The mind is a mix of positive and negative tendencies. Some of which can remain dormant for long periods of time until the right causes and conditions in life occur to activate them. The potential for both good and bad lies dormant in us like karmic seeds. I think from what little I know about biology, DNA works in a similar fashion. We all have strands of inactive DNA which remain dormant until the environment around us changes in such a way that the conditions are ripe to activate it.
When a tadpole becomes a frog. During the different stages of mutation in the biological flow, what is it that transfers from one moment to the next?
What is left of the caterpillar when it becomes a butterfly?
This mysterious flow of life has no discernible beginning, even the Buddha said he could not see the beginning of Samsara, no matter how far back in time he looked he found no beginning to it. We have been entangled in this cycle of birth and death for an incalculable amount of time, becoming different beings over the course of our endless rebirths, playing different roles in this neverending story of self.
The Buddha said that the problematic behaviour that keeps us bound to Samsara springs up from three unwholesome roots: greed, hatred, and delusion. But because we are ignorant of their presence in the mind, these three poisons keep creating problems for us. And until we have properly uprooted them we are a mixed bag of karmic seeds, some of which can lie dormant in us for a considerable length of time, some for as long as lifetimes, waiting for the right conditions to sprout. A moral person can become immoral; and a bad person can become good. Beings can turn, sometimes quite suddenly. Angels can become devils, and devils can become angels.
There's a story in the Buddhist suttas which is a dramatic example of the way people can change suddenly when dormant karma becomes activated. (The story can be read here: Angulimala: A murderer's road to sainthood ) Angulimala went from a peace-loving model student, to a serial killer who tried to make the Buddha his 1000th victim, but after his encounter with the Buddha he became his disciple, and after a period of training Angulimala became a fully enlightened being that wouldn't harm a fly.
This story shows the fluidity of self, that nothing is set in stone, things arise and cease due to the causes and conditions that shape them. This knowledge can bring hope, because it means that we are not completely powerless, we can put in the right conditions to activate the wholesome tendencies of the mind and use those to put a stop to the unwholesome tendencies for good. When the mind is no longer clouded by greed, hatred, and delusion, it naturally becomes light and free, luminous like the moon coming out from behind the clouds.
The self is not what we think, whatever we identify with, that is not the self. The self is not a static entity. It is changing. Each mind moment a new moment of becoming. What went before has gone. We try to make the nice moments last, relive them, preserve them, but looking at a photograph is not the same, there's a kind of sadness with photographs, you see something that has passed, has changed, a moment that no longer exists. If you were to stitch photographs of your life together you would see the way we change from one self to another. We are a flow of energy. What we identify with changes. Our passions change. Everything changes. Even if you preserve a moment, and keep trying to relive the pleasant feelings associated with it, eventually it becomes tiring, one gets bored, this can happen with music, movies, books, video games, relationships, drugs. Our senses grow jaded, and our interests and personalities change, and what once excited us we no longer find interesting. This too is change.
I am a different person than I was when I first sat down to write this, and that moment has now gone, it no longer exists.
We die in every moment. Each tick of the clock is a new self.
Time is change.
There's something exhilarating about knowing that, it feels freeing when one can flow from one moment to the next without clinging to anything. In our day to day life, we do not realise how the sense of self with its identifying, its cares, woes, wants, and resentments weighs us down, we carry this stuff around with us like a concrete block that just gets heavier and heavier to carry, the story of self is tiring and burdensome; but when one lets go of the story. One feels lighter, freer and happier. Time feels different then.