This may seem very improbable and unnatural to the boy whose studies are enforced and, because they are compulsory, appeal to him as tedious duties which he must perform. But nevertheless it was very natural. Human nature is obstinate and contrary. Tom Sawyer's friends derived much pleasure from whitewashing the fence, and even paid for the privilege. Had their parents set them to whitewashing fences they would have found it irksome work, and anything but play.