Logic / Unit 1 Logic 016 short lesson, about 20 seconds
Soundness
Captions available
The idea
An argument is sound when it is valid AND all its premises are actually true. Sound arguments guarantee true conclusions.
In practice
"All humans are mortal; Socrates is human; so Socrates is mortal." Valid form, true premises: sound.
Where people slip
Sound is the gold standard. Valid is only half the job.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Something wrong in this lesson? Flag it · Sources for Logic