 As bodily tiredness is eased by resting the body, so psychological tiredness is eased by resting the soul. As we have explained in discussing the feelings, pleasure is rest for the soul. And therefore the remedy for weariness of soul lies in slackening the tension of mental study and taking some pleasure… . Those words and deeds in which nothing is sought beyond the soul’s pleasure are called playful or humorous, and it is necessary to make use of them at times for solace of soul (2a2ae, Q. 168, Art. 2).