Kūṭastha forms the individual soul of a jīva and Indriya-s are classified into two types - jñānendriya-s (organs of perception or knowledge – ears, skin, biological eyes, tongue and nose) and karmendriya-s (organs of action – mouth, hands, legs, organs of procreation and excretion). These five organs are important for normal existence. Mouth/tongue falls under both classification. Nine openings, known as navadvāra – two eyes, two years, two nostrils, mouth, and organs of procreation and excretion come under the category of indriya-s. There is one more opening at the top of the head known as brahmarandhra, which is not a subject of discussion here, through which Kūṭastha (soul) exists at the time of death. These ten, jñānendriya-s and karmendriya-s are external in nature. But there is one thing called antaḥkaraṇa, which is far more powerful than these external organs and external organs are under the direct command of antaḥkaraṇa. This is called internal organ, explained as the seat of thought and feeling, the mind, the thinking faculty, the heart, the conscience, the soul (kūṭastha).
Antaḥkaraṇa consists of mind, intellect, consciousness and ego. All pains and pleasures originate from antaḥkaraṇa and are experienced in both in mind and physical body. It is through the mind that one sees; every type of duality, desire, attachment, lust, etc. originate from the mind. What is mind? Desire, resolve, doubt, faith and faithlessness, steadiness and unsteadiness, shame, intelligence and ignorance, fear and bravery and all such dualities are nothing but the mind. As already discussed, that ultimate realization of the Self happens only in the mind. Mind is not a gross organ like indriya-s. But all these organs are controlled only by the mind. Hence, Kṛṣṇa says in Bhagavad Gītā that mind, along with senses leave the body at the time of death. Kaṭha Upaniṣad also says “Superior to sense organs is tanmātra-s (śabda, sparśa, rūpa, rasa and gandha) and superior to tanmātra-s is the mind.” Mind has attributes; for example, mistaking rope for a snake.
When the mind is active, it is associated with sensory organs. In deep sleep, mind is inactive and we do not perceive anything. Mind acts due to the illumination provided by consciousness (citta), one of the components of antaḥkaraṇa. Mind is the reason for comprehending. The mind is that modification of the internal instrument (antaḥkaraṇa), which considers pros and cons of a subject or saṅkalpa (conception or idea or notion formed in the mind) or vikalpa (alternative, option). Therefore, in order to perceive an object, we need three – mind, sensory organ (such as eyes or ears) and an object to see. According to Advaita Philosophy, when an organ perceives an object, the mind transforms into that object. When eye sees a pot, the mind projects itself as that pot. Now, we can understand why realization can take place only in the mind. It is important to know that the mind is the reason for causing all types of dualities.
Mind by nature is always attracted to sensory inputs. An idle mind cannot remain quiet. It is waiting for some sensory inputs, to construct thought processes, which in turn lead to desires, attachments, etc. When desire is not fulfilled, it transforms into impressions and induces the mind to fulfil the desire at any cost. This is the point where a man’s quality is determined. A person with a fragile mind goes after the desired object at any cost and in the process transforms himself as a completely materialistic person. Materialistic life and spiritual life cannot go together, though material life is the foundation for spiritual life. Without earnings, how can one survive? Spiritual unfoldment happens only in the mind and therefore, the mind has to be devoid of any impressions. These impressions are also known as impurities. The mind functions not merely on the impressions of objects on the gross level, but also functions on the impressions of the subconscious mind on the subtle level. It is always easier to deal with the mind at gross level than at the subtle level. Mind cannot be controlled automatically and there has to be a serious and sincere attempt to subjugate the mind. It has to be controlled consciously. Ultimately, one has to transcend his mind to realize the true concept of non-dualism, wherein all discriminations are rejected.
Patañjali in his Yoga Sūtra (II.28) says, “By the practice of different parts of yoga, the impurities are being destroyed, knowledge becomes effulgent up to discrimination.” Therefore, mind can be purified by constant practice. Practice here means retraction and withdrawal of mind from thought processes. When one does not have desires and attachments, there cannot be any thoughts.
Mind is nothing but convolution of consciousness. Consciousness is always pure, whereas the mind is afflicted by perception. Mind goes after material things and thus is influenced by desires and attachments. When the mind is purged of all afflictions, as a natural process, one realizes the purest form of consciousness, which is nothing but Brahman. Mind always needs something to chew upon. If we fix our concentration on material world, mind remains in wilderness. The more and more we have desires and attachments, the mind tends to be more active, causing serious obstruction in realising consciousness, from which mind gets illumination. Mind is like clouds, obstructing the clear sky above, which can be compared to consciousness. Mind by default is subject to discrimination. As we know, there are three stages of consciousness – active, dream and deep sleep stages. What we dream in our dream state, no longer exists in our active state and during deep sleep state the mind is annihilated and purest consciousness alone prevails. In a perfect meditation also, the mind is dissolved and purest form of consciousness is revealed and this is known as Self-realization.