We are all aware of tile modern concept of the mind as far as modern science and psychology have understood it. However, the yogic concept of the, mind differs from the present day concept.
It is said in the Upanishads that when God had the inherent desire to become many from one, he first created two forces. The first force was known as aditya (prana) and the second force was known as rayi (matter). Sometimes rayi is translated as the total field of consciousness which interacts with the manifest and un-manifest dimension of name, form and idea.
This total field of consciousness goes through a progression which gradually becomes more refined, more subtle and freer from the influences of Nature or the three gunas. This progression of rayi is known in yogic terminology as the states of jagriti, swapna, nidra and turiya, which have been grossly translated as the conscious, subconscious and unconscious mind. It is from this concept that the theory of the mind begins in the present age. What are the experiences of the subconscious, unconscious and superconscious? It is this aspect of mind which modern science is trying to define.
Yoga looks at the mind in a different way. Although for the sake of understanding we often use the word 'mind' in our day-to-day lingo, the total concept has to be understood in a different light: that there is one broad field of consciousness. The word chetana means one who is aware, one who knows that it exists, one who is conscious of itself. This chetana is defined as consciousness in English.
The chetana or rayi of the Upanishads is the self-luminosity of the so-called purusha tattwa of Samkhya philosophy, Shiva of Tantric philosophy or Brahman of Vedantic philosophy. This self-luminous nature Which is both visible and invisible is again classified according to the experiences which it gains in the course of evolution.
The first aspect, and the first manifestation, is known as jagriti, awareness of the interaction which is happening between the self and the world of name, form and idea. I know that I am thinking, and that I am thinking this particular subject. I know that I am feeling and that I am aware of the feeling. I know I am acting and that I am aware of the action. This is the state of jagriti which has been translated as 'wakefulness'. It is being aware of one's actions and interactions, thoughts and behaviour with the individual self and also with the cosmic self.
The next stage is known as swapna. In the state of swapna there is awareness of two different dimensions, although swapna is translated as dream, the dream world or fantasy. According to yogic philosophy, the state of swapna or the state of the subconscious, is the experience of two dimensions happening at one time. The experience which we gained in the waking state is seen in the un-manifest dimension in the inner screen. So, in the swapna state, there is awareness of the visible and also the invisible, the manifest and the un-manifest, the gross world and the subtle world, in harmony with each other. This state is a meditative state. We do not experience the state of swapna at the time of sleep. From distraction of consciousness in the world of name, form and idea, there is concentration of the mental faculties in the swapna state.
The next stage is nidra, absence of awareness of the manifest world, where the attention is not being projected outwards, but is withdrawn in order to see the invisible within. When it sees the invisible there is no direct cognition and this is the state of nidra which in yoga is called shoonya - nothingness or void. The experience of this shoonya and nidra is also another state of meditation.
After this comes the state of turiya, the state of being completely alert in the total field of consciousness. Alertness means sharpening of all the faculties that are inherent in one's personality, being attentive and ready to move or act in any direction necessary. That is the state of turiya, where the self-luminosity of the chetana tattwa, the totality of consciousness, is experienced, where one is the observer, the drashta, of past, present and future. This is the concept of consciousness and mind in yoga.
Now, the question remains as to how we can develop this mind? Generally, developing the mind means improving one's memory, one's concentration, one's intellectual powers and modes of expression. No doubt, the practices of yoga go a very long way in improving these various manifestations within the mind. However, the concept of developing the mind is again different as per the theory of the mind.
Yoga says that things we express and experience in our day-to-day life in the form of buddhi (intellect), smriti (memory), bhaya (insecurity or fear) and bhavana, (the positive emotions of compassion and love, etc), are different manifestations of chetana tattwa. As you go deeper in spiritual life, developing your personality and consciousness, these different manifestations also become more refined and one is able to express transcendental feeling. The process of expression is just one type of manifestation, it is not final. These different manifestations are called vrittis (mental modifications) and it is here that yogic philosophy begins.
When, in the Yoga Sutras it asks, "What is the aim of yoga?" people say that the aim is to control the vrittis. This is wrong. The aim of yoga is not to control the vrittis. You see, there are two sutras. To the first question, "What is yoga?" Sage Patanjali replied, Atha yoga anushasanam - yoga is a form of discipline. When he was asked, "What is the result of this discipline?" he then replied, Yogaschitta vritta nirodhah - through this discipline you will gain control over the different modifications of chitta. Chitta means the aspect which observes, which sees, which is consciously active in the world. Chitta does not mean the mind, because the vrittis are the mind, and it is the aim of the yogic discipline to alter the vrittis.
The word for discipline in Sanskrit is anushasanam. The word anu means 'atomic', 'the most tiny and subtle'; (you know the nature of an atom; invisible yet potent) and shasanam means 'to rule over' or 'to govern'. So, the concept of discipline in yoga is a process in which we learn to govern the subtlest aspect, the unknown aspect, of our own selves. Therefore, it is very important that we understand the first sutra, Atha yoga anushasanam, properly, because the second and third sutras are just outcomes of this ability to govern or control.
It is here that the concept of developing the mind begins in yoga: change the vrittis, know the vrittis, sublimate the vrittis. It is here in the five major classifications of the vrittis that all the traits of our personality, all the thoughts, desires and actions come, and these five vrittis have not less than a thousand sub-vrittis in each one. Therefore, it is very clearly said that to govern, modify and master the subtlest aspect of our personality from where such units are generated, is the practice of yoga. This is the statement of the first sutra.
Much later in the Yoga Sutras there is another passage which recognises that one needs to follow a particular system or path, in order to have that self-control. To follow that path one needs to have shraddha (conviction), vishwas (belief), ishta (object of faith) and deergaa kal abhyasa (long-term practice).
It is human nature to become bored with something very fast. First there is craving or desire, then there is action, then the result of the action, which in turn produces either satisfaction or dissatisfaction. According to the results, another cycle of desire begins. If that process is stopped one becomes bored very easily. In abhyasa (practice) that happens to many people, because our expectations go faster than the abilities of the body and mind. With expectations there is boredom. In our meditation practices we want to see the light in the very first sitting. Before we begin our meditation, there are mental problems, there is mental conflict, dissatisfaction and a desire to create a change in order to escape from that boredom.
Yoga says that any process which you adopt eventually becomes fruitful. It becomes fruitful when you have the conviction, when you are able to continue with that practice for long periods. Regular daily practice must be maintained. This regularity, this simple discipline, helps to change the pattern of the vrittis. When you are able to change the pattern of the vrittis, the development of mind takes place.