One day a professor entered the classroom and asked his students to prepare for a surprise test. They waited anxiously at their desks for the test to begin. The professor handed out the question paper, with the text facing down as usual. Once he handed them all out, he asked his students to turn the page and begin. To everyone’s surprise, there were no questions….just a black dot in the centre of the page. The professor seeing the expression on everyone’s face, told them the following:
“I want you to write what you see there.”
The students confused, got started on the inexplicable task.
At the end of the class, the professor took all the answer papers and started reading each one of them aloud in front of all the students. All of them with no exceptions, described the black dot, trying to explain its position in the middle of the sheet, etc. etc. etc. After all had been read, the classroom silent, the professor began to explain: