We have a general understanding of what constitutes knowledge. But philosophers and thinkers of the past studied the nature and the scope of knowledge in detail. They have raised questions like what is knowledge, what is knowable, what is unknowable, and what is the extent to which knowledge is applicable. One of the most famous questions of the Upanishads is: "What is that, knowing which, everything else is known?" (Mundaka Upanishad 1.1.3). The technical term for the study of knowledge, its characteristics and its limitations is "epistemology". In ancient India, nyaya - one of the six classical schools of philosophy - dealt primarily with epistemology (and so did many of the Upanishads).
In the Indian tradition, knowledge was always given a prime slot. It was also agreed that true knowledge lies within and one need not depend on external agencies to gain it. Lord Krishna puts it succinctly in the Bhagavad Gita (4.38) - "Nothing is as pure as knowledge in this world. One who reaches perfection by yoga will eventually find it within."
In a previous article, I wrote how the meaning of science was much broader in the earlier days. Our ancient shastras covered several bodies of knowledge, not just restricted to what we call science today. That is possibly one of the reasons a conflict between science and religion hardly existed in ancient India.
Also read - How ancient India explored knowledge through nyaya
Another reason for the harmonious existence of different systems of knowledge was the framework of the three epistemologies given in the Upanishads. Knowledge is said to be at three levels or three realms. The first is called adhibhuta - the knowledge that belongs to the material world, or what we call "facts". A large part of modern science will come under this heading. The knowledge of the characteristics of a material, evolution of a species, chemical reactions in the human brain, measurement of space and time - all these are parts of adhibhuta.
The second is called adhidaiva - the knowledge that belongs to the non-material sphere, such as emotions, ideas, and beliefs, or what we call "values". Religious faiths, human feelings, and theoretical ideas come under this heading. The emotional response to a work of art, belief in a god or a religious tenet, or an abstract idea conceived by the mind - all these are parts of adhidaiva. While it may be true that the physical manifestation of a human emotion is the chemical reaction in the human brain, the pure emotion aspect belongs to the second realm, or adhidaiva.
The third realm is called adhyatma - the knowledge that belongs to the self, such as personal experiences and insights. Inner awareness and consciousness come under this heading.
While adhibhuta works in the realm of matter (and is realised by experimentation and logic), adhidaiva works in the realm of human psyche (and is realised by faith and imagination), and adhyatma works in the realm of the self (and is realised by experience and wisdom). All these three realms are essential for living a complete human life. And each realm gives us a fresh layer of meaning.
Let me take a Bollywood example to illustrate the three layers of meaning. In the song "Main Hoon Don" (the one picturised on Shah Rukh Khan), we find the line -
Dushman jo mera ho, rehta nahi duniya mein
(One who becomes my enemy, doesn't remain in this world)
If we look at this line from a straightforward, adhibhuta perspective, then the meaning simply becomes that Don would physically kill his enemies, and hence they don't remain in this world. But what if we looked at it poetically? The adhidaiva perspective might give another meaning - Don would befriend his enemies so that they don't remain enemies anymore. Thus the enemies are destroyed because enmity is destroyed. Now, what if we looked at it philosophically? There is no "other" to become an enemy and it is a destruction of the fundamental duality that leads to the state of having no enemies because there is only "one".
Also read - How to fit Bhagavad Gita in 18 tweets
Of course, the lyricist meant the line to apply solely to the material world, but with this framework, it becomes possible to interpret the same thing in different ways, appropriate to the occasion. This framework also helps in giving us an approach that is suitable to the text we read.
For example, if we are reading a text like Surya Siddhanta, an ancient treatise on astronomy, we will deal with it at a physical, material level. If we are reading a text like Natyashastra, an ancient treatise on drama, dance, and music, we will bring in the emotional and imaginative aspects in addition to the physical level. If we are reading one of the Puranas, we will totally keep out the physical level and enjoy it at the level of art. We might also bring in the aspect of consciousness, for the Puranas deal with philosophy at some level. However, if we are reading a purely philosophical text like Yoga Vasishta, we will deal with it wholly at the level of the self.
This framework can be extended not just to our reading but also to various activities we undertake in our daily lives. Some activities are merely at the level of adhibhuta, like taking care of the body or managing finances. Activities like prayer or engagement with an art form will be at the level of adhidaiva. And those activities that involve contemplation and meditation are at the level of adhyatma.
With the existence of these three epistemologies, Hinduism, in traditional times, rarely saw clashes between religion and science, art and science, religion and morals, art and ethics. They realised that truths can be at different levels, applicable to different realms. This is also why Hinduism can quite easily accept another religion or a new mode of thinking in science. Perhaps this is why a Hindu is naturally tolerant and magnanimous. It is a part of her DNA!