Sweet Mother,
How can one distinguish between good and evil in a dream?
In principle, to judge the activities of sleep one needs the same capacity of discrimination as to judge the waking activities.
But since we usually give the name “dream” to a considerable number of activities that differ completely from one another, the first point is to learn to distinguish between these various activities—that is, to recognise what part of the being it is that “dreams”, what domain it is that one “dreams” in, and what the nature of that activity is. In his letters, Sri Aurobindo has given very complete and detailed descriptions and explanations of all the activities of sleep. Reading these letters is a good introduction to the study of this subject and to its practical application .
Ref : Some Answers from The Mother