The student probably believes that he is very clever.

Only when he seriously considers the possibility that he is a fool, undermining his preconception, will he be able to recognize what he's doing wrong and determine the correct course of action.

The task is to recognize that the correct answer to the question might not be within our preconceived ideas about what the solution will be. If you assume that either yes or no is the answer, you exclude out of hand the possibility that neither might be.

Recognizing that you've excluded potential solutions without cause is the enlightenment.