"Memory is a strange thing, it doesn't work like I thought it did. We are so used to thinking of it as a camera or a tape recorder, but it's not like that at all. It's more like a painter, who adds and subtracts elements according to his own rules."
Courtesy costs nothing. Lower the toilet seat after use. Let the people in the elevator exit before you enter. Return shopping carts to their designated areas. When you borrow something, return it better shape (filled up, cleaned) than when you got it.