What is karma? Karma means action, and it is classified into three categories: āgāmya, sañcita and prārabdha. Āgāmya means fresh action that we do of our own free will, and such action bears fruit, which we must later experience. Sañcita is the store of all the fruits of our past karmas that we have not yet experienced, and prārabdha is that portion of our sañcita that has been selected for us to experience in this lifetime.
For whom is all this karma? Who is it who does āgāmya, and who then experiences the resulting prārabdha? It is only ourself as this ego. In sleep we do not rise as this ego, so we then do not do any karma or experience any fruit. But as soon as we (this ego) wake from sleep or begin to dream, we start doing karma and experiencing the fruit of our past karmas. Therefore there is no karma without our ego, so our ego is the root and foundation of all karma.
However much we may try to cut a tree, so long as its root survives it will continue sprouting again and again. Likewise, so long as our ego, the root of all karma, survives, we cannot destroy our karma. The only way to destroy karma is to destroy our ego.
What is this ego? Is it real? This ego is what we now seem to be, but it is not what we really are. It is like an illusory snake. What seems to be a snake is actually only a rope. So long as we mistake the rope to be a snake, we do not see any rope but only a snake. But if we look at the snake very carefully, we will see that it is actually just a rope, and then we will no longer mistake it to be a snake.
Likewise, what now seems to be this ego is actually only ourself. So long as we mistake ourself to be this ego, we do not see ourself as we really are but instead see ourself only as this ego. But if we look at this ego very carefully, we will see that it is actually just the infinite self-awareness that we really are, and then we will no longer mistake ourself to be this ego.
Looking at ourself or our ego very carefully is what is called ātma-vicāra or self-investigation. Since we are not really this ego, if we persevere in investigating ourself (observing our ego very carefully) until we see what we really are, this illusion called ‘ego’ will cease to exist, and when it ceases to exist all its karma will also cease to exist.
Therefore investigating ourself or meditating on ‘I’, our ego, is the one infallible means to destroy all karma. Indeed, it is the only mean by which we can destroy it, because it is the only means by which we can destroy the illusion that we are this finite thing called ‘ego’.
Since everything that we experience is the fruit of our past karmas, and since the root of all karma and its fruit is only our own ego, this simple path of self-investigation taught to us by Bhagavan Ramana is the solution to all the problems we face and all the problems we could ever face. Indeed according to him it is the solution to all the problems of the world, because the world and its problems seem to exist only in the view of our ego (just as any world or problems that we see in a dream seem to exist only in the view of our dreaming mind), so when our ego is destroyed by self-investigation, this world and all its problems will also cease to exist, and what will then remain is what alone is real, namely ourself, the one infinite and blissful space of pure self-awareness.