“People generally come to agree, when they think it through, that when an activity is of itself attractive enough to make one want to do it, it is play. Much that one does to earn a living may be at times attractive enough so that the individual wants it fo its own sake. Effort is exertion performed to get something done. Play, work, and drudgery are all subjective aspects of the same process; they are attitudes of mind toward the effort. The only foundation for the popular idea that play and work cannot overlap is the time-worn misconception that play is useless, and work, is useful activity.”