There is no flaw in his argument. He's given to a very aggressive skepticism.
The question I would pose is what grounds would you havefor adhering to the conjecture posed. If you accept his argument, what about your behavior should change? Can we derive any knowledge from his conjecture? If "no" and "nothing", then it's a valid question why we should believe it. If he persists, point to David Lewis and linguistic assent (outlined, wuite entertainingly, in "Elusive Knowledge"): that he can consider your view and his completely equivalent insofar as either of you have knkwkedge of any kind,.
Also, excuse my drunkenness.
Also, excuse my drunkenness.
I thought you were just making typos. This is surprisingly clear for the writings of someone inebriated.
So I have a friend who I sit next to in class, and we talk about philosophy. Well today, he brought up that when people leave your presense, and you can't observe them any longer, you no longer have proof they exist.
Well I pointed out that it would violate the conservation of mass law, right?
So then, with a bit more prodding, I figured out that by "no longer exist", he means they exist in their world, but they no longer exist in mine. So basically you can't prove that anyone exists unless they're directly in front of you.
I'm really not certain how to go about answering this question. I mean, he challenged me to prove that my mother existed, without seeing her. Obviously I couldn't.
Is he right? Or is there some flaw in his argument, some fallacy that I'm missing?
I went through a few of the Sequences, and the closest article I could find was about not believing in the invisible. But in this case, he doesn't literally (I think) believe they just vanish, he believes they enter alternate universes that are selected when I come in contact them again.
My mind is boggled. I also apologize if this is dumb question, and it's common knowledge or has already been answered, and to my credit, I did make an attempt to figure out the answer before bothering you all. Thanks.