Evidence can be a problematic term in Buddhism. Who is it that determines how much evidence is required, that is, the strength of evidence? This is what we need to know because he who sets the strength of evidence can make the amount of evidence required almost impossible to achieve. For example, if I claim that the Buddha did not deny the ātman or in Pali, attā because to do so would make him an annihilationist, which he denied being, the evidence is pretty straightforward in the Ānanda Sutta (SN 44:10). For those who presuppose that the Buddha did, in fact, deny the ātman, no amount of evidence or reason will suffice. At this juncture we can become deceived—Buddhism turned into something it isn't.
When it comes to what can be described as a secular Buddhist book, Stephen Batchelor’s book, Buddhism Without Beliefs, a national bestseller, does not provide any evidence for his theory about Buddhism. What he gives the reader is more of a proposal for a theory. He makes his appeal to a particular segment of the Buddhist population who finds the Buddhist tenets of karma, rebirth and even nirvana troubling if not hard to swallow. He tells the reader that karma is basically “intention”. He doesn’t mention that the Buddha also told his monks,
“Bhikkhus, this body is not yours, nor does it belong to others. It is old kamma [karma], to be seen as generated and fashioned by volition, as something to be felt” (SN 12:37).
There is a lot to unpack here but the book, as I mentioned before, is more of a proposal about Buddhism and what it should be. It is not based on evidence. So, how does Batchelor treat “rebirth”?
“Such a deep-seated sense of personal identity is a fiction, a tragic habit that lies at the root of craving and anguish. How do we square this with rebirth, which necessarily entails the existence of something that not only survives the death of the body and brain but somehow traverses the space between a corpse and a fertilized ovum?”
Based upon his proposal of what he would like Buddhism to be, there is no way to resolve the matter of rebirth since Batchelor believes there is no transmigrant, self or soul. But wait a minute! According to Rune E. A. Johansson,
“We know that nibbāna was the end of rebirth and that the medium of rebirth was viññāṇa, the stream of conscious processes. Now, in nibbāna viññāṇa is said to “stop,” and thereby the kammic [karma] process, carried by it, also stops, and this is the end of rebirth” (The Psychology of Nirvana, p. 105).
Johansson has certainly given us some evidence as to what continues after our death and transmigrates, unlike Batchelor who is proposing his own version of Buddhism in which rebirth can be set aside if you are uncomfortable with it.
So what does Batchelor propose nirvana to be? Not much is the simplest answer. He says:
“We could decide simply to remain absorbed in the mysterious, unformed,- free-play of reality. This would be the choice of the mystic who seeks to extinguish himself in God or Nirvana—analogous perhaps to the tendency among artists to obliterate themselves with alcohol or opiates. But if we value our participation in a shared reality in which it makes sense to make sense, then such self-abnegation would deny a central element of our humanity; the need to speak and act, to share our experience with others.”
So nirvana is no big deal—sort of like dying from a heroin overdose. In fact, nirvana seems to conflict with our humanity which is the need to share our life experiences with others. But according to the Buddha:
“Being unagitated, in the very self (paccattam) he attains complete Nirvana (parinibbayati). Cut off is rebirth, the holy Brahma faring has been lived, what had to be done has been done, there is no more for this state of being” (S. iii. 53-54).
Nirvana, as we can see, gives deeply personal value and meaning to our life which before nirvana seemed meaningless. Nirvana reveals a higher life that transcends our former life, freeing us from future rebirths. Without nirvana, life has little or no real meaning in the long run except to repeat itself infinitely with infinite deaths and rebirths.