This is oddly different from what he said in person. Also he wrote the first edition of mctb also about twenty years ago now, so I wouldn't be surprised if his opinion is different from his thirty year old self.

I don't think you need to take any of the Buddhist claims seriously, just do your own investigation. I think it's much closer to something like 'people take instrumental goals as terminal, then twist themselves into knots over this error'.

Ingram has actively hunted for any jhana hunters for twenty years and hasn't found any. The reason why becomes obvious once one gains a bit of insight into why/how jhana works. Though it's trickier to describe.

I think letting go of desire is a terrible description of the insight. I still feel like a normal person, I just suffer a lot less. There's a tendency to overestimate the magnitude of changes in their close aftermath. It takes a few years before the mountains truly are mountains again.

More objective psychometrics like neuroticism and the reports of friends, family, partners.

They're coextensive/parasitic on virtues, virtues being hard won compressions of lots of contextual information about how to prioritize and behave for min-maxing costs and benefits in a side-effect free way. Since virtues are illegible to younger people who haven't built up enough data yet, values are an easy attribute substitution.

Imaginal worlds, escapism. Video games, tabletop gaming, fantasy movies and books, comics and anime, collecting things, model building or mechanically intricate things.

Puzzle games and real math are pretty non central examples of nerdy interests in my ontology. I think of nerdy interests as fake compression, they provide a simpler world with a working memory number of variables to optimize instead of the mess of the real world. Results can be knowably optimal etc.

In both examples: 2 degrees of freedom, two pieces of information. The information is sufficient to restrict one of the degrees of freedom (to within some bound in the second clustering example rather than precise).