Philosophy / Unit 1 Philosophy 0021 short lesson, about 20 seconds
Soundness
Captions available
The idea
A sound argument is a valid argument whose premises are all true. Soundness guarantees a true conclusion.
In practice
"All humans are mortal. Socrates is human. So Socrates is mortal." Valid, with true premises—sound.
Where people slip
Valid but unsound is common. Checking the connection is half the work; checking the premises is the rest.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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