That’s a very cool app, but I think it is missing many, many references to books in HN comments? It only has like 15 total sci-fi books. I don’t see any of my comments mentioning some sci-fi books.
It's a bit old. I bookmarked it a while ago, I don't think it has an update mechanism. A daily frontpage pull + AI parsing should be enough to keep it up to date.
That saying, or ones like it, are also attributed to Carl Sagan, G. K. Chesterton, James Oberg, Arthur Hays Sulzberger, Virginia Gildersleeve, Bertrand Russell, Max Radin, ...
This article mentions Walter M. Kotschnig as the author of the earliest known instance of the saying, but notes that even Kotschnig seemed to be quoting something that was already known at the time:
An appropriately simplistic quote from someone who habitually and sometimes famously demonstrates being stubbornly narrow minded. But then, how else would he not know that brains don’t fall out of—nor are placed in—minds.
