I am by no means a native, but since it's helpful for my Japanese, here's an attempt: All individuals are under the false impression that their particular version of the mental "cloud" that one sees as they mature is the only correct form that such a "cloud" can take. As a result, when this mental cloud changes ever so slightly with each generation, it causes people of different generations to be at cross purposes (because they are unaware of this change). At first I presumed 'cloud' was some kind of mental haze...but now I think it's probably more like "belief system" or "values"