I have a very alternative perspective, especially coming from an applied physics background. I don’t know if anyone has experienced what it is like to be a crab, but I know that there are people who claim to have experienced events from other animals perspective, and hundred of thousands that claim to have done so from other humans' perspective, in near death experiences.

A few years ago I thought that NDEs basically were that they saw a light and felt a bit relaxed perhaps. Some facts, without an attempt at explaining them: The experience is very similar between experiencers and involve numerous distinct steps, and while some people only have a few of the steps, they seem to be largely the same. The step where someone experiences things from another person’s perspective, or in some cases animal’s, is the “life review”. Positive and negative interactions from the (nearly) dying person’s life is replayed and experienced from their own as well as other involved persons’ (or much more rarely, animals’) perspective. These are also relived somewhat in parallell, a common description is that they are “outside time” or that “it’s not in linear time” (Which btw is very similar to what a lot of John E Mack’s abduction clients told him about their abduction experience. Similar brain mechanisms, or similar actual event perhaps.)

NDEs are not uncommon either, estimates are in the hundred of thousands to millions.

So, now if these experiences are actually what was experienced by the other party, it might indicate that qualia are the same for everyone, your red is my red, and so on (Why is it always red?).

Another interesting thing from NDEs is the first step (so before life review mentioned above), which is an out of body experience. A significant percentage report seeing their surrounding, into neighboring rooms at the hospital, and all sides of objects at the same time, as well as 360 degrees around in all directions. Even more interesting is that a majority of blind people in the survey I read, had been able to see, and there are instances where people blind from birth could say which people in the operating room wore the same color clothes, even though they could not name the color. (Also, at another step than the two mentioned here, a large percentage of seeing report percieving new colors that they have not previously seen).

So this is about 2% of the strange things with NDEs, I would probably dismiss it if it wasn’t for the richness (often years of experiences, although time is a difficult concept in NDEs, uniformity and not uncommonly, information gained during them that the experiencer could not have known. Basically I ended up just feeling desperate hanging on to a materialistic world view.

So there are many mentions about a nerve system, or neurons or other things as a basis for consciousness, but we must explain that many NDEs happen on an operating table with no oxygen supply to the brain, sometimes for hours, and to people with almost no brain tissue left.

I won’t try to convince anyone, because I know I could not have convinced 20-30 year old myself of this even if I could convince “him” that I was himself from the future :) And that doesn’t mean I am right either, of course.

As a footnote, experiencing things from other people’s perspective isn’t limited to NDEs, Federico Faggin, the designer of the Intel 4004, describes one that happened to him in traffic. He also has some interesting metaphysical view, that seem to originate in revelations, rather than the kind of reasoning (if you allow me to use that word) here, but are very compatible with (to skip to the conclusion) the idea that consciousness might be fundamental, and spacetime not.