Logic / Unit 3 Logic 072 short lesson, about 20 seconds
O Statements
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The idea
O statements — Some S are not P — assert that at least one member of S is outside P.
In practice
"Some employees are not managers."
Where people slip
"Some are not" does not imply "some are." "Some unicorns are not blue" carries no unicorn commitment either way.
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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