Equivocation

For other uses, see Equivocation (disambiguation).

Equivocation is classified as both a formal and informal logical fallacy. It is the misleading use of a term with more than one meaning or sense (by glossing over which meaning is intended at a particular time). It generally occurs with polysemic words.

It is often confused with amphibology (amphiboly); however, equivocation is ambiguity arising from the misleading use of a word and amphiboly is ambiguity arising from the misleading use of punctuation or syntax.

Examples

Puns

This form of word play relies upon two different words that sound alike. However, their different senses become obvious only upon a moment's reflection. One example is the contrast between birth and death, and birth and berth, and told and toll'd in Thomas Hood's account of the death of Ben the sailor (which took place at the age of 40, contrasted with his age of zero at birth) in his humorous poem Faithless Sally Brown:

His death, which happen'd in his berth,

At forty-odd befell:

They went and told the sexton, and

The sexton toll'd the bell.

Fallacious reasoning

Equivocation is the use in a syllogism (a logical chain of reasoning) of a term several times, but giving the term a different meaning each time. For example:

A feather is light.

What is light cannot be dark.

Therefore, a feather cannot be dark.

In this use of equivocation, the word "light" is first used as the opposite of "heavy", but then used as a synonym of "bright" (the fallacy usually becomes obvious as soon as one tries to translate this argument into another language). Because the "middle term" of this syllogism is not one term, but two separate ones masquerading as one (all feathers are indeed "not heavy", but it is not true that all feathers are "bright"), this type of equivocation is actually an example of the fallacy of four terms.

Semantic shift

The fallacy of equivocation is often used with words that have a strong emotional content and many meanings. These meanings often coincide within proper context, but the fallacious arguer does a semantic shift, slowly changing the context by treating, as equivalent, distinct meanings of the term.

In English language, one equivocation is with the word "man", which can mean both "member of the species, Homo sapiens," and "male member of the species, Homo sapiens." The following sentence is a well-known equivocation:

"Do women need to worry about man-eating sharks?", in which "man-eating" is construed to mean a shark that devours only male human beings.

Metaphor

A separate case of equivocation is metaphor:

All jackasses have long ears.

Carl is a jackass.

Therefore, Carl has long ears.

Here the equivocation is the metaphorical use of "jackass" to imply a stupid or obnoxious person instead of a male donkey.

Switch-Referencing

This occurs where the referent of a word or expression in a second sentence is different from that in the immediately preceding sentence, especially where a change in referent has not been clearly identified.

The following fallacy is an example of amphiboly, and its success relies upon syntactical omissions that obscure an unparallel structure and that result in apparent ambiguity:

"Better than nothing"

Margarine is better than nothing.

Nothing is better than butter.

Therefore, margarine is better than butter.

The fallacy is exposed when the omissions are supplied. Note that, in the first part of the second premise, the present-tense verb, "putting," has been changed to the infinitive, "to put."

[Putting] margarine [on bread] is better than [putting] nothing [on bread].

[However, there is] nothing [to put on bread that] is better than [putting] butter [on bread].

Then note how the meaning would change if the second premise were parallel to the rest of the syllogism:

[Putting] margarine [on bread] is better than [putting] nothing [on bread].

[Putting] nothing [on bread] is better than [putting] butter [on bread].

By supplying the parallel structure, the original conclusion becomes logical.

Therefore, [putting] margarine [on bread] is better than [putting] butter [on bread].

However, by exposing the unparallel structure in the original syllogism, the reader is now able to supply the logical conclusion:

Therefore, [putting] butter [on bread] is better than [putting] margarine [on bread].

Politician's syllogism

A similar example is the Politician's syllogism, satirized on the television show Yes Minister:

Something must be done.

This is something.

Therefore, this must be done.

Specific types of equivocation fallacies

See main articles: False attribution, Fallacy of quoting out of context, No true Scotsman, Shifting ground fallacy.

See also

• Evasion (ethics)
• Fallacy of four terms
• If-by-whiskey

• Mental reservation
• Plausible deniability
• When a white horse is not a horse

References

• F.L. Huntley. "Some Notes on Equivocation: Comment", PMLA: Publications of the Modern Language Association of America Vol. 81, No 1, (March 1966), p. 146.
• A.E. Malloch. "Some Notes on Equivocation", PMLA: Publications of the Modern Language Association of America Vol. 81, No 1, (March 1966), pp 145–146.

External links

• Logical Fallacy: Equivocation The Fallacy Files