Logic / Unit 1 Logic 017 short lesson, about 20 seconds
Valid vs. Sound
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The idea
Every sound argument is valid, but not every valid argument is sound. Soundness = validity + true premises.
In practice
The cube-Mars argument (014) is valid but unsound. The Socrates argument is both.
Where people slip
In everyday speech people say "valid point" to mean "true point." In logic, never.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
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