It's exactly like time travel, for an audience of one.
There is a thought experiment that we do every now and then, when we are 16 and we imagine ourselves talking to our older selves that are yet to be- telling them what we expect from them. Sometimes we do this experiment because all of the adults in our lives are looking for us to perform this task. They will give us a round number - "Where do you see yourself in the year 2000?" They will ask us this in 1984.
They will raise the stakes - where do you see yourself in they year 2020 - because it sounds cool and impossibly futuristic, even now.
Sometimes we will ask ourselves the question in the middle of the night - our nascent selves keeping away from the numbers and going to the dreams or the ages . Who will I be when I am 30? What will I have to give up if I go for what I want now? What will I keep if I have to give up what I want?
We are 16, we are not fools. There is no real innocence at that point, we've learned to compromise, we've encountered limits, sometimes they can be overcome and sometimes they can't. The adults remember this time as full of possibility and see us all as impossibly hopeful, but if we're even a little awake, we know. We know our parents were 16 once and very, very few of them are doing what their 16 year old selves wanted for them.
The implacable hope is armour - the firm absolutism of our belief systems is not naiveté, it's the fear we'll lose sight of it later, when We are Them. It's not always because we haven't lived life, sometimes it's because we have. Silly grown-ups, how strange you are when you edit your younger selves. How could you have forgotten that metal tinged taste of the entire future before you? Didn't it cut your tongue a bit? Do you only remember the relationships and erase the analytics? Is it easier that way? Is it numbing? Is it better? Maybe it is.
On the other side of the question though are the adults who are in their older selves - looking at the raw open youth, seeing them with the eyes of those who made the choices, and found some things the 16 year olds infront of them couldn't have imagined as being worth the price then. Or things had changed so much for them that they can't imagine the 16 year olds they were - that person is lost to them - a myth of self.
So when the older person asks the younger to imagine talking to a future self - are they looking for redemption? Information? I know it depends: On the 16 year old; on the 36 year old; on the 66 year old in question.
I know older people (older than 16 at least) who have running conversations with their younger selves. They are explaining. They are apologizing. They are angry, or sad, or triumphant.
And in every case their 16 year old selves are unchanging and static, yet somehow accusatory, or disappointed, or pleased. Even though they never answer back.
I wonder what that is like.
I think it's simpler somehow. It makes the immortal commandment of Polonius easier if thine-own-self doesn't answer back.
Of course if you knew 16 year old me- as I do - you would know that the idea of not answering back is anathema.
I am quieter now.
I/She just waits until I can't avoid the conversation anymore.
Where do we see ourselves in 2020? It sounds so impossibly futuristic.