One famous proverb says “Early to bed and early to rise; makes a man healthy, wealthy and wise.” This proverb highlights the importance of sleep in the simplest words. It tells us that not sleeping properly may cause us to lose health and wisdom, which will ultimately cause us to lose wealth as well, which is not possible without a healthy body and mind.
We need to sleep daily. If we fail to sleep for a couple of days, we are likely to become neurotic. Randy Gardner holds the world record for surviving without sleep. In 1965 Gardner stayed awake for 264 hours (about 11 days) for a high school science project . Studies have also established that people, who were awake for days, did not experience any serious medical, neurological, physiological or psychiatric problems. However, all of them showed progressive and significant deficits in concentration, motivation, perception and other higher mental processes as the duration of sleep deprivation increased. Nevertheless, all experimental subjects recovered to relative normalcy within one or two nights of getting regular sleep. The researches carried out for studying the effect of prolonged sleep deprivation proved that it induces altered states of consciousness (often described as "micro-sleep"), numerous brief episodes of overwhelming sleep, and loss of cognitive and motor functions .
That lack of sleep may cause death is confirmed by scientists. In the case of rats, it was found that continuous sleep deprivation for about two weeks or more inevitably caused death in experiments conducted in Allan Rechtschaffen sleep laboratory at the University of Chicago . Even though, such experiments have not been conducted on human beings, yet there can be no doubt that no man can survive long without sleep.
Scientific Theories of Sleep
The question of the necessity of sleep has not been completely answered, and differences of opinion continue to persist between the experts. Psychologists believe that sleep serves the restorative function, allowing the brain to rest and recover from the wear and tear of the day’s activity. Deprivation of sleep can have serious effect on the physical and mental health of the human beings. Scientists are, however, confused about the true justification for sleep as it does not appear to be necessarily for any physiological reason. This has lead some scientists to even conclude that sleep has no biological function and is simply a sort of habit.
The predominance of evidence, however, suggests two biological functions for sleep. Sleep probably plays a role in the restoration of the body and brain, perhaps facilitating the synthesis of large molecules such as proteins and ribonucleic acids. Sleep may play a more complex role in providing restoration for brain processes—especially some higher-level brain processes involved in focusing attention, waking ego mechanisms, performing subtle cognitive and social tasks, and so on. .
It is, however, not known how sleep restores the body and the brain. The theory of relaxation does not explain the need of sleep. One can simply take rest and relax at bed even without going to sleep. In the physical sense, lying on bed is as much a relaxation as sleeping. Yet mere resting or relaxing cannot substitute sleep which requires the control of all body functions to shift from the mind to an unknown entity.
During sleep physiological functions of the body do not stop and all processes of the body like breathing, heartbeat, metabolism etc are carried out as usual but at a slower rate. During sleep mental functions stop and the person has no consciousness of the time in which he is asleep. For him that part of time does not exist. It is this deep sleep, which is the absolute necessity of life.
What happens during deep sleep is still a mystery. However, since it is necessity of life, we may compare sleep with other necessary ingredients of life like air, water and food to see if we can get some explanation for sleep? If one does not sleep, he would not die due to failure of the physiological functions directly but only due to malfunctioning of mind as sleep affects the mind. If we compare sleep with other ingredients of life, it seems that sleep may be as important for nourishment and functioning of the mind as air, water or food are important for the nourishment and functioning of the physical body. We feel fresh and energetic in the morning after a good night sleep. In no time of the day we have as vibrant and cheerful mind as in the morning. Our energy levels are at the highest in the morning. The conventional scientific logic cannot explain the flow of energy since in the morning our food is already digested so the energy level should be at the lowest.
Sleep: The Aatmic Science Perspective
One of the most fundamental principles of the Aatmic Science is that the body is the material refection of the soul in the same manner as the Universe is the material reflection of the Universal Soul (Paramatma) i.e. God. The relationship of human beings with God is similar to the relationship of cells of the body with the whole human being.
The relationship between the Soul and the material or perceptible world is best expressed in the Gita (VI-1, 4, 5) where Lord Krishna states:
“Earth, Water, Fire, Air, Sky (Ether), Mind, Reason and Ego- thus eightfold are my Nature. This is My lower aspect; but know thou My other aspect, the higher – which is jiva (Atman or Soul) by which this world is sustained. Know that these two compose the source from which all beings spring; I am the origin and the end of the entire Universe.”
In this couplet, Earth, Water, Air, Fire and Sky represent the five states of matter i.e. solid, liquid, gas, plasma (which is the state of fire) and light (energy or electromagnetic waves which fill the sky), which constitute a material being including the human body. It further consists of three realities viz. mind, reason and ego which are not visible but can be felt and measured. The Gita (III, 27) further states:
“All Action is entirely done by the nature of the soul (of man). Man deluded by his ego thinks, “I am the doer”.
Thus as per the philosophy of Gita, the soul and the body are the mirror image of each other and all the actions (of the body) are done automatically by the nature of the soul.
Soul is, however, not a perceptible reality and hence, its study can be made only by its physical manifestation i.e. body and its functions by the application of intuition of human mind which emanates from the soul. This method of ascertaining the truth is scientific as it is similar to the study of gravitational, electrical or magnetic waves from the effect (force) they exert on a material object.
Prana: Breathing or Soul?
In the Indian philosophy, breathing (of air) is called Prana and the most popular application of prana is pranayam that means control (or discipline) of breathing. In the physical body, breathing of air is considered synonymous with life. Prana is a Sanskrit word meaning `breath` that refers to a vital, life-sustaining force of living beings and vital energy in natural processes of the universe. .
Prana, however, also means life force or jiva, which is again synonymous with Aatman or Soul. Thus the action of breathing is closely related to the Soul. While breathing is a perceptible reality, which can be seen and felt and provides the proof of living, soul is an imperceptible reality which can be understood only through its external manifestations like the actions of the body i.e. breathing. If a man has breath, he is surely having a soul. Thus breathing is a conclusive evidence for the presence of soul in any living entity. Therefore, breathing may provide us a significant clue about the importance of sleep.
It is possible for a person to live for five or six weeks without food. One can also live without water for a few days but one can not live for more than six minutes without air . Average respiratory rate varies with age. The average rates corresponding to the age of the person are as following :
Newborns: Average 44 breaths per minute
Infants: 20-40 breaths per minute
Preschool children: 20-30 breaths per minute
Older children: 16-25 breaths per minute
Adults: 12 to 20 breaths per minute
Similarly, the need of sleep for human beings also changes with the growth of human bodies. As a man grows in life, his total sleep requirement also changes. The average sleep of the human beings of different ages is as following. :
Newborn: 16 to 18 hours of sleep a night,
Infants : 14 to 15 hours by age one,
Preschool children: 10 to 12 hours
Older children: 8 to 10. hours
Adults: 6 to 8 hours
Thus the cycle of sleep and breathing reduces in human beings like all other creatures as one grows in life. Children need to breath more frequently and sleep more frequently as compared to adults.
Breathing in, or inhaling, is usually an active movement, with the contraction of the diaphragm muscles needed. At rest, breathing out, or exhaling, is normally a passive process powered by the elastic recoil of the chest, similar to a deflating balloon .
The three states of human mind can be compared to the three stages of breathing. Waking state can be compared to breathing in (inhaling), dream state can be compared with holding the breath, while breathing out (exhaling) can be compared with sleep. Sleep can, thus, be considered to be a passive process, which automatically sets in as soon as the action of the mind is stopped. If one has undergone a long period of activity, he would automatically fall asleep, as soon as his mental activity is over i.e. his mind gets peace.
The human body cannot remain without action even for a moment. On the physical level, innumerable chemical reactions are taking place inside the body every moment, which are creating unwanted chemicals like carbon-dioxide which needs to be taken out of the body quickly, else it would strangulate the person to death.
The air we inhale is roughly 78% nitrogen, 21% oxygen, 0.96% argon and 0.04% carbon dioxide, helium, water, and other gases. The air we exhale is roughly 78% nitrogen, 18% oxygen, 0.96% argon and 4% carbon dioxide . Thus the proportion of carbon-dioxide increases many-fold within a few seconds during the process of breathing. Thus, if the breathing is stopped even for a few minutes, there would be sufficient amount of carbon-dioxide in the body to cause death of the person. Carbon-dioxide may, therefore, be called toxic for the body since it is poisonous for it.
Spiritual Aspect of Sleeping
When we sleep in the night, the activity of our mind stops and our (individual) soul gets connected to the cosmic intelligence of the universe i.e. the Universal Soul or God. The process can be compared to breathing that connects the world inside (human body) with the world outside (the atmosphere) when the air is exhaled. It is the atmosphere or air that connects all life of this world flowing freely from one life to another. Similarly there is an invisible chord that connects all the individual souls with the Universal Soul or God.
In the normal working hours, our mind is always acting and reacting to the external stimuli. However, in night when the activity of the mind is switched off, the subtle connection, which always existed with the Universal Soul, becomes very active and effective. Thus the communication between the individual soul and the Universal Soul becomes strong. Hence, due to direct communication between the soul and God, answers to the difficulties and problems are obtained. Thus, during sleep, our soul comes in contact with God, thereby neutralizing the charges and toxins accumulated during the interaction with the world. Sleep is, therefore, the time when the individual intelligence of the body (soul) communicates with the intelligence of the cellular level i.e. the soul of every cell, thereby neutralizing and detoxifying the souls of the individual organs.
Thus sleep provides remedies of many physical ailments. For example, if you have headache and you are able to get good sleep, your headache would vanish. Similarly almost all ailments of the mind or body like fever, body pain, tensions, depressions etc. subside or get cured after a good and sound sleep. Since, during the sleep the individual soul is connected with the Divine Soul, it receives intellectual energy from the Divine Soul and discharges the mental toxin.
What are the mental toxins? In the material sense the toxic substances are those matters that are injurious to the body and need to be taken out. In the physical sense it is like carbon dioxide which is created due to chemical reactions inside the body. Similarly, there are many mental processes that are toxic to the life of human beings. These processes are created in the mind of every person due to the day- to-day interaction with the external world.
Any unresolved problem is toxic to the mind just like any undigested food is a toxin to the body. These toxins may cause depressions, tensions, stress, guilt, and unpleasant memories. Sleep is known to extricate all these mental toxins from the mind due to the connection of the soul with the Universal Soul.
Where do these mental toxins go? They appear to go back to the universal Soul just like the rivers with all its impurities go to the sea or the carbon-dioxide produced by the metabolic reactions go to the atmosphere. Whether such toxins make the Universal Soul toxic? Perhaps not, since the nature has devised a mechanism for its purification. Different entities of the world have been created to complement each other. Plants absorb the carbon dioxide and by, a photosynthesis process, converts the carbon dioxide to oxygen and makes it useful for the human being. The sea absorbs the toxins from the rivers and provides pure water to the rivers by evaporation caused by the Sun and rains caused by condensation. If there were no flow of water to the sea, it would have dried up due to repeated evaporation every year. If there had been no evaporation and condensation and, consequently, rains, the human, animal and plant lives would not have been sustained. All are thus connected to each other in the most complementary way. The Divine Soul removes the harmful mental toxins from the soul and replaces it with positive thoughts.
Further, by virtue of being connected to the Universal Soul or Intelligence, the individual soul gets fresh knowledge from the Universal Soul (just like the body gets fresh air by breathing in), which gets assimilated in intellectual reactions (like chemical reactions of matter) of the mind. In the waking hours, the active mind, like an active body, absorbs the intellectual reactions of new knowledge with the existing knowledge, thereby creating much useful knowledge and also some toxic knowledge. This toxic knowledge or thoughts have to be removed from the soul during sleep like the toxins and waste of the body are removed by its discharging organs.
Sleep is thus one of the most important activities of all living beings. No living being is known to survive beyond a few minutes, without breathing. However, scientists have not been able to know the purpose of sleep, as they have considered only the physical aspect of the body ignoring the spiritual aspect of it. Sleep is perhaps the deepest form of meditation, which removes our mind from the outside world and connects us to the Universal Soul or God. If the soul of man goes to God after death, it can be assumed that sleep is the next closest encounter of the human soul with God.
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