The hypothesis of this episode is that happiness, to a large degree, is dependent upon how we choose to relate to our circumstances. The experiment is to adopt a new perspective in life, which will lead to greater happiness.
Looking at the parable of the Prodigal Son, it is striking that the father of the story (who symbolizes God) goes so far out of his way to make his son happy. We are all God’s children, and God cares about your happiness.
The hypothesis of this episode is that thankfulness is a key component to a happy relationship with God. The experiment is to make a conscious effort to be thankful to God for everything in your life, whether seemingly good or bad.