I think Kubler’s analogy of comparing a single artists life as a unit of study to a single travelers experience on a railroad to be very interesting and extremely applicable to the tangible world. What he means is that while a single artist’s life are important to an artwork or a trend in art, the true meaning of it stems so much further beyond; the artists before and after also need to be considered in order to fully understand.
Another point I found to be really interesting was that similarly to how two scientists of different specialities will likely struggle to understand each other, two painters from different schools have nothing to learn from each other and are incapable of communicating soundly with one another. While I think I understand what Kubler means by this, I personally have a hard time agreeing with it and think it in some ways contradicts his previous point of an artist's biography not being enough information because it does not adequately depict the "whole picture." I feel that as students, we are taught from our earliest years of schooling that we can learn something from everyone. For example, one of my roommates is a biology major and I am a business major, but there have been several instances where things I have learned in my classes have proved to be helpful in her studies and vice versa because it offers a different perspective or new way of thinking.