So there you are sitting at home by yourself minding your own business when you hear a knock at the door, you go to answer it only to find…you standing there.
Sure with a little closer inspection ‘you’re’ a little older looking, wearing unfamiliar clothes etc but its definitely you, at least physically.
His (or her if you’re of the feminine ilk, swap future pronouns as necessary) first words are, “Don’t panic, I’m you from the future, and I’m here to help. Trust me.” He quickly explains that he’s come back in time from an unspecified future date to rectify something that is going to go horribly wrong in your near future, all you have to do is trust him and he’ll sort it out but its important that other people don’t realise there are now two of you.
So, do you? How far would you trust ‘yourself’? What would you ask future you?
I would ask ‘myself’ about a certain failsafe that I came up with when I was a little boy and thought about these kind of things rather regularly. If he answered correctly then he is either me, or someone has gone to a LOT of trouble to dig out this little tidbit of information from my mind without my knowledge.
Then, I would ask him for particulars and essentially trust him as I would myself.
If, on the other hand, he didn’t get the right failsafe then I would pretend to trust him until I could disable him and call the authorities.
But your older self would remember all that, as well as everything you did forever after your older self showed up, so your older self wouldn’t have to go back in the first place.
Unless, quantumly speaking, he’s from another universe/timeline or wanted to kill his grandfather in the interests of science. Or sumpin.
It depends upon which model of time travel you buy into. If there’s only one time stream, then it seems weird that you have to go into the past to help yourself, but presumably Future You knows this and does exavctly what he remembers, maki ng it come out “right” (or at least the way he remembers). But it does make you wonder what the result would be if Future You decided to act differently than you remember, or not to go back at all.
If you believe in a “many worlds” type of timestream, then everything that happens after the intervention is up for grabs, and Future You might not be any help at all.
At this point I’d like to quote my first Sig Line:
Similar to Gagundathar, but I wouldn’t ask him anything. If it’s really me, then he already knows what he has to tell me to convince me.
Kenm, I think the idea is that if the person at the door doesn’t know the failsafe, it’s because they’re not really who they claim to be, and thus wouldn’t know one’s plans.
You have to be careful in a situation like this because Bill and Ted got thrown off Vasquez Rocks and died because they believed that the Evil Bill and Ted robots were actually them from the future.
On the other hand, Ron Silver got smooshed up into himself, creating a nasty mess when he touched his future self in Timecop.
So I would have to be very careful to make sure this plays out right.
I’d ask him about a certain sexual preference that I have never mentioned to anyone. If he knew all about it, I would believe him and do what he says. After all, I am his past.
If he really was me from the future the conversation would go like this:
Present Me: You know what question I’m thinking of. So what is the answer?
Future Me: Cranberries and soap, all day long.*
PM: And the follow up…?
FM: Only when I drop the big hammer on my foot.*
PM: You know what we’re going to do once this over. And you know I have the advantage because I’m younger.
FM: Ha! There are some things you haven’t learned yet. But the duel can wait until we’re finished with this other thing.
If the guy isn’t really me then he’ll know neither the questions nor the answers. In that case we’ll proceed directly to the axe duel, and this one will be to the death. After all, anyone impersonating my future self is up to no good, and they’ll certainly do something to dishonor my future good name.
*Not the actual responses. But they make just as much sense to anyone else who isn’t me.
If it was me from the future and I could remember anything that wasn’t earth shattering I would immediately know it was a phony. My kids give me a hard time because I have to look up their birthdays, my memory (or lack thereof) is legendary.
I think I could come up with a couple of items to verify I am me however and I would trust myself once I did.
I think the test is designed to ensure it really is a future version of you rather than a well-disguised imposter playing on your instinctive self-trust.
He’s not exactly the same person as you if only because of the alleged passage of time.