People have found the theory of rebirth in ancient Indian thought problematical in various ways. One of the difficulties of making coherent sense of it is that in some respects the theory is pulling in two different directions, or talking about two different sorts of things. I believe that the reason for this is that we are presented here, not with a single general theory, but with two general theories. (I say 'general', because there are of course also different versions of each theory).
Both theories have some things in common. They are both expressed in physical terms. In both the cause of rebirth is karma, that is to say certain thoughts and actions of a person which function as causes which have effects. Karma is divided into 'good' karma, which broadly means thoughts and acts that promote happiness and welfare, and 'bad' karma, mental states and behaviour that produce unhappiness and do harm. Both theories accept that good or happy karma causes rebirth into happy states, and that bad or unhappy karma causes rebirth into unhappy states. Both theories also accept that these rebirth states are finite in duration. They don't last for ever.
But there are also decisive differences. I suggest that the two theories are: on the one hand what might be called the Popular Moral Justice Theory of Physical Rebirth, and on the other what could be termed the Philosophical Theory of the Unhappiness of Psychological Rebirth. Whatever the connections between them, I shall argue that we have here two distinct ancient Indian theories of rebirth. This is the case both for what became known as the Hindu tradition of the Upanisads, where the theories of rebirth first appear, and for Buddhism which adopted them with some changes.
The Popular Moral Justice Theory of Physical Rebirth
In the popular theory it is the person, or at least part of the person, who is reborn, and the theory is entirely about physical rebirth after physical death.
If a person leads a good life, with karmic thoughts and behaviour that promote happiness and wellbeing, then after the death of her physical body she is born again, either back on earth as a favoured person enjoying good health or beauty or wealth and influence, or as a god in heaven.
If a person leads a bad life, thinking and behaving karmically in a way that causes unhappiness and harm, then following the death of her physical body she is either born again on earth in an unfavourable situation enduring ill health or ugliness or poverty and obscurity, or is reborn in hell where she suffers punishment.
This is a moral justice theory because it states that a good person, who might not be much rewarded in this life, will be rewarded in the next, and a bad person, who may avoid punishment in this life, will be punished in the next.
For this to work it has to be at least part of the person who is reborn. This doesn't mean the whole person composed of both body and mind (nama-rupa), because the body dies. Since what is left is mind or consciousness, what passes to the next life needs to be the person's consciousness of who he is and what he has done. Although he is reborn from being human to being a god, he has to retain enough personal awareness to know that formerly he was a good person who is now being rewarded. Although someone is reborn from being human to becoming a goat, he carries across the awareness that because he was lecherous in his previous life he is now being punished by being turned into a goat.
This popular theory describes what is, at least from the point of view of good people, a satisfactory state of affairs. It is a very familiar idea, that of the universe being so constituted that moral justice is done, if not in this life, then in an afterlife. It is what many people would like to believe, and it is found in one version or another all over the world and at many different historical periods.
The Philosophical Theory of the Unhappiness of Psychological Rebirth
The other ancient Indian theory of rebirth is a more philosophical theory of rebirth and of liberation from it.
Whereas the popular theory presents rebirth as a satisfactory state of affairs, in the philosophical theory all rebirth is seen as an unsatisfactory state of affairs, as a situation of duhkha or unhappiness and suffering. That is one difference between the two theories.
Another is that in the philosophical theory, arising out of this conception of rebirth as an unhappy situation, is the idea of the importance of liberating oneself from rebirth. This concept of liberation has no natural place in the popular theory, where a good person who is due to be rewarded in heaven, has no reason to strive to be so good that he is liberated from rebirth, since this will cancel his reward in heaven. But in the philosophical theory, where rebirth is used as a kind of image of the unsatisfactory nature of human life and consciousness, characterised by unhappiness and suffering, seeking liberation from the unhappiness of rebirth makes obvious sense.
Along with the idea of liberation in the philosophical theory is the belief that this liberation can be achieved in this present life. This leads to the third and last important difference between the philosophical theory and the popular theory. The philosophical theory is typically expressed in physical terms. If we took this literally, then all liberation in this life would involve is that the liberated person, when she died, wouldn't be reborn into any other life. Liberation wouldn't change her in any way in this life, but only change what happened to her after death. However, this isn't at all what the theory states.
Instead it is said that a person achieving liberation in this life from rebirth also brings about a radical change in her present life and consciousness. She perfects herself mentally and ethically. She now enjoys a stable state of wisdom, equanimity and bliss. Consequently at least part of the rebirth this person has been liberated from must be a kind of psychological rebirth in her consciousness from one unstable state of ignorance and emotional attachment and happiness and unhappiness to another. This indicates that in the philosophical theory, rebirth, as well perhaps as being about physical rebirth after physical death, is also an image of the condition of ordinary human consciousness in this life, with its constant round of different moods and circumstances, some happy, some unhappy, but neither lasting for long, especially not happiness. One can easily read the apparent account of physical rebirth in the philosophical theory as poetical images of psychological states. Heaven, a place where everything is agreeable and desires are satisfied, is a natural image of such happy times in this present life, which we are wont to describe as 'heaven on earth'. Hell, a place of unhappiness and suffering, is a straightforward image of times of misery and pain in this present life, periods we typically describe as 'going through hell'. Being reborn to the life of a non-human animal is a familiar image of those times in this present life when we follow unthinking routine and have limited understanding. Karma is also easy to understand as a process of mental cause and effect in everyday consciousness. Whether or not one is convinced by this interpretation of rebirth states, the fact remains that the philosophical theory must at least in part be about psychological rebirth, and this marks a final decisive difference between the philosophical and popular theories. That theory of moral justice is entirely about physical rebirth after physical death. The philosophical theory, by contrast, is at least partly, and to an important degree, about psychological rebirth.
At this point I must just add that the psychological rebirth being talked about here is not the theory of rebirth of momentary conscious states from one instant to the next, which is sometimes found in Buddhism. Rebirth of conscious states is certainly part of the psychology underlying psychological rebirth in the unliberated consciousness. But it is also part of the psychology underlying the liberated state. So rebirth of conscious states is not the psychological rebirth which is brought to an end by liberation in this life. (As we shall see, it is not physical rebirth either).
Why aren't these two theories clearly distinguished from one another in the ancient texts?
I hope I have shown by analysis that there are in fact two related but different theories of rebirth being put forward in the ancient Indian texts. It's quite possible that to begin with they weren't clearly distinguished from one another in the thinking of the sages of the Upanisads who were struggling to bring these new ideas to birth. Also the Upanisadic thinkers were inclined to see correspondences between the cosmos and the human being, including human consciousness. However, over the centuries one might have expected the acute Indian mind to have separated the two theories out. Why didn't this happen?
I don't think it would have been in the interests of the philosophers of rebirth to do this. They would have recognised that both theories were required, and that people needed to be able to move back and forth between them. Everyone learned the popular theory to begin with, and for many people spending their lives working to earn a living and raise a family and with no particular interest in or aptitude for philosophy, it was the theory they stayed with all their life. It was important that the people had this theory to encourage them to lead good lives and be model citizens (and, indeed, endure social hardships without rebellion!) It was from the ranks of the population at large that some emerged who wanted to step aside from ordinary social life, at least for a while, and learn what the philosophers had to say about rebirth, and their idea of liberation from it. These philosophers may well have believed in the popular theory themselves, as well as seeing its social usefulness. But in any case they had nothing to gain by cutting anyone off from that theory, since, apart from anything else, a person seeking philosophical understanding and liberation might well fail in this endeavour, and return to ordinary life. What the philosophers seem to have done, while keeping their public utterances on rebirth clothed in physical language, was to privately introduce the inquirer to the idea that the doctrine of rebirth also had a deeper, poetical meaning.
I think it may have been psychological rebirth that was the original concern of the thinkers of the Upanisads. It is generally recognised that, unlike the earlier Vedas which are concerned more with the external world, the Upanisads turn inwards and focus much more on consciousness. This led the Upanisadic sages to posit the existence of an enduring subject of consciousness, the inner self or atman. This unchanging subject of consciousness was contrasted with consciousness itself which was ever-changing, and also imperfect. Consciousness was characterised by ignorance of the true nature of reality, and by emotional attachment, especially sense desires, which were karma causing human consciousness to pass through a series of transient moods, depending on whether the sense objects were agreeable or disagreeable. I think it may have been out of this interest in human consciousness, the inner human experience of life, that the Upanisadic thinkers developed their idea of the unsatisfactoriness of rebirth. For them liberation involved controlling sense desires, developing emotional equanimity, and gaining understanding of the true nature of reality. In particular this involved direct knowledge of one's inner self or abiding subject of consciousness, the atman, that stayed the same through change, and its identity with the cosmic principle of brahman.
At the same time the thinkers of the Upanisads were still also in the tradition of the Vedas, which had a moral justice theory. This was of only a single rebirth into one everlasting afterlife. The Upanisadic thinkers knew that the ordinary people were inspired by the Vedic idea of a life of goodness on earth being rewarded by joy in an eternal life in heaven, and were consoled by the idea that bad people in this life would be punished for ever in hell after their death. There was a problem with this view, however. Most people are not all good or all bad, but instead are a mixture, sometimes doing good things, but at other times doing bad things. A person who might be only just a little more good than bad enjoys the delights of heaven for ever, whereas a person who is very similar, but just a fraction more bad than good, is punished in hell for eternity. Since most people aren't all good or all bad, why should their single afterlife be all good or all bad?
Here there was a very apt correspondence between the transient nature of karma-caused states of happiness and unhappiness in human life and consciousness, and the happy and unhappy states experienced after death which were also caused by karma. It was an improvement on the old Vedic theory to say that a particular afterlife was also transient, in the sense that it came to an end eventually, and was followed by other afterlives, so that all the karma could take effect. People might have done bad things for which they will be punished in an unhappy life after death, but if they made amends and also did good things, for that they will also be rewarded in a happy life after death. Here the philosophical theory of psychological rebirth could be usefully applied in physical terms to the popular theory to ensure that people got rewarded or punished in future lives in strictly fair proportion to the good or bad they had done in past lives.
Most of the Upanisadic conception of rebirth was taken over by the Buddha. In his theory too there are in fact the two different theories, the popular theory of physical rebirth and the philosophical theory of psychological rebirth, and in the Buddhist tradition too they are treated as though they are just a single doctrine. The Buddha clearly taught the popular theory of moral justice, in which people get their just deserts after death, for example people who are mean in this life being born poor in the next. His acceptance of the popular theory may also have been connected with his tolerance of popular pre-Buddhist religious beliefs among the ordinary people. The Buddha also taught the philosophical theory of the unsatisfactory nature of psychological rebirth, and the importance of gaining liberation from it in this life. The Buddha continued the tradition of recognising the importance of having both theories. Like other Indian philosophers his deepest interest was in the philosophical theory and liberation, but he also, especially having been brought up himself in the governing class, understood the vital role of the moral justice theory in regulating the behaviour of the population at large. To that end he saw more benefit in treating the two theories as two aspects of the one doctrine of rebirth, and no benefit in drawing attention to their differences.
Is the philosophical theory only about psychological rebirth, or is it about physical rebirth as well?
I have argued that the philosophical theory has to be at least in part about psychological rebirth. The question remaining to be considered is whether it is entirely about this, or whether it is also about physical rebirth. To approach an answer to this, we have to look at what a strictly philosophical account of physical rebirth would be, and see if this is what the philosophical theory is actually saying. This needs to be done separately for the Hindu theory of the Upanisads and for the Buddhist theory, because there is an important difference between them.
In the case of the philosophical theory being developed in the Upanisads, what passes from life to life is said to be the atman, which is the subject of consciousness, but not consciousness itself, and which is characterised as being impersonal. If this is taken as an account of physical rebirth, then it means that what survives physical death and takes on a new life is the impersonal atman, which carries none of the person across with it.
This makes this Hindu philosophical theory, taken as a theory of physical rebirth, incompatible with the popular moral justice theory. That theory requires it to be at least part of the consciousness of the person which is reborn, so that the good person of this life knows after his death that he is being rewarded by being reborn as a god in heaven, and so that the bad person of this present life knows following his death that he is being punished by being reborn to suffer in hell. In the philosophical theory of rebirth, taken as a theory of physical rebirth, far from there being this personal justice, there is a situation of injustice. Because the link between this life and the next is impersonal, the good person dies when he physically dies, his conscious states as well as his body, and the next person with his atman who is rewarded in heaven for what the first person did is a different person. The good person isn't rewarded after death. The person in heaven is rewarded for what someone else did. Similarly, the bad person escapes punishment in the next life, and the person suffering in hell is being punished for what someone else did.
The impersonal atman leads to additional problems for the philosophical theory when it is taken as a theory of physical rebirth. For example, it becomes irrelevant that karma only operates on the lives that share the same atman. Since the people with that atman are different people, it could as well be anyone else who unfairly reaps my karma. Having the same atman is redundant. Also, the philosophical theory, if about physical rebirth, says that the liberated person isn't physically reborn. But in fact the next person wouldn't have been that person, but a different person. So what a liberated person achieves after death is ensuring that someone else isn't reborn!
Not only is all this deeply incompatible with the moral justice theory of rebirth, it is also not at all the message that is being put forward in the philosophical theory. Instead this message is that a person experiences the consequences of her own karma, and that becoming liberated means becoming liberated from one's own rebirth. This is reason to think that the Hindu philosophical theory originated in the Upanisads is not in fact meant to be a theory of physical rebirth in addition to being a theory of psychological rebirth. In the case of this theory it looks as if it was only intended to be about psychological rebirth.
In the case of the Buddhist philosophical theory, as well as being a theory of psychological rebirth, it also works better than the Upanisadic theory as a theory of physical rebirth. The Buddha rejected the atman, and in his philosophical theory, taken as in part a theory of physical rebirth, it is the stream of consciousness that passes from one life to the next. The same series of causally connected conscious states continues after the death of the body and becomes the stream of consciousness of a new body. This is not incompatible with the popular theory the way the Hindu theory with the atman is. Since the Buddhist philosophical theory, taken as a theory of physical rebirth, has consciousness as what moves from one life to the next, it allows for the possibility of the degree of personal awareness necessary for the popular theory to be causally passed from one life to the next. It is a happy consequence of the Buddha's rejection of the atman, that the philosophical theory of psychological rebirth, even if it is also taken as a theory of physical rebirth too, is still in principle compatible with the moral justice theory which Buddhism also upholds.
So, in the case of Buddhism, we have the philosophical theory of the unhappiness of psychological rebirth, and we have the popular moral justice theory of physical rebirth with some support from the philosophical theory when that is taken to be about physical rebirth as well as about psychological rebirth.
I have already argued that a third theory of rebirth found in Buddhism, that of the rebirth of momentary conscious states from instant to instant, is not psychological rebirth. I shall now argue that it is not physical rebirth either. Rebirth of conscious states is certainly involved in physical rebirth according to the Buddhist view, because it is this series of conscious states that continues from one life to the next and takes on a new body. Indeed it is the rebirth of conscious states that ensures that it is, to the degree required by the moral justice theory, the person who is reborn. But the physical rebirth that is brought to an end in the case of a liberated person is the rebirth of a new body, not the rebirth of consciousness. It might well be that the rebirth of conscious states ends too, having no body to support it. But this is irrelevant, because if consciousness did in fact continue, so long as it took on no new body, that would still be the end of physical rebirth. So, while the rebirth of conscious states is part of the psychology underlying the Buddhist doctrine of rebirth, it is neither the theory of physical rebirth nor the theory of psychological rebirth which together compose that doctrine.
Conclusion
Despite the fact that the ancient Indian philosophers don't themselves separate the two theories out from one another, and I have suggested reasons why they didn't, I have argued that, on analysis, there turn out to be at least two distinguishable theories in the doctrine of rebirth. When we separate out the popular moral justice theory of physical rebirth from the philosophical theory of psychological rebirth, the whole doctrine of rebirth begins to make a lot more sense. This analysis also renders unnecessary any polarisation of views about the ancient Indian philosophy of rebirth, between those who favour a psychological interpretation, and those who uphold the physical interpretation. Both viewpoints are valid, but neither one of them is the whole truth. The ancient doctrine of rebirth is broad enough and wise enough to include them both.
Back in the 1970s Gerald Dupre wrote a series of articles on Buddhism and science for The Middle Way, journal of the Buddhist Society in London, which were reprinted in a book of essays, and also translated into German. In the 1980s he was founder chairperson of the Scientific Buddhist Association and major contributor to its magazine The Western Buddhist, dedicated to setting out core Buddhist doctrines in clear language, as well as beginning to present Buddhist mental training in easy steps. He then moved away from Buddhism to study philosophy at London University, and continued his studies in this area and that of consciousness for a dozen years. He has retained a great admiration for the ideas of the Buddha, and is now writing new and, he hopes, more philosophically acute articles on this subject.
