a contrario

argument

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July 22, 2026

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The phrase "a contrario" is Latin for "from the contrary". It is used in logic to mean "assuming the conditions not covered by the law in question". This is related to the concept of "contraries" in traditional logic, which are two universal categorical propositions that cannot both be true but can both be false. For example, "Every S is P" and "No S is P" are contraries. The opposite or different fact, event, or situation is also referred to as "the contrary".1234

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rhetoric
Basis of agreement and types of argumentation
…an even more evident one), a contrario (arguing from an accepted conclusion to the rejection of its contrary), and the argument of authority. The traditional figures of rhetoric are usually only abridged arguments, as, for instance, a metaphor is an abbreviated analogy.
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…an even more evident one), a contrario (arguing from an accepted conclusion to the rejection of its contrary), and the argument of authority. The traditional figures of rhetoric are usually only abridged arguments, as, for instance, a metaphor is an abbreviated analogy.
Read More