The benefit of hindsight?

I just finished reading this interesting little book, a series of 40 short scenarios of what 'The Afterlife' might be like. Far from making me think about an afterlife, though, this book made me think of this life instead (which I'm sure was the intention all along).

In one scenario, we relive all our experiences in the afterlife, but they are lumped together by category, so you spend six days clipping your nails, then eighteen months waiting in line, then five weeks driving lost, six months watching commercials, and so on.

In another, you only really cease to exist when the last person who remembers you dies.

The one that intrigued me most, though, was where we exist in the afterlife as ourselves at many different ages but whenever 'we' meet, we find we can't relate to our other-aged selves - our 50-year-old self is so different from our 18-year-old self that we find it hard to even strike up a conversation.

It made me wonder whether, if an older version of ourself was able to warn our younger self about the future, would we take heed or still carry on and make the same mistakes?