Unit 8 · Detecting Reasoning Errors
Student Attendance Rule — Necessary Condition Error
Lesson 4 of 10
About this lesson
"Only those who attend will be allowed" makes attending NECESSARY, not sufficient. Tyler correctly infers that Noah (who doesn’t attend) won’t be allowed. Mia incorrectly assumes that attending alone GUARANTEES being allowed — the rule doesn’t say that.
Chapters
Question
Rule: Only those students who attend the meeting at lunchtime today will be allowed to go on the excursion to the museum next week.
Mia says: "Jayden is going to the meeting today, so he'll definitely be able to go on the excursion."
Tyler says: "Noah's going to cricket practice at lunchtime today, so he won't be able to go on the excursion."
If the information in the box is true, whose reasoning is correct?
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