Sri Aurobindo has described the dream-state of consciousness as the symbolic expression for the inner vital-mental consciousness that functions independently of the physical senses. It is possible to gain possession of the powers of these inner and more subtle levels of awareness, but this requires two distinct steps to be completed. First, we can recognize that as long as we are tied to the physical senses and react to their impulsions, we cannot move the focus inward effectively. The mind continues to follow the sense impressions and gets pulled out to the sights, sounds, smells and sensations delivered by the sense organs. The first requirement therefore is to disassociate the mind from the distracting influence of the sense organs. This does not necessarily means one becomes oblivious to the outer world, however, as the subtle senses that are part of the inner consciousness may still perceive, but in a different form and manner from the physical sensations.
Sri Aurobindo observes: “It is quite possible indeed to be aware in the dream-trance of the outer physical world through the subtle senses which belong to the subtle body; one may be aware of them just so far as one chooses and on a much wider scale than in the waking condition: for the subtle senses have a far more powerful range than the gross physical organs, a range which may be made practically unlimited.”
“In Yoga various devices are used to seal up the doors of the physical sense, some of them physical devices; but the one all-sufficient means is a force of concentration by which the mind is drawn inward to depths where the call of physical things can no longer easily attain to it.”
An example of a physical device is used to achieve this inward state is called tratak. This is a focusing of the gaze intensely on a candle or other illuminated object to such an extent that the viewer becomes one with the candle flame and loses the sense of separateness, and enters into a trance-state as a result.
“A second necessity is to get rid of the intervention of physical sleep. The ordinary habit of the mind when it goes in away from contact with physical things is to fall into the torpor of sleep or its dreams, and therefore when called in for the purposes of Samadhi, it gives or tends to give, at the first chance, by sheer force of habit, not the response demanded, but its usual response of physical slumber. This habit of the mind has to be got rid of; the mind has to learn to be awake in the dream-state, in possession of itself, not with the outgoing, but with an ingathered wakefulness in which, though immersed in itself, it exercises all its powers.”
Sri Aurobindo, The Synthesis of Yoga, Part Two: The Yoga of Integral Knowledge, Chapter 26, Samadhi, pp. 501-502