He likened Alexander's experience to a DMT trip and thus suggested that brain chemistry was the source of the experience. I'm not saying that's not a valid point.
do you disagree with his point? Is that not a plausible if not the most plausible explanation? you don't have to explain every uttered sentence in a scientific discussion. The most plausible explanations need little to no evidence. The more extraordinary claims need more evidence.
In this case, Harris is making an incredibly weak claim. He doesn't have to show why his explanation is correct; it's Alexander that has all the work in front of him because his claims are extraordinary.
But this claim simply cannot be tested or proved.
That's correct. Harris can't prove his explanation must be the correct one, but, and for the hundredth time, he doesn't have to. he is saying Alexander's explanation doesn't make sense for two reasons (and therefore you should default to the more plausible one). The claim that Alexander's brain was entirely shut down lacks sufficient evidence, and even if it were true his brain is functioning now and he can't reasonably claim that the experiences didn't occur when he came back online. In either case, it's Alexander that needs to provide the proof, not Harris.
What there is unsubstantiated? What there isn't the most plausible explanation? What does Harris have to show?
I don't think you understand where the burden lies. It's not with Harris and his more plausible explanation, it's with Alexander and his incredible claims.
You're not going to give up on this are you? It's starting to be a bit of flogging a dead horse now. OK here you go
indeed. flog away.