As you probably know, in sleep you constantly move between the phases of dreamless sleep and the dream state. Similarly, in wakefulness most people only shift between ordinary unconsciousness and deep unconsciousness.
What I call ordinary unconsciousness means being identified with your thought processes and emotions, your reactions, desires, and aversions. It is most people’s normal state. In that state, you are run by the egoic mind, and you are unaware of Being. It is a state not of acute pain or unhappiness but of an almost continuous low level of unease, discontent, boredom, or nervousness — a kind of background static. You may not realize this because it is so much a part of “normal” living, just as you are not aware of a continuous low background noise, such as the hum of an air conditioner, until it stops. When it suddenly does stop, there is a sense of relief. Many people use alcohol, drugs, sex, food, work, television, or even shopping as anesthetics in an unconscious attempt to remove the basic unease. When this happens, an activity that might be very enjoyable if used in moderation becomes imbued with a compulsive or addictive quality, and all that is ever achieved through it is extremely short-lived symptom relief.
The unease of ordinary unconsciousness turns into the pain of deep unconsciousness — a state of more acute and more obvious suffering or unhappiness — when things “go wrong,” when the ego is threatened or there is a major challenge, threat, or loss, real or imagined, in your life situation or conflict in a relationship. It is an intensified version of ordinary unconsciousness, different from it not in kind but in degree. In ordinary unconsciousness, habitual resistance to or denial of what is creates the unease and discontent that most people accept as normal living. When this resistance becomes intensified through some challenge or threat to the ego, it brings up intense negativity such as anger, acute fear, aggression, depression, and so on. Deep unconsciousness often means that the pain-body has been triggered and that you have become identified with it. Physical violence would be impossible without deep unconsciousness. It can also occur easily whenever and wherever a crowd of people or even an entire nation generates a negative collective energy field.
The best indicator of your level of consciousness is how you deal with life’s challenges when they come. Through those challenges, an already unconscious person tends to become more deeply unconscious, and a conscious person more intensely conscious. You can use a challenge to awaken you, or you can allow it to pull you into even deeper sleep. The dream of ordinary unconsciousness then turns into a nightmare.
If you cannot be present even in normal circumstances, such as when you are sitting alone in a room, walking in the woods, or listening to someone, then you certainly won’t be able to stay conscious when something “goes wrong” or you are faced with difficult people or situations, with loss or the threat of loss. You will be taken over by a reaction, which ultimately is always some form of fear, and pulled into deep unconsciousness. Those challenges are your tests. Only the way in which you deal with them will show you and others where you are at as far as your state of consciousness is concerned, not how long you can sit with your eyes closed or what visions you see.
So it is essential to bring more consciousness into your life in ordinary situations when everything is going relatively smoothly. In this way, you grow in presence power. It generates an energy field in you and around you of a high vibrational frequency. No unconsciousness, no negativity, no discord or violence can enter that field and survive, just as darkness cannot survive in the presence of light.
from: http://spiritlibrary.com/eckhart-tolle/ordinary-unconsciousness-and-deep-unconsciousness