In
logic
Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the science of deductively valid inferences or of logical truths. It is a formal science investigating how conclusions follow from premise ...
, equivocation ("calling two different things by the same name") is an
informal fallacy
Informal fallacies are a type of incorrect argument in natural language. The source of the error is not just due to the ''form'' of the argument, as is the case for formal fallacies, but can also be due to their ''content'' and ''context''. Fall ...
resulting from the use of a particular word/expression in multiple
senses
A sense is a biological system used by an organism for sensation, the process of gathering information about the world through the detection of stimuli. (For example, in the human body, the brain which is part of the central nervous system rec ...
within an argument.
It is a type of
ambiguity that stems from a phrase having two or more distinct
meanings, not from the grammar or structure of the sentence.
Fallacy of four terms
Equivocation in a
syllogism (a chain of reasoning) produces a
fallacy of four terms
The fallacy of four terms ( la, quaternio terminorum) is the formal fallacy that occurs when a syllogism has four (or more) terms rather than the requisite three, rendering it invalid.
Definition
Categorical syllogisms always have three terms: ...
(). Below are some examples:
: Since only man
uman
Uman ( uk, Умань, ; pl, Humań; yi, אומאַן) is a city located in Cherkasy Oblast in central Ukraine, to the east of Vinnytsia. Located in the historical region of the eastern Podolia, the city rests on the banks of the Umanka River ...
is rational.
: And no woman is a man
ale
: Therefore, no woman is rational.
The first instance of "man" implies the entire human species, while the second implies just those who are male.
: A feather is light
ot heavy
: What is light
right
Rights are legal, social, or ethical principles of freedom or entitlement; that is, rights are the fundamental normative rules about what is allowed of people or owed to people according to some legal system, social convention, or ethical ...
cannot be dark.
: Therefore, a feather cannot be dark.
In the above example, distinct meanings of the word "light" are implied in contexts of the first and second statements.
: All jackasses
ale donkeyhave long ears.
: Carl is a jackass
nnoying person
: Therefore, Carl has long ears.
Here, the equivocation is the metaphorical use of "jackass" to imply a simple-minded or obnoxious person instead of a male donkey.
Motte-and-bailey fallacy
Equivocation can also be used to conflate two positions which share similarities, one modest and easy to defend and one much more controversial. The arguer advances the controversial position, but when challenged, they insist that they are only advancing the more modest position.
See also
*
Antanaclasis
In rhetoric, antanaclasis (; from the el, ἀντανάκλασις, ''antanáklasis'', meaning "reflection", from ἀντί ''anti'', "against", ἀνά ''ana'', "up" and κλάσις ''klásis'' "breaking") is the literary trope in which a sin ...
: a related purposeful rhetorical device
*
Circumlocution
Circumlocution (also called circumduction, circumvolution, periphrasis, kenning, or ambage) is the use of an unnecessarily large number of words to express an idea. It is sometimes necessary in communication (for example, to work around lexical ga ...
: phrasing to explain something without saying it
*
Etymological fallacy
An etymological fallacy is committed when an argument makes a claim about the present meaning of a word based exclusively on that word's etymology. It is a genetic fallacy that holds a word's historical meaning to be its sole valid meaning and th ...
: a kind of linguistic misconception
*
Evasion (ethics)
In ethics, evasion is an act that deceives by stating a true statement that is irrelevant or leads to a false conclusion. For instance, a man knows that another man is in a room in the building because he heard him, but in answer to a question, s ...
: tell the truth while deceiving
*
Fallacy of four terms
The fallacy of four terms ( la, quaternio terminorum) is the formal fallacy that occurs when a syllogism has four (or more) terms rather than the requisite three, rendering it invalid.
Definition
Categorical syllogisms always have three terms: ...
: an ill form of syllogism
*
False equivalence
False equivalence is an informal fallacy in which an equivalence is drawn between two subjects based on flawed or false reasoning. This fallacy is categorized as a fallacy of inconsistency. Colloquially, a false equivalence is often called "com ...
: fallacy based on flawed reasoning
*
If-by-whiskey
Noah S. "Soggy" Sweat Jr. (October 2, 1922February 23, 1996) was an American judge, law professor, and state representative in Mississippi, notable for his 1952 speech on the floor of the Mississippi state legislature concerning whiskey. Reporte ...
: an example
*
Mental reservation
Mental reservation (or mental equivocation) is an ethical theory and a doctrine in moral theology that recognizes the "lie of necessity", and holds that when there is a conflict between justice and veracity, it is justice that should prevail. Th ...
: a doctrine in moral theology
*
Persuasive definition
A persuasive definition is a form of stipulative definition which purports to describe the true or commonly accepted meaning of a term, while in reality stipulating an uncommon or altered use, usually to support an argument for some view, or to cr ...
: skewed definition of term
*
Plausible deniability: a blame shifting technique
*
Polysemy: the property of word or phrase having certain type of multiple meanings
*
Principle of explosion
In classical logic, intuitionistic logic and similar logical systems, the principle of explosion (, 'from falsehood, anything ollows; or ), or the principle of Pseudo-Scotus, is the law according to which any statement can be proven from a ...
: one of the fundamental laws in logic
*
Syntactic ambiguity
Syntactic ambiguity, also called structural ambiguity, amphiboly or amphibology, is a situation where a sentence may be interpreted in more than one way due to ambiguous sentence structure.
Syntactic ambiguity arises not from the range of mean ...
, Amphiboly, Amphibology: ambiguity of a sentence by its grammatical structure
*
When a white horse is not a horse
When a white horse is not a horse is a paradox in Chinese philosophy attributed to Gongsun Long, a philosopher of the Warring States period. It appears in the form of a dialogue between two unnamed speakers who debate the proposition "a white hors ...
: an example
References
{{Fallacies
Verbal fallacies
Ambiguity