Basically what it says in the title
I remember reading years ago in some chapter of what I think is a Kurt Vonnegut book, that the Germans have a word for someone you meet who represents who you could become, but would prefer not to, and how that person is significant as a symbol and drives you to become who you should be or want to be.
Did I dream this? What book was it and what was the word?
Fun fact, the similarity of “father” in different European languages led to Aryan theory. They were originally considered a common culture that all European descended from.