Logic / Unit 7 Logic 331 short lesson, about 20 seconds
Strength Revisited
Captions available
The idea
Inductive strength comes in degrees and moves with evidence — new information can strengthen or weaken an argument without touching its form.
In practice
Add one premise ("the sample was all volunteers") and a strong argument sags.
Where people slip
Validity is immune to new premises; strength never is. That's the deepest difference between the two halves of logic.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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