ATLAS OF LANGUAGE

AT-134-027 · ATLAS 251

Modus tollens

Valid form of inference: If P, then Q; not Q; therefore, not P.

Explanation

Valid form of inference: If P, then Q; not Q; therefore, not P. An expected consequence can lead backward to the refutation of its premise.

Example

If it rains, the street is wet; it is not wet; therefore, it is not raining.

Counterexample

From “If P, then Q” and “Q,” it does not validly follow that “P.”

Distinction

Distinction from implication: From “If P, then Q” and “Q,” it does not validly follow that “P.”

Effect on thought and perception

An expected consequence can lead backward to the rejection of its premise.

Resonance

Modus tollens makes a directed relationship perceptible: An expected consequence can lead backward to the rejection of its premise.

Cite this entry

Reich, Michael (Hrsg./ed.): „Modus tollens“. Atlas der Sprache, AT-134-027. ATLAS 251, data model 1.6.0. https://atlasoflanguage.com/concept/AT-134-027

https://atlasoflanguage.com/concept/AT-134-027

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