Little Johnny’s math grade was so bad that his teacher called home. That afternoon, when Johnny got home, his father stood at the door, clearly upset. “Why did you fail your math test?” his father asked sternly. Johnny simply shrugged and said, “My teacher isn’t very good.”

Surprised by this response, his father urged him to explain further. Johnny began, “On Monday, my teacher said 3+5 equals 8.” His father looked confused. “And?” Johnny continued, “Then on Tuesday, she told us 4+4 equals 8. On Wednesday, she said 6+2 equals 8.” Now it was Johnny’s father’s turn to be astonished. “So what does that have to do with you failing?” he asked. Johnny sighed and explained, “If my teacher doesn’t even know what equals eight, how am I supposed to know the right answer?” His father was left speechless.