Logic / Unit 1 Logic 014 short lesson, about 20 seconds
Valid with False Premises
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The idea
A valid argument can have false premises and a false conclusion — validity only promises: if the premises were true, the conclusion would be too.
In practice
"All planets are cubes; Mars is a planet; so Mars is a cube." Valid. Absurd, but valid.
Where people slip
Calling this "invalid" because it's false is the error video 013 warned about.
Your place on the trail
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