The fallacy of equivocation refers to the use of an ambiguous word or phrase in more than one sense within the same argument. Because this change in meaning occurs without warning, it renders the argument invalid or even misleading.
Cause
The fallacy of equivocation involves the use of an ambiguous word or phrase whose meaning changes throughout the argument. This may be due to:
The speaker deliberately switches from the literal to the figurative meaning of a word. For example, “shiny” means “light-reflecting,” but also “intelligent.”
A word has several meanings (a phenomenon called polysemy) and the correct interpretation lies in the context. The word "bank", for example, can refer to either a river bank or a financial institution.
A word resembles another word (for example, they are homonyms) because they share the same pronunciation or spelling. For example, the word "lies" sounds similar to the word "lice", but they have very different meanings.
People sometimes make the mistake of equivocation for comic effect (i.e., as a play on words). In other cases, they may attempt to hide the truth or avoid committing to a point of view. Whether or not the speaker is aware of the equivocation, it remains an error.
How to avoid the equivocation error?
Although we often make the fallacy of equivocation without realizing it, these types of arguments are misleading and are best avoided. here are some questions you can ask to identify this error in your own arguments and those of others:
- Are all terms defined clearly and consistently? This is especially important when we use words or phrases that are open to interpretation. For example, abstract or philosophical terms like “capitalism,” “faith,” or “progress” can mean different things to different people.
- Did a change in meaning occur during the discussion ? Point this out to your interlocutor. You can identify the two different meanings by using two different words or phrases.
- Is the equivocation unintentional? Ask the person making the error to clarify the exact meaning of the term to help them identify the problem in their reasoning.
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