Logic / Unit 1 Logic 015 short lesson, about 20 seconds
Invalid with All True Statements
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The idea
An argument can be invalid even when its premises and conclusion are all true — because the truth didn't come from the form.
In practice
"Paris is in France; grass is green; so water is wet." All true. Zero connection. Invalid.
Where people slip
True conclusion ≠ good argument. This is how lucky guesses masquerade as reasoning.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Unlocks
- Nothing yet depends on this.
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