Logic / Unit 3 Logic 082 short lesson, about 20 seconds
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The idea
On the traditional square, truth flows downward: A true makes I true; E true makes O true.
In practice
If all whales are mammals, then some are.
Where people slip
Truth flows down; falsity flows up. And on the Boolean reading, nothing flows at all.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Unlocks
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