Mind and various mental experiences are not a purely biologic phenomenon originating from the brain. The mind has travelled with you lifetime after lifetime, along with a lot of baggage.
In each life the mind is integrated with a new body. The brain provides a screen, like a movie screen, on which sensory input and stored memories and impressions can project thoughts, emotions, cravings, aversions, pleasure and pain. Many impressions are carried from past lives.
The mind can be quiet and aware, perceiving clearly, or chaotic, distorted and out of control. A mind acquires a personality built from lifetimes of experiences but this is not who you are. Personalities change, habits and behaviors change, opinions, understandings, values and beliefs change. What we truly are is changeless.
Most people have a sense there is something deeper to their existence, something immortal. Whether we call this something a soul or consciousness or another name, there is something to life beyond the mental activity, beyond the life of the current body we inhabit. We don't know it, but many can feel it.
We cannot distinguish clearly between our mind and consciousness when the mind is subject to a lot of impressions, the samskaras. (Samskaras are mental imprints, the "scars" left behind in the mind from repeated experiences of pain and pleasure and any intense or traumatic experiences).
An Acquired Nature
Throughout many lives every person encounters a unique combination of experiences, each leaving an impression in the mind, and from the sum of those experiences develops an acquired nature; a unique personality with set patterns of thinking, habits and recurring reactions. This acquired nature is not who we are, but it dominates the mind so we appear to be that acquired nature and lose awareness of our true nature.
The busy mind overshadows awareness of our inner nature, restricting and weakening our ability to make clear decisions, or follow through on them. Cravings and the ego prevent our intellect and our higher Will from being in control.
Four Faculties of Mind
The mind has four primary faculties: perceptive and thinking abilities leading to speech and action, (Manas); an intellect which interprets, analyzes, judges, discriminates and forms meanings and concepts (Buddhi); a storehouse of impressions and memories, (Chitta); and ego, a mistaken belief in a unique identity separate from everything else, (Ahankara).
1. Manas: Perception & Expression. Manas is the lower mind which records impressions from our experiences and interacts with the external world through speech & action. Ideally we want our speech and action to follow the directions of a clear and unencumbered intellect. Manas easily falls under the influence of impressions and emotions which distort the intellect leaving Manas to follow whatever urge, attraction, habit pattern or craving that comes in the moment, and this creates many problems and regrets in life.
The lower mind can become accustomed to functioning in a distorted, uncontrolled and chaotic manner and this creates an unstable person. When we think of a 'Willful' child demanding to have his own way this is the lower mind asserting itself. Some never grow out of that stage.
2. Buddhi: Intellect. Buddhi is the higher mind and the gateway to inner wisdom. Buddhi is the faculty that can analyze, judge, discriminate, apply logic and make distinctions. When Buddhi is unhampered by dominate emotions we can live intentionally. We can make clear choices and then Manas can carry out the desired speech & action we choose. Mind-Body practices (yoga, pranayama, Sudarshan Kriya and deep meditation) help develop a stronger, more stable intellect by dissolving impressions and weakening the grip emotions can have over the mind.
When the intellect is compromised by many strong impressions, emotions, and the ego, our decision-making is twisted and in denial. Our speech and actions often do not serve our best interest and are not life-supporting to the world.
Where is the clarity of our intellect when we are overcome by anger, jealousy, passion or greed?
We do things we know we shouldn't do or the distorted intellect rationalizes wrong as right. Many are caught-up in unhealthy habits that harm us yet because they think they find pleasure in these habits they rationalize their indulgence and down-play the harm. Smoking, drinking alcohol and recreational drugs for example.
This is also how crimes are committed. Criminals believe they are doing what is right or necessary because their logic is distorted. They rationalize that what they are doing is right or justify it as "fair". Most criminals never think of themselves as criminals when they commit crimes though they may recognize it in hindsight as they experience the consequences.
Often we see highly educated executives or politicians acting and conspiring to increase their wealth without any regard for the suffering they are causing or the pollution they create. Their minds twist logic to convince themselves that what they are doing is justified. It's amazing how they do this even when they already have more money than they can possibly spend.
If they only understood the suffering they are creating for themselves in the form of future karma they would not act with such greed and selfishness.
3. Chitta: Memory. Chitta is the memories and impressions (samskaras) stored in the mind from events that have passed. Pleasant experiences create cravings to have the experience again. There isn't anything wrong with enjoying, but when cravings dominate, joy is reduced. We crave what we don't have right now. Craving is un-fulfillment and a lack of contentment.
Impressions in the chitta lead the mind to chase after attractive and glamorous things like a hungry dog chases a piece of meat. Every time you indulge in something intensely pleasurable you deepen that impression and the craving that follows.
Unpleasant experiences create aversions and negative emotions which cause repression of feelings as we try to avoid feelings we don't like. Unfortunately, the more we cut off unpleasant feelings we reduce our connection to the good feelings too.
4. Ahankara: Ego. The ego is the faculty of identification. The ego-based mind sees oneself as a unique individual made-up of the physical body, mind and personality. Ego creates the false appearance that we are separate from everyone else. Ego strengthens its identity by causing separation from other people primarily through conflict and withdrawal.
Ego expands by identifying objects, people, memories, status and concepts as 'mine'. All that is 'mine' is a part of 'me'. This explains why billionaires are willing to cause suffering and poison the planet to gain more money they don't need and can't spend; gaining more expands ego.
The higher will-power is our spiritual will and intuition, not something we acquire, but an integral part of our nature. Our intuitive voice can't be heard over a noisy mind. Repeated deep meditation creates the space for the spiritual will to assert itself by dissolving impressions that cause the 'noise' in the mind. A quieter mind is automatically more aware, just as we can hear someone speaking more easily in a quiet room. The higher will-power has a broader awareness which allows us to be more of a witness to the activity in the mind.
As awareness expands we notice that many of our habits and tendencies are not serving our best interest and we summon our will-power to change. We start drawing upon discipline to stop giving-in to every urge and craving that pops-up in the mind and start livin intentionally, with purpose toward a higher goal.
As awareness grows we seek out spiritual wisdom and practices to further the development we intuitively know exists. Most important is deep meditation. Not the meditation of thinking, watching or contemplating but the practice of settling the mind to stillness, (temporary samadhi). In those moments of stillness we dissolve the deepest accumulated samskaras and rejuvenate the mind. This is the path to fulfillment, to enlightenment. With the right practices, stillness of mind, comes effortlessly.