"We found ourselves discussing the three kinds of fateful choices that exist in the two books: the ones characters make knowing that they can never be undone; the ones they make thinking they can but learn they can't; and the ones they make thinking they can't and only later come to understand, when it's too late, when "nothing can be undone," that they could have. Mom had always taught all of us to examine decisions by reversibility--that is, to hedge our bets. When you couldn't decide between two things, she suggested you choose the one that allowed you to change course if necessary. Not the road less traveled but the road with the exit ramp."