Logic / Unit 4 Logic 125 short lesson, about 20 seconds
Translating "Unless"
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The idea
"p unless q" translates as p ∨ q.
In practice
"I'll walk unless it rains" — W ∨ R. Equivalently: ~R ⊃ W.
Where people slip
Resist the urge to over-read: "unless" ordinarily doesn't promise what happens if it rains. That extra promise is the exclusive reading, and it needs explicit warrant.
Your place on the trail
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Unlocks
- Nothing yet depends on this.
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