In recent times there has been interest in the congruence of some of the core concepts of buddhism and consciousness studies. Concepts such as impermanence and the lack of a permanent, enduring self have been argued to be consistent with modern findings of neurosicence and physics. It has also been suggested that the methods of introspective investigation and insight utilised in buddhist practices could be useful in developing a first-person methodology for studying consciousness. For instance, in her book "Consciousness: An Introduction", author and consciousness researcher Susan Blackmore devotes a chapter to buddhism and meditation as exemplars of "first person" aproaches to consciousness.
However, one sticking point in the development of a harmonious relationship between buddhism and consciousness research is the issue of rebirth. Belief in rebirth is contended to be incompatible with a scientific worldview. For instance, Stephen Batchelor, an ex monk and popular writer who has written "Buddhism without Beliefs" and "Confession of a Buddhist Atheist" (both of which I highly recommend) argues for a rationally based buddhism consistent with modern science. He argues here that rebirth is a "relic of ancient Indian culture that has attached itself to Buddhism throughout its history, and that is perhaps no longer necessary."
Similarly, Blackmore, who has practised Zen meditation for 25 years and is also known as a prominent skeptic of the paranormal writes that "If human consciousness can really leave the body and operate without a brain then everything we know in neuroscience has to be questioned".
In my view, the views of Blackmore and Batchelor could be argued against on at least two fronts.
Firstly, their position seems more akin to a buddhism based on physicalist beliefs rather than a buddhism without beliefs. Batchelor writes in Connfession of a Buddhist Atheist (p36) that " Given current scientific knowledge of the brain, I did not find it difficult to believe that such an organ was capable of producing thoughts, feelings and perceptions". This seems to reflect a naive faith in physicalism and ignorance about the philosophy of consciousness.
Susan Blackmore, a close follower of Daniel Dennett, is more philosophically grounded in her reflections but, to me at least, evokes a world view in which, to quote Whitehead, " nature is a dull affair, soundless, scentless, colourless; merely the hurrying of material, endlessly, meaninglessly."
Contra Batchelor and Blackmore, I think there is enough philosophical and scientific uncertainty in relation to consciousness to conclude that a secular, skeptical buddhism does not necessarily mean a buddhism based on physicalism.
Secondly, I believe that it is incorrect to assert that a belief in rebirth is necessarily incompatible with a rational and scientific world view. Here are some reasons why:
If a plausible form of panexperientialism is that which posits a universal, cosmic subject (as previously discussed here and here)then, by analogy with human experience, it is reasonable to assume that such a cosmic subject would in some sense retain previous experiences through memory. It is also reasonable to assume that the memories of the cosmic subject from the life cycle of one organism could potentially influence, be recalled by, or be passed on to other organisms.
Therefore, it seems to me that if panexperientialism is a plausible explanation of consciousness then it is also plausible that rebirth happens. Of course, this does not show that rebirth does occur, only that it plausibly could.
So, if one accepts that rebirth could be the case, why does this matter?
There are many implications, but here are just a couple:
Firstly, it means that claims of empirical evidence of rebirth are worthy of being taken seriously. For example, the work of Ian Stevenson may be worthy of close scrutiny. I have not assessed in much depth any of the purported evidence he has collected so am not in a position to comment on this.
Secondly, it means that a secular based buddhism (by which I suppose I mean one that is devoid of religious superstitions) need not necessarily disregard claims of rebirth. After all, if we respect the insights into consciousness of those such as the Buddha, then it is not very consistent to ignore or "bracket" important aspects of what they had to say.
In this respect it seems to me that insights into rebirth are a highly relevant aspect of many of those who have ventured into the deepest and most profound realms of consciousness. For example, the Pali Canon, the earliest written Buddhist scriptures, frequently records the Buddha recollecting past lives in deep state of meditation, such as here :
"When the mind was thus concentrated, purified, bright, unblemished, rid of defilement, pliant, malleable, steady, & attained to imperturbability, I directed it to the knowledge of recollecting my past lives."
Contemporary contemplatives, such as Ajahn Brahm also report recollection of past lives being an intrinsic part of deep meditation:
"When the memory of your own birth appears, it is just like you are there and you experience all feelings of that birth. Then you can ask yourself for an even earlier memory, and then you get back into your past lives."
So a sympathetic view of rebirth I think allows a more consistent and integrated reading of the teachings of those such as the Buddha.
As an aside however, regardless of the rationality of the concept of rebirth, from another angle I think there is some merit in the view that the illusory, transient and empty nature of the "I" means that the question of rebirth is by and large irrelevant. As Buddhadasa, another senior monk from the Thai Forest tradition, puts it:
"There is just a feeling of "I" and "mine" arising due to the foolishness whereby one is deluded by the beguiling nature of sense-experience. Therefore, there being no one born here, there is no one who dies and is reborn. So, the whole question of rebirth is utterly foolish and nothing to do with Buddhism at all."
To me, perhaps the most significant thing is that, whether or not one believes in rebirth, panexperientialism opens up the opportunity for a secular buddhism that is not only free of superstition but also frees the world of the sterility and lifelessnes of physicalism.
But to return to the primary topic of this post, I think it can be concluded that a belief in rebirth is not necessarily irrational or inconsistent with a logical, scientifically informed view of the world.