Really bad nightmare kinds of dreams

Really bad nightmare kinds of dreams are not natural to the sleeper's mind. Therefore, we must assume that they are produced by outside influences, such as what the neighbors are going through in the next apartment, the apartment above or the apartment below, or what a dear friend or relative may be experiencing in daily life. Subjective as they are, the frustrated, confused, even threatening, dreams of this nature are taken to be one's creation or one's own problem. However, this is more than often not true. A child may be tormented by nightmares and wake up screaming, and the solution would be to have it sleep in another room, away from the next-door apartment where the husband and wife are battling, entertaining hateful thoughts. These kinds of quarrels permeate the inner atmosphere one hundred yards around, as far as the loudest voice could be heard if there were no walls. This is why those on the path seek the quiet of a forest, a life away from the city, in order to perform sadhana in their spiritual pursuit. Dreams of capture and chase are not products of one's own mind. They are definitely outside influences. - from Satguru Sivaya Subramuniyaswami'

Lucid dreaming

Lucid dreaming is a state in which the sleeper becomes alert and conscious that he or she is dreaming. The imagery in this state is reported to be more vivid than in non-lucid states, and it is difficult to distinguish between the dream and reality. The dreamer is able to control what is dreamed.
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