> Too hard to believe ... It continuously amazes me the extent to which we (collectively) under-estimate human ingenuity - especially of people in the past. It

> Too hard to believe ... It continuously amazes me the extent to which we (collectively) under-estimate human ingenuity - especially of people in the past. It's like we have a built in belief that current-era humans are as smart as we get. If anything in the past - especially the very distant past - seems unbelievable to modern eyes, some will go as far as conjuring advanced, space-faring beings that "must have" either built those things, or aided humans to do so (conveniently ignoring the fact that the advanced aliens must have also either developed or acquired their knowledge somehow. "It's aliens all the way down"). EDIT: I'm not having a go at the commenter! It's just that the opening comment seems to hint at a universal trait that people have to disbelieve clever stuff from the past.