What a fascinating trip report.
When I first heard of Harris about 15 years ago, back when psychedelic use was still a relatively underground phenomenon and the so-called Psychedelic Renaissance was just beginning, I never dreamed I'd ever see a militant atheist like him transform in to a psychedelic advocate taking "heroic" mushroom doses and having what could be described as powerful mystical experience, even if he's not comfortable using such terms for what he experienced.
I do wonder if his atheism would survive more such powerful experiences. Already, from this one experience, he speaks of understanding how such such an experience could be interpreted in religious terms by those who were already religious. Again, such empathy and understanding is not something I would have expected 15 years ago from such a militant atheist.
Even if he never trips again, I have to commend him for being open-minded enough and curious enough to try psychedelics multiple times, and once at a relatively high dose. Many more close-minded people, who feel completely confident in an extremely one-sided world view, would never chance having their perspective radically altered with psychedelics. Yet he did. Kudos to him for that. If more people were so inquisitive and open-minded the world might be a much better place.
That's not to say that I view psychedelics as a panacea, and I agree with Harris that they're not for everyone. Their use entails real risks, and they can easily be misused by taking them without an experienced guide, without preparation or respect, or in the wrong set and setting. But at the same time, when used constructively, they have a profound potential for encouraging empathy, open-mindedness, improved cross-cultural and cross-denominational communication and understanding. Harris' experiences and transformation are evidence of this.