There’s an interesting piece in the Irish Times today about the experiences of people who have survived comas (as well as the experiences of their relatives).
I suppose there are two ways you can interpret the experience of say, finding oneself at one end of a tunnel of light, coupled with a sensation of being drawn upwards towards the waiting arms of one’s deceased relatives. It might be that you veridically experience your soul being called to join theirs in some kind of afterlife. Or it might be that deprivation of oxygen (or some other condition) causes your brain to randomly hallucinate, compiling images and memories from your life into some kind of unified experience as of e.g. being at the end of a tunnel of light etc.
It speaks to the evidential value of a near-death experience. Or calls it into question. I have no doubt that if I underwent such an experience it would be utterly convincing for me, but then surely hallucinations are convincing too. It’s only because they don’t tally with the rest of our experience that we have reason to doubt them. If I saw a pink elephant in my living room, I might recognise it as a hallucination only because it’s so improbable. A near-death experience presents itself as veridical, but it cannot be self-validating. A tunnel of light (etc.) is not as improbable as an elephant in an otherwise normal living room, so you’d have nothing in your experience telling you it cannot be real. You’d take it to be genuine, but that wouldn’t make it genuine.
If physicalism about the mind is true, ultimately all our beliefs and experiences are physical states of the mind. This raises the possibility that there might be other ways of inducing a belief in someone than leading them through a chain of reasoning. Well, of course there are other ways of producing beliefs or else propaganda wouldn’t have a point. But I’m thinking of purely physical processes that engage only the brain considered as a purely physical thing. It might be a matter of giving someone a pill, or it might be a more complicated sort of procedure like having them fast for a week and then meditate under an ice-cold waterfall. Furthermore, imagine that a certain physical procedure was quite reliable, inducing the belief in 9 out of 10 people undergoing it. Imagine the belief is a feeling of oneness with the universe.
If the physical method for producing the belief is reliable, is it just a prejudice to prefer the method of ratiocination? I find this question discomfiting. But maybe it is preferable because it relates the end belief to others that corroborate it. No belief is self-validating. The mystic’s experience of oneness with the universe might be a veridical perception but it might also be a hallucination brought on by mortifying the body. On the other hand, a belief in one’s oneness with the universe that was based on argument would rest on supporting beliefs.