It is a common part of Buddhist belief that we have past lives. I don't want to focus so much on the truth of this, in an objective, testable sense; but on the philosophical senses in which the idea of past lives may help us.
WHAT MANY BUDDHISTS BELIEVE
Much Buddhism is based around a concept that we are always learning lessons. This learning, goes the story, extends across different lifetimes, so that we are always trying to learn enough to get out of one kind of life, and into another. If we learn enough to achieve great insight, and if we manage to gain mastery over ourselves by learning to manage our own desires, then we become free of the need to re-live lives in which lack of insight, and unmanaged desire, cause so much suffering.
If you think of your life as a chance to learn a lesson, I bet you'll be able to think of some stories you are endlessly repeating. It might be the constant re-living of one type of love affair; or the constant succumbing to addiction; or a constant tendency to become angry and take it out on others, thereby ruining your own life as well as theirs. These are the kinds of stories that many Buddhists believe started long before you were born, and will go on long after you are dead. In that sense, your life is simply a station along the path, a place where the old battles can be re-fought. Until the lesson is learned, the suffering will continue.
Furthermore, some of your suffering, so the story goes, is because of things done wrong in lives before your own. So some things that you suffer are not, in an individualistic sense, your own fault; they are the consequence of bad actions done before the 'you' you know came into existence.
From an individualistic point of view (the Western world tends to like to seal cause and consequence inside the life of a single individual), this is anathema. Our version of 'karma' is the kind of justice that is served during one lifetime. We have lost, perhaps, the sense that consequences linger. You can find it in some places - for instance, in the view that white people should be aware of the legacy of slavery; and in the view that men should be aware of the legacy of the suppression of women's rights. But even here, many counter with the view that the past is the past.
TECHNICAL DIFFICULTIES WITH THE LITERAL CONCEPT OF PAST LIVES
There are a few intellectual problems arising, if one is tempted to think of reincarnation as a kind of unbroken chain of past lives. The two main ones perhaps, are represented by the two questions:
1. How do we deal with overlaps? Are we seriously saying that exactly when one death happens, a corresponding birth happens?
2. How do we deal with population numbers? If there were once only a few people, then how can we handle multiplication?
This type of problem tends to arise whenever a religion asserts a truth that conflicts with an intuitive understanding of nature. Theological tracts then get written retrospectively justifying the assertion, which I don't plan to get into here. I am more interested in the benefits of an idea of past lives.
A POTENTIAL BENEFIT OF PAST-LIFE-STYLE THINKING
I would like to suggest we redefine our terminology, and talk in terms of STORIES. And I would like to make a suggestion. The next time you find yourself suffering, particularly in a relationship, I would like you to ask yourself what story it is that you are repeating. My intention is that, by seeing a story we are repeating, we can gain insight, and therefore free ourselves from the need to repeat. It is a similar concept to that used by many psychodynamic counselling practitioners, who would hold that we repeat stories unless and until until we find a way to 'break the chains', as it were.
THE IMPORTANCE OF MYTH
I would also like you to enlist your creativity. Many Buddhist texts have Buddha and others coming up with a story about past lives, to provide information about a current piece of suffering. In this way, someone might present with a problem, and a wise person might use a past story to explain what is being re-lived, using characters recognisable to the listener.
So here's an exercise:
1. Think of something that is causing you pain at the moment. A person, a relationship, a situation.
2. Try to imagine what kind of story, set in the past, you might be re-living.
3. Flesh it out. Name the characters. Give them personalities, virtues and faults.
To offer an example from my own life. I was thinking the other day, of a situation I often find myself in. Without going into detail, I realised that a lot of suffering was caused by my impatient inability to listen to others. So I might have ideas as follows:
1. I am causing pain to others because of my inability to listen without interrupting and shaping what the other person is saying.
2. Maybe, once upon a time, there was a bird who lived by a tree full of berries. The problem was, the berries had thorns protecting them, and the bird could not reach the berries to eat. Whenever other birds came by, he would chase them away, saying 'I'm the owner of this tree! I'm the one who has a right to eat the berries! Go away and leave it to me!' Eventually, the bird died of starvation. Once he was dead, the other birds learned collaboration, letting the smaller ones go in among the thorns, and pass the berries to the larger birds outside.
3. In this way, I might come to realise that I am living out this myth. I am a 'reincarnation' of the big bird who has not learned his lesson, and thinks that he alone can find truth, or food, or whatever. I am chasing away those who could help me, constantly interrupting them in their bids to discover things that would actually help me, if I just let them investigate and collaborate.
Now that I have fleshed out the story, I am able to imagine how I could behave differently, and literally save my life. I can work to allow others, with different characters and abilities to my own, to show me collaboration and difference, so that, together, we can achieve what I alone cannot. What a great lesson! And by fleshing out the story, I have made for myself a myth it is hard to forget. You never know, I might even learn the lesson that needs learning. I might see these situations coming, and learn the habit of backing off and letting others speak and act.
The idea of past lives is rejected by many as silly. But perhaps, if we take a creative approach to the idea of cause and consequence in our lives, then we can accelerate our learning, and our ability to master ourselves and our behaviour. Maybe if we observe some suffering, we can let our imagination come to an understanding of a past life in which that story happened in relatable form. If so, it can become a myth, or a kind of 'morality tale', which we can invest in, and use to prevent ourselves falling into the same old traps.
What stories of suffering are you repeating? How would you name and flesh out the characters involved? How might you respond differently, given your new knowledge of yourself?