The professor holds up a glass of water in class and asks students to guess its weight. After various guesses, he asks what would happen if he held it up for longer periods of time - minutes, hours, days. While the weight would not change, his arm would become sore and numb. He asks the students what he should do to relieve the pain, to which they respond that he should put the glass down. Similarly, we should not dwell on life's problems and stresses, but instead put them down at the end of each day so we can wake up fresh and able to handle challenges in a healthy way.