Interesting. It seems your early Jewish teachers were firmly stuck in the mindset that was one of the things Christianity originally arose to combat. (Not that Christians should feel too haughty about that since the vast majority of Christian sects fell right back into the same trap early on. I find it amusing that “The Lord’s Prayer” is repeated by-rote in most sects when in-context it was given as an example of how you shouldn’t waste your time with by-rote prayers...)
This is as opposed to the Jewish community in and around Salt Lake City in the early 1900s that my grandfather always told stories about. (Although I must admit the possibility that the stories were modified to better carry whatever principle he was trying to teach at the expense of strict conformance to history.) To them the best prayers were actions. Prayers-of-words were useful only insofar as they led to choosing the best prayers-of-action. If your neighbour’s barn burns down you don’t stand around muttering prayers that they’ll be able to recover from the disaster any longer than it takes you to figure out who can contribute what—and then you go out, build them a new barn and stock it for them. Prayers-of-words-you-don’t-understand are worse than useless. They are a distraction that leads you in entirely the wrong direction. Prayers-of-words-that-don’t-cause-action are empty and useless—intermediate steps detached from their terminal goals. But we lazy humans are creatures of ritual and habit and pattern-matching. If we experience often enough a chain of events that starts with words and ends with desirable outcomes we eventually become tempted to think that all we need to do is start the chain and not give any thought to the middle steps. If every day at 4PM we take our keys and get in the car and drive to the store and buy some chocolate we may well find ourselves wandering the aisles aimlessly despite having heard about the chocolate-destroying-earthquake prior to having left the house. Because we weren’t actually thinking about it.
“Things we do without thinking—There’s the real danger.”
Another potential reason for the disparity in social reaction to overconfidence vs underconfidence may be that, for primitive people, overconfidence would likely get one killed immediately when taking on too large a challenge while underconfidence would merely result in being hungry but usually living to find another opportunity later.
In the modern world very few of our challenges are of a nature where failure results in immediate death, but our brains are still wired as though we’re debating the wisdom of leaping onto a mammoth’s back. Being pack animals we are naturally inclined to curb the exuberance of others to avoid incurring fatality rates that would jeopardize the survival of the tribe, but most of us have a mis-calibrated scale due to never having had to take on significant, life-or-death decisions.