Concept

Counterexample

Overview

A counterexample is a specific example that contradicts a claim, hypothesis, or generalization. In logic a counterexample disproves a universally stated claim, and does so rigorously in the fields of mathematics and philosophy. For example, the statement that "student John Smith is not lazy" is a counterexample to the generalization "students are lazy", and both a counterexample to, and disproof of, the universally quantified "all students are lazy."

Overview adapted from Wikipedia (CC BY-SA 4.0; see the article history for authors).

Philosophers who discussed Counterexample

• Edmund Gettier
• Imre Lakatos
• F. C. S. Schiller

Related ideas

• Gorgias (dialogue)
• Callicles
• Philosophy
• Mathematics
• Geometry
• Hypothesis
• Natural number
• Plato
• Prima facie
• Socrates
• Logic
• Deductive reasoning
• Rigour
• Universal quantification

Place in the tradition

Part of American philosophy.

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