So much understanding of the world we live in can't simply be put into words, but understanding can only be acquired by experience. Even something as mundane as the passing of time is experienced differently as an adult as opposed to as a child. For a little kid 5 minutes feels like an eternity, whereas many elderly wonder how so much time passed them by in an instant. Time actually passes by faster as you get older, so a lifetime is both an instant and an eternity, depending on your perspective. This is a fundamental obstacle to the transmission of wisdom from old to young, that a lot of what old people tell young people, no matter how true it is, simply cannot be grasped by them until they get older. Even within the course of a lifetime you pass through several higher and lower stages of awareness, and there are some things that can only be grasped at higher stages of awareness, which can be attained only by hard experience.