- Tu quoque
"Tu quoque" (
IPA: IPA|/tu ˈkwoʊkwɛ/, Latinfor "You, too" or "You, also") is a Latinterm used to mean an accusation of hypocrisy. The argument states that a certain position is false or wrong and/or should be disregarded because its proponent fails to act consistently in accordance with that position; it attempts to show that a criticism or objection applies equally to the person making it. It is considered an ad hominemargument, since it focuses on the party itself, rather than its positions. [ [http://www.fallacyfiles.org/tuquoque.html Logical Fallacy: Tu Quoque ] ]
In many cases tu quoque arguments are used in a logically fallacious way, to draw a conclusion which is not supported by the premises of the argument.
This form of the argument is as follows::"A" makes criticism "P".:"A" is also guilty of "P".:Therefore, "P" is dismissed.
This is an instance of the two wrongs make a right fallacy.
Example::"He cannot accuse me of
libelbecause he was just successfully sued for libel."
This form of the argument is as follows::"A" makes claim "P".:"A" has "also" made claims which are inconsistent with "P".:Therefore, "P" is false.
This is a logical fallacy because the conclusion that P is false does not follow from the premises; even if A has made past claims which are inconsistent with P, it does not necessarily prove that P is either true or false.
Not all uses of "tu quoque" arguments involve logical fallacy. They can be properly used to bring about awareness of inconsistency, to indirectly repeal a criticism by narrowing its scope or challenging its criteria, or to call into question the credibility of a source of knowledge.
A legitimate use of the you-too version might be::"A" makes criticism "P".:"A" is also guilty of "P".:Therefore, the criticism is confusing because it does not reflect "A"'s "actual" values or beliefs.
Another legitimate use of this version asserts::"A" makes criticism of "P" for "Q".:"A" is also guilty of "Q".:Therefore, the criticism is confusing because it does not reflect A's beliefs.
Example::Version 1: "You say that taking a human life is wrong under all circumstances, but support killing in self-defense; you are either being inconsistent, or you believe that under some circumstances taking a human life is justified.":Version 2: "You claim to believe that taking a human life is always wrong, and you criticize John for it. Contradictory to this, you also support killing in self-defense. You are a hypocrite and are inconsistent in your criticisms."
Note the difference between this legitimate usage and the fallacious one: in the latter, we attempt to use "A"'s hypocrisy to "prove" that criticism "P" is false. This is illogical, since the truth value of a claim does not depend on the speaker. In the former, we are showing that "A" does not make a good critic, therefore arguing for greater skepticism toward his/her claims.
A legitimate use of the inconsistency version might be::"A" makes claim "P".:"A" has "also" made claims which are inconsistent with "P".:Therefore, "A" is an inconsistent source of information.:Inconsistent sources of information are untrustworthy.:Therefore, "A" is an untrustworthy source of information.
Example::"John Smith told the police he was at home alone on Friday night, but later said he was with friends at a bar; we can't take what he says about the crime at face value since he lied about his alibi."
Pot calling the kettle black
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