(9.150) Living beings are like objects in a dream
For, when analyzed, they have no ultimate identity, just like a rainbow.
Thus, in that they both lack true existence, there is no difference
Between nirvana, the state beyond sorrow, and samsara, the state of sorrow.
Shantideva is telling us we have no fixed identity. We have no identity, so we need to stop believing we have one. We ourselves are empty. Our samsara is empty. Nirvana too is empty. Therefore, we can come to abide in nirvana. Because we ourselves, samsara and nirvana all lack true existence, we can change from a being abiding in samsara to a being abiding in nirvana. Wonderful!
Nagarjuna says for those who emptiness is impossible, nothing is possible; but for those who emptiness is possible, everything is possible. At present, we grasp at ourselves as being fixed, unchanging, and inherently the person we are today. We hear in popular psychology all of the time we need to be our true self, our authentic self. We tell our children to be who they really are. This always leads to a good deal of confusion amongst kids as they ask themselves the question, well who am I really? They then go searching thinking there must be some inherently them that they are that they need to try and embody. All of this is wrong.
We are who we choose to become. For example, we can decide to impute our I on being a good person. When we do this, we naturally come to embody what a good person would be like. We quite literally become a good person. We see this with professions, when people make decisions to become a doctor, a lawyer, an engineer, a salesperson and so forth. They then say they want to be a good doctor or lawyer, and so they try act in those ways. In exactly the same way, we can decide we want to become a Buddha. Indeed, we can change the basis of imputation of our I from an ordinary being to that of a Buddha. With enough familiarity, this could become our living experience.
From a tantric perspective, we can reinterpret popular psychology talking about identifying with our true self or our authentic self by saying that our authentic self is our Buddha nature. Our Buddha nature is our true self, and the wish to attain renunciation is the wish to free our true self from the prison of our false self created by our self-grasping ignorance. The wish to attain enlightenment is the wish to fully unleash our true self to be of the greatest benefit possible to others. What is the nature of our true self, our Buddha nature? It is our very subtle wind and are very subtle mind. These are our continuously residing body and mind that go with us from life to life. It is our continuously residing body in mind that will eventually transform into the body and mind of a Buddha. It is incorrect to say that it is already a Buddha, but it is correct to say that our very subtle body and mind are the substantial causes that will later transform into the body and mind of a Buddha. There is no inherently existent true self, but there is something that goes with us from life to life and will remain with us forever. The question is whether our true self remains merely a potential or whether we fully actualize it by becoming an enlightened being ourselves. With this understanding, we can agree with people who ascribe to modern psychological theories and merely understand those theories in a more Buddhist way.
We often say that there are five principal aspects of the path: renunciation, bodhichitta, the correct view of emptiness, generation stage, and completion stage. How can we understand how all of these fit together? In reality, there is only one activity on the path, namely changing the basis of imputation of our I from an ordinary samsaric being to a fully enlightened Buddha. There are two reasons why we change the basis of imputation of our I, namely for the sake of ourselves (or renunciation), or for the sake of others (or bodhichitta). There are two levels at which we change the basis of imputation of our I, gross and subtle. At a gross level, we changed the basis of imputation of our I to the gross deity body through the practice of generation stage. And at a subtle level, we change the basis of imputation of our I to the subtle deity body through the practice of completion stage. All of this is possible because our I, our body, and our mind are all empty of inherent existence. We are not fixed or permanently attached to our ordinary body and mind. We can choose the body and mind we wish to have as the basis of imputation for our I. It will take training, it will take persistent effort, it will take time, but it is possible.
We see how we change the basis of imputation of our I throughout our life. We start out as a baby, we later become a teenager, then later become a young adult, then middle aged, then an older person. In our previous lives, we imputed our I on completely different bodies and minds. Our I is nothing more than a post-it that we can place on anything. Some bases are beneficial and some are harmful. But the choice is ours. And we clearly see the emptiness of our I, then we realize we can quite literally construct an entirely new pure identity and become a Buddha.