Logic / Unit 3 Logic 089 short lesson, about 20 seconds
"Only" and "The Only"
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The idea
"Only S are P" reverses: it means All P are S. "The only S are P" doesn't reverse: All S are P.
In practice
"Only members may enter" — all who enter are members. Not: all members enter.
Where people slip
The single most-missed translation in the subject. When in doubt, ask what the sentence rules out.
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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