PrepTest 111, Section 3, Question 11
Teacher to a student: You agree that it(58 more words not shown)
Which one of the following(9 more words not shown)
- AMost people always(3 more words not shown)
- BIt is sometimes(16 more words not shown)
- CBreaking a promise(9 more words not shown)
- DSome implicit promises(8 more words not shown)
- EOne should never(3 more words not shown)
Reading the argument
Which promise takes priority?
The teacher points to an implicit promise to tell the truth whenever we speak to someone. But the student also explicitly promised Jeanne to say she was home sick. If Jeanne is actually well, keeping that explicit promise means lying to the teacher. Telling the truth means breaking the promise to Jeanne.
So 'breaking promises is bad' doesn't yet tell the student what to do. Either choice breaks one of these promises. Why should the promise to the teacher take priority over the promise to a friend? The teacher needs more than the general rule both sides already accept.
What we’re looking for
The necessary assumption should capture that priority. The teacher must think breaking this implicit promise of truthfulness is worse than breaking this explicit promise to Jeanne. Otherwise, the rule against breaking promises hasn't supplied a reason to choose the teacher's preferred action.
Working the answers
- A
Whether most people always tell the truth doesn't settle which promise the student should keep. People could regularly lie, and the teacher could still argue that this student should tell the truth. The argument doesn't need a fact about most people's truth-telling habits.
- B
We don't know that breaking the promise would serve Jeanne's best interests. Perhaps telling the teacher would help her in some way; perhaps it wouldn't. The argument gives no such reason. B might help a different argument about protecting a friend, but here the teacher relies on the obligation to tell the truth.
- C
The teacher doesn't compare the consequences of promise-breaking and lying. More basically, the teacher treats lying as one kind of promise-breaking. The choice is between two promises, not between a lie on one side and the only broken promise on the other. C doesn't identify the priority the teacher needs.
- DCorrect
The implicit promise is the promise to tell the teacher the truth. The explicit one is the promise made to Jeanne. By insisting that the student break the latter rather than the former, the teacher treats at least this implicit promise as worse to break than this explicit one.
That's enough for 'some.' The teacher doesn't have to believe every implicit promise outranks every explicit promise. This particular comparison already commits the argument to the limited claim in D.
- E
The teacher is asking the student to break the promise to Jeanne. So a rule that promises must never be broken wouldn't support the recommended choice; it would forbid it. The argument needs a way to choose between conflicting promises, not an absolute rule that prevents breaking either one.
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