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unsound

An argument is unsound if it is invalid or has at least one false premise.

A deductive argument is unsound when it is invalid, or when it is valid but at least one premise is false. An unsound argument fails to establish its conclusion, but its conclusion may still happen to be true.

Examples

  • "All birds can fly. Penguins are birds. So penguins can fly." Valid but unsound.

See also

sound valid
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