What I never end up understanding about such topics is what is truly meant by "understanding" [that we have finite lives]. Don't we all know that anyways? Are w

What I never end up understanding about such topics is what is truly meant by "understanding" [that we have finite lives]. Don't we all know that anyways? Are we being asked to calm down and accept that? If so, isn't such futile for those that couldn't initially (as I don't see how reading a book would change their psyche) and placebo for those that could (as they've just never considered life in that way)?