"Member of hunter-and-gatherer tribe" [sic] is not, uh, a "culture".
Very observing. So, uh, insert a culture of any hunter-and-gatherer tribe you like. Doesn't matter. Just was supposed to demonstrate how culture potentially means a grave difference in a perception of the world, for which you asked. Now you may argue, that this would only be due to different economic/political/social conditions. But it is a false dichotomy to distinguish those from culture. But well, such an extreme example will probably not do much good to our discussion, so I suggest to leave it at that. So here is something more comparable: Family sizes in America versus Germany. I'd like to suggest: A reflection of American culture. But yeah, I have no empirical sound studies which demonstrate the impact of culture with mathematical certainty. If only that can mean a difference in our discussion, the situation is hopeless. I am not ready to believe that yet, though.
You sound like you're tending towards a variant on the Sapir-Whorf hypothesis, that language has a disproportionate effect on the way people think about things, and that people who speak different languages view the world in different ways because of those languages. This is, however, widely regarded to be false nowadays.
Don't know about that. I read an article the other day which claimed that Chinese pupils had an easier times to learn mathematics because the Chinese language was more effective in handling it. But more generally it just to me makes sense that language would have some not negligible sway. It after all is our tool to grasp the world in a communicate-able way. And different languages are different tools. Can't possibly comment on the real proportions. But I personally for instance get a different vibe from speaking English than I get from speaking German. I am pretty sure that I think and reason differently in those languages. How different? Duh, how should I know... But I certainly don't mean to pose this as some kind of over-reaching factor. It is one of many of what shapes and constitutes a culture.
But I never felt like there was some sort of personality characteristic that tended to be more prevalent in Germans than Americans, or vice versa.
It isn't really about personality characteristics as such. When Americans seem more confident, I don't mean to say by that, that Americans as a rule tend to have a more confident personality. I simply mean, that they
seem more confident. Due their culture. I can not possibly tell you what the exact consequences of this are or even that exact nature of it. I don't know if there ever was an attempt to measure cultural differences beyond customs like food or cloths and such. But I know that this exists. I know that it even exists within Germany from personal experience as well as from the exchange of experiences with others. And it simply makes
sense. Because, as already said, we are shaped by our social environment. And this social environment is shaped by culture. And culture constitutes how we perceive the world. It makes absolutely no sense that this was not subject to regional differences and to differences which can correlate with nationality.
Obviously culture has some impact on the way people view the world, but it's only one of a multitude of factors such that people end up being idiosyncratic anyway.
I think here we arrive at the heart of the issue.
At first: Sure, no disagreement there. I don't mean to class personalities individuals have according to their culture
. Obviously other things are (way) more important here. Yet this doesn't exclude the possibility of underling subtle tendencies I don't really want to pin down to specific trades, tendencies which give a group a feeling of belonging, of familiarity, of bond ship. And that is all which is required to debunk your claim that ethnicity was primarily a matter of delusion, of self-identification.
Did you honestly not sense a different kind of "feeling" in Germany as contrasted to America? Nothing concrete. Just what you felt.