I think my instinct is to do something like cryptography... have a secret that Alice and Bob combined would put together that I could only confirm without telling them beforehand. So I know there was a transfer of information from Alice to Bob without my intervention. But the problem is that even my confirmation source would be within my consciousness somehow even if I didn't tell them personally. Tough problem.

I probably shouldn't say this, but after all my years of troubled interpersonal relationships, I'm in a position right now where it doesn't really matter if anyone else exists, and I LIKE it that way.

lol.. I hear ya man.

I actually just googled this problem while thinking about Descartes's stuff and it's apparently still unsolved... I should read up on what approaches people have taken to grappling with it though

If I did, it would prove I exist. Otherwise, you'd have designed it, and I'd just be a figment of your imagination.

I would look and listen at the door to see if anyone was home, then knock. Before they answered I would be sure to have an excuse at hand, like borrowing eggs, instead of telling them I was just checking to see if they exist. Otherwise I'm pretty sure I know what their reaction would be.

Or I could pinch myself really hard on the arm. As a certain science officer once said, "Life is not a dream."

Have a stranger punch you in the nose. If you bleed they were real. You didn't punch yourself, did you?

If I did, it would prove I exist. Otherwise, you'd have designed it, and I'd just be a figment of your imagination.

*mind blown*

Whether others exist, on a logical level, is a question of how you organize your thinking about things. In that sense,it's like free will. But, if you understand how to transcend the logical level, the question goes away.

I think one way to approach this idea is through a sort of neural idea of how your brain works. Say someone tells you they read a book, right? A book I haven't read, like Conrad's Heart of Darkness.

I'm like, okay, that's something that happens in the book! I've never heard of that. Then I go check out the book, and what do you know, intertwingled right in the plot somewhere is the detail the Other Person told you.

Now how likely is it that your brain had already constructed the whole Heart of Darkness plot without you knowing, told you upfront via an imaginary person without you still knowing, and then you read the book and find out the spoken-of things for the first time? Very unlikely!

that's it I've solved it!! Should've given me a call, René!

(Okay this doesn't quite work because I've definitely dreamed of reading things that my brain constructed without my knowledge. Damn.)

Obscure Reference, true enough. In fact the reason I was thinking about this again is because I saw some news about scientists doing an experiment to figure out if our universe is just a simulation. And my response is--if it is a simulation--alright? Then what? You still have to live, and die, and love... you may "be fake" but you still have to "be". It gets into that existential sort of space

"I refute it thusly!"

Even if the universe is a simulation, doesn't everything in it still exist? What does 'exist' mean anyway? If you think you exist, then surely you exist?

The question is if it's objectively true. If you can dream of a hand and it looks real, and you're awake and your hand looks real, is your hand real or not?

But your last sentence is what what Cogito Ergo Sum argument is--that even if my hand doesn't exist, as long as my *thoughts* exist, there must be some "me" that's inarguably "real".

If I remember correctly though Descartes was trying to get somewhere else from this concept--into dualism between the mind and body--so although it seems like a dead-end argument you can build a way of thinking on top of it