Theoretical explanation for observed reactions: Lemma 1: alien topic is like religion, not a great amount of data, but very high stakes. Lemma 2: There's a lot of intellectual "soccer mums" on HN eager to find an outlet for their unrealized (?) intellectual prowess. Corollary: Alien topic seems like fair game, because low risk associated to bring wrong, and hard to disprove with facts or experts. Theory: this topic manifold provides attractive attachment site for brains looking to engage in intellectual proving games and leads to lots of low signal comments intended to make others wrong to achieve a sense of being right. It will take HN some time to adopt the correct posture to discuss leading edge questions in areas with lots of ambiguity. QED.

But this theory shouldn't be controversial at all: A random sample taken from any distribution is more than likely to be representative of that distribution. It's a basic idea but I like how he's illustrated it here with lots of examples and connected it to the alien notion. Meaning it leads to a good insight. Namely why most described encounters of aliens detail beings that are a lot like ourselves. The so-called five star pattern: a head, two arms, two legs. And hands with fingers.

In fact the ideas advanced in this essay are so fundamental they're like informational entropy or enthalpy/thermodynamics in that they are basic but insightful and sometimes counterintuitive principles that advanced reasoners can use to figure about the world. I wish more people knew of them.

I'm so blown away by this essay. in a limit sense I think this type of reasoning represents the best that you can possibly do starting from a position of ignorance. And as essay says that position is the safest one to start at. Sure you can apply a bunch of priors and constraints to limit the variations of different populations to what you think is right but really in this topic those things are just distortions. so the conclusions arrived at in this paper I think are in the limit sense the best that you can possibly do from the intellectually honest position of almost totally ignorance about this.

it's telling that so many people want to instinctively reject this and instead blindly impose their own priors while being blissfully unaware that's exactly what they're doing, resisting the general purpose conclusions of this essay and trying to pass off their own beliefs as truth.