Logic / Unit 3 Logic 081 short lesson, about 20 seconds
Subcontraries
Captions available
The idea
I and O are subcontraries: they cannot both be false, but can both be true.
In practice
"Some voters approve" and "some do not" — happily true together.
Where people slip
Same fine print as contraries: traditional interpretation only.
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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