krazykidd said:
I have decided you are all fragments of my imagination. Prove to me that you aren't. Prove to me you exist.
These are two different questions.
I clearly exist. If you understand "I" in this context as being the indexical device that points to the origin of this particular statement, then in order for the statement to be meaningful, "I" must refer. You perfectly well understand the statement, because even if "I" is just the same as "you" in this post, it still has a direct referent. So "I" successfully refers, and hence "there exists x such that 'I' in the context of a post made under the user title "Indeterminacy" refers to x" is made true.
What your first question is asking, however, is about the identity conditions for being "me". And in fact, it is perfectly legitimate to think that the identity conditions for being "me" are identical to those of being anyone else, or could be identical with some fictional entity you've created to make sense of the data you encounter.
However, here is an argument to suggest that if this is what you think, you're necessarily equivocating:
Let us suppose that you are just a brain in a vat. You are fed sensory stimuli directly by an electrical connection to a computer simulation. Now, suppose this brain in a vat responds to an item of sensory stimulus by thinking the phrase "That is a tree".
Does "The Tree" really exist? Is "The Tree" merely the construct of a computer program? Well, let's ask something. What do you refer to when you say "that is a tree"? You clearly don't refer to actual trees, since you've never seen an actual tree. You also don't consciously refer to "a particular series of computer generated images fed directly into my brain", because actually, the computer doesn't feed to you the fact that you are just a brain in a vat.
"Tree", on the thoughts of the brain in a vat, actually refers to something going on in the simulation. In fact, so does every thought the brain might have: Including the thought "everything I see is just a computer simulation". Being a computer simulation, to the Brain in a vat, just means being a computer simulation
within the simulation, and does not extend to the kind of simulation that actually composes everything the brain experiences.
Now, to generalise. You've proposed that we're all a figment of imagination. But Whose Imagination Are We A Figment Of? Yours? Well, you are a feature of the sensory world you experience too; or rather, your having experiences is something that constitutes the things that you're proposing to be imaginary.
It would be either an equivocation or false to say that we are all only in your imagination, because you're already presupposing that there is a dividing line between "you" and "us", and between "imaginary" and "real"; a division that's only in the imagination you're supposing we all exist in. In the imagination, we clearly are different from you. Outside it, you have no means to refer to yourself independently of referring to us.
Therefore, not only do we exist, but given the mode of our existence, we're not imaginary either.
QED, biatch.