The prime characteristic of the mind is externalization. The sages found that the flow of the mind was outward and not centred inward. That is the law of life: everything spreads outward from its centre. But there is a force which is trying to draw everything back towards their source and centre. When the externalizing force is overcome, man is able to release that re-integrating force, and in this way finds his Centre. When this is done, his search is over. Life is mastered.

The second characteristic of the mind is constancy of activity. Never for a single moment is the mind still.

The third characteristic is wideness in the range of its activity. Not only in one direction is it active, but in many directions. Now it is here, now it is there and now it is everywhere.

Thus, externalized, constantly active, and flitting from one thing to another, the mind is very difficult to control. To understand it requires much subtlety. It cannot be seen; it cannot be put into a test tube and analysed; it cannot be looked at under a microscope. Although man can do scarcely anything about the mind, the mind can do practically everything about the man! It is so subtle, so abstract, and so totally internal that man finds it very difficult to grasp it. One moment it can expand into the thought of the Pacific Ocean or outer space, and then it can diminish to the thought of a mustard seed or a pinpoint or an atom, and the next, with its centre seemingly within the confines of the human brain, as it were, the mind can think about everything up to infinity. With one leap, it can encompass the whole stellar, lunar and solar systems, and with the same capacity, it can think about something as small as a grain of sand. What a mysterious mind!

The mind assumes three recurring states or conditions in every human being. Your consciousness functions through one or the other of these states (referred to as ‘Avastha’ in Vedantic philosophy). It may be external or it may be internal and, if it is internal, it may be either partially withdrawn or totally withdrawn. The greater part of the time the mind is external and you call this state the “waking state”. When you retire to sleep at night, the mind is partially withdrawn in relation to the external universe, but is still vigorously active within. This you vaguely know as the “dream state”. Here the mind creates a world similar to what you perceive and experience during the first-mentioned state, viz., your waking consciousness.

When the mind goes beyond this dream consciousness, it sinks still deeper, and becomes totally withdrawn and absorbed. This third state that you experience daily is “sound sleep”. Little is known about this state and you hardly even think about it, but actually it is the most significant and vitally important state, for it holds the real clue to your innermost true “Self” right at the very core of your being. In this state of total withdrawal of the mind—a state of sound, dreamless, deep sleep—you come closest to your true, essential inner nature. In this state, the mind is closest to its source and centre, but at the same time it is so totally obliterated that even its innermost and primal “I” thought stands suspended in its function. The barest indication of its latent presence is the unmistakable feeling of “I rested well” or “I slept soundly” of the individual upon emerging into waking consciousness.