patient. While this may not have tremendous impact on the meaning of that particular sentence, usage such as “The doctor wanted to operate on the patient, but he died before surgery” could mean two very different things depending on who “he” refers to in the sentence. This type of fallacy can just as easily end up in a debate or other argument, with ambiguous pronouns obscuring the true meaning of a statement.
Comedians often use an amphiboly fallacy to great effect, as ambiguity can create the comedy within a joke. The comedian Groucho Marx famously used amphiboly in the line “One morning I shot an elephant in my pajamas. How he got into my pajamas I’ll never know.” This, of course, uses amphiboly in the second line; the initial set-up makes the listener picture the speaker wearing pajamas while shooting an elephant. The amphiboly fallacy occurs in the mind of the listener and is used to make the punchline of the joke a surprise, as Marx indicates that somehow the elephant was the one wearing the pajamas.