Powder and stone, or, why medieval rulers loved castles

IME, it's not popular to say it on HN, but it's essential to know your author - information is never divorced from a person (sometimes it's a programmer). You're not smart enough to evaluate knowledge unless you have expertise yourself, and even then it's essential to know who wrote it - note that is the lead piece of information in scholarly cites. Here I see no description beyond,

> I try to learn all the time. I make stuff sometimes. And dream about space the rest of the time. Proud Neptune-stan. Ask me about Neptune.

And here is their process:

> the synthesis of parts from several books + papers and discussions with friends

Also know the institution, in this case the 1517 Fund. From their About page,

> In 2010, our team cofounded the Thiel Fellowship with Peter Thiel to prove out a simple belief: great founders don’t need university degrees. That was a $100k grant program – and it gave birth to projects like Ethereum, companies like Figma, OYO Rooms, and Luminar, and funds like the Longevity Fund. We started 1517 to scale that further and expand the support and community that the Thiel Fellowship started.

Just-a-guy-on-the-Internet, and in an org with an agenda, is the source of all sorts of nonsense.