There are many perspectives to understand the Bhagavad Gita. Once one perspective is understood, all other perspectives are understood as they are interconnected. Understanding the senses is one such perspective. The first few verses (2.11-2.30) of the Bhagavad Gita introduce three fundamental concepts. These are senses (indriya) and sense objects, manifested (vyakta) and unmanifested (avyakta), and polarities (dwandwa) . Subsequent verses dwell on various aspects of these issues in depth.

While explaining the kshetra (field) and kshetrajna (knower of the field), Krishna refers to the physical body (shariram) as kshetra (field). He says, “Succinctly described, the kshetra and its modifications are composed of the fundamental elements (fire, air, water, earth and space), ahankaar, intellect (buddhi) , unmanifested (avyakta), ten indiya (senses), mind and the five objects of the senses (13.6) and desire, hatred, pleasure, pain, assemblage (material body), consciousness (chetana) and persistence” (13.7). The ten senses are five organs of perception (jnana-indriya) -eyes, ears, nose, tongue and skin and five organs of action (karma-indriya) -hands, legs, speech, generative organ and organ of defecation.

Jnana-indriya receives external stimuli and feeds the brain on a moment-to-moment basis. Whereas karma-indriya are responsible for actions (karma) performed by us. In another context, Krishna refers to karma-indriya as the instrument of action, which is one of the three constituents of action, the others being the act itself and the doer (18.18). The context of the Gita suggests that whenever senses are described, the reference is to jnana-indriya.

Each sense has a corresponding sense object. The eye responds to light, the ear to sound, the skin to touch, the nose to smell, and the tongue to taste. Gita refers to sense objects or indriya-vishay on many occasions. These include issues such as the consequences of the interaction between the senses and sense objects, and how awareness helps us to maintain a distinction between them.

Each sense has two parts. One is the external and the other is the internal part of the brain. For example, the eyeball represents the external part, and that part of the brain which processes the inputs brought by the external part can be called the controller part of the sense.

The outer part automatically responds to the respective sense object. For example, the earlobes respond to sounds but have no control over which sounds to respond to or ignore. Similarly, the eyeball absorbs all the visible light in front of it. The nose automatically smells.

The external organs of the senses are subject to physical limitations. The eyeball can process certain frequencies of light, which are called visible light, which is a small portion of the entire spectrum of light. That’s why we need X-ray machines, infrared cameras to help us perceive the world from a different perspective. Similarly, the eyeball requires some minimum amount of light to function. This indicates that each sense needs a minimum intensity of its respective sense object to respond.

Coming to the internal part, it is the controller part in the brain that processes the inputs brought by the respective physical part of the sense. While the outer part functions fairly automatically, the controller part is equipped with intelligence. It is capable of separating and choosing the inputs brought by the external parts. This is called cognitive bias in modern science. Krishna beautifully explains this controller part and says, “Sense objects fall away from the abstinent person, but not ras (longing) and longing ceases only when one realises the supreme” (2.59). This longing or attachment is the hallmark of the controller part.

All the combination of controller parts of the senses is nothing but what is known as the mind. While the mind is responsible for immediate decisions like fight or flight, a more refined version of the mind is called intellect (buddhi) , which is responsible for thoughtful actions. The mind is quick, intuitive, responds automatically to sensory inputs and is usually unconscious. Intellect is slow, effortful, analytical, aware and conscious. That’s why Krishna asks to use intellect where the mind is unable to handle, as intellect is superior to the mind (3.42).

Physiologically, the mind and intellect reside in the brain. The brain is an organ which has about 100 billion neurons. It is said that neurons that fire together wire together. These neurons are hardwired regularly during our lifetime. This slow process of hardwiring makes the brain efficient and reduces the energy requirements. In this sense, the brain regularly changes itself, which is called neuroplasticity.

For example, we find driving difficult on the first day and slowly get used to it. This is because of the hardwiring of the neurons, which takes care of the automatic functions involved in driving. Similarly, when we are learning a language or learning to walk as babies, the same hardwiring makes these complex tasks easier for us. Skills acquired through hardwiring stay with us till the end of life.

On the other hand, hardwiring makes things difficult for us. During our childhood, we were hard-wired about various aspects of life. Our families and society carry belief systems that they inherited. They get imprinted on us when we are in formative years, where our ability to distinguish what is right and wrong is at its lowest. This makes us divisive, where we find it difficult to accept others’ points of view.

It is nearly impossible to break the hardwiring. As the brain can change itself, we can form new connections and new hardwiring. This process will help us to override previous connections or bypass them to wean away their divisive qualities, some of which are responsible for our misery. That’s why Krishna encourages us to begin a journey and assures that small efforts bring big gains (2.40). A small effort can help to break old patterns using the brain’s remarkable ability to change itself.

(The writer K. Siva Prasad is a senior IAS officer in the Punjab Government.)