Gratifying reveries usually of wish fulfillment. They are images permitted to arise and linger in one's mind for the purpose of giving oneself the illusion of living a life different from real life and to experience whatever sensations may be connected with such an illusion. A person looks for in fantasy what he or she desires in reality, or the thing is not yet attainable (as with the young) or no longer attainable (as with the old).
Daydreams are to be judged morally according to their content and the purpose one has in conjuring up these fancies. To take willful pleasure in wrong things created by the imagination is sinful, e.g., acts of revenge. But even if their content is not improper, daydreams represent a waste of time and energy; they tend to weaken one's character, diminish moral strength and will to pursue the real and possible goals of life, and they prevent the individual from becoming a more useful member of society.