What does "exist" mean?

[markfiend]

While this may sound a trivial question, what does it mean when we say that something exists?

If I say "The computer on which I type these words exists", this would seem to be an obvious truth. But what does the sentence actually mean? I can see the monitor screen, I can feel the keys, I can hear the hum of the cooling fan, etc.

But these are merely perceptions of interactions. I do not see (strictly) the computer itself; photons interact with my nervous system, which my brain interprets as "seeing". Similarly, pressure-waves in air (sound) interact with my nervous system, producing "hearing", and so forth.

All physical properties similarly can only be identified from interactions; a body has mass which we can detect by (and only by) its gravitational interaction with another body, a body has electrical charge which we can only detect by its interaction with electrical or magnetic fields, etc.

What would it mean for a hypothetical object to exist but have no interactions with anything else? We would be unable to detect such an object; as it would not interact with our senses or with any detection apparatus.

I submit, then, a working definition of "to exist" as to interact. My hypothetical non-interacting object cannot exist in any meaningful sense, as it has no detectable effect on anything else.

So, in what meaningful way can a hypothetical deity exist? I assert that only by showing that a deity currently interacts with observed reality can a theist show that a deity currently exists.

[spacer1]

Hi Mark,

It reminds me of Schroedinger's cat. I would qualify your assertion by stating that there has to be interaction for us to know that some object exists, but existence isn't dependent upon our knowledge.

[Calzaer]

Very good point, Mark!

The "existence" of something that doesn't interact would be a meaningless postulate, useful only as a Zen koan.

Let me ask a question, though. Is it just as meaningless to discuss the "existence" of something that doesn't interact, but did interact at one point and/or may interact at a later point? In short, can existence be a transitive quality in a hypothetical sense? Or is it continuous, ie, once something exists, it always exists?

Another question: What about something that only interacts subjectively? For instance, the voices in a schizophrenic's head. The don't interact with anyone but the schizophrenic. Do they exist, not exist, or only exist subjectively to the individual person? In short, can existence be subjective?

[Etan]

You say that existance is to interact, and than qualify that later by saying it is to interact with reality. Here are my hopefully unbiased thoughts:

Let me give you the typical theist response: "God interacts with heaven and with us through Jesus Christ, therefore he exists."

No I don't think that makes any since either, but it does mean we have to change the existance defintion around a bit.

I question your definition of "exist" as it is anyways. I think that it would be more clear if you defined "reality" (since it is in your definition). The definitions of reality that I found:

"The totality of all things possessing actuality, existence, or essence."
"That which exists objectively and in fact."

Well now we're stuck. We can't use "reality" to define "existance" and then use "existance" to define "reality." Cirucular logic isn't allowed. What if we defined "reality" as "all things that we have experienced and therefore know to be true." The only things that have reality and maintain interaction with us exist, right?

Well what about planets that have yet to be discovered? Do they not exist until we find them? What about an island that nobody has set foot on? Nobody has interacted with it, so it does not exist?

My point is that you cannot limit your definition as you do. We can only PROVE that things exist through interaction and experience, but through inference and inductive logic we can derive the existance of other things.

For instance, nobody has experienced a black hole. If they had, they wouldn't exist anymore and so their experience would be inconsequential. Furthermore, we havn't ever "seen" a black hole because you can't see them. However, we know they exist through inductive reasoning: We see stuff go near the location where we assume their is a black hole. That stuff disapears. Therefore we have derived that a black hole exists at said location. We know it exists but we have not seen or interacted with it.

This post turned out way longer than it was supposed to be...

[Jobar]

Usually we strain to define God in this forum; not often enough do we try to define existence.

First, we must subdivide existence into abstract and concrete. These two can influence each other; the madman's voices can tell him to act, and those acts then become concrete. And physical entities inspire theories and ideas, in the sane and the mad.

Does God exist in the abstract sense? I don't think that's a problem; nobody questions that the *idea* of God exists. Nor that said idea has a mighty influence upon our concrete reality.

I think that what theists mean when they claim existence for God is concrete existence. There is, somewhere, some thing which is God. I've asked before how believers see this (and gotten no answer). So, I hope that some of our believing regulars chip in to this thread; it should prove most interesting.

[fishbulb]

Words do not have inherent meanings; we impart meanings to words. If you don't know what you mean when you say something exists, then you shouldn't be saying it. I think that it is probably safe to say that what we (as in the consesnus of English-speaking people) mean when we say that something exists is more or less what you think we mean.

It is also true that one word can have multiple meanings or nuances. In English, the meaning or nuance of a word is usually inferred from the context in which it is used. However, there are often times when the meaning of a word may be unclear. In those cases, the person using the word ought to consider using a less ambiguous word or clarifying the meaning, though it also helps if the people hearing or reading the words don't go out of their way to interpret them as meaning something the speaker or author probably didn't intend it to mean.

If someone makes the statement, "god exists," the plain and most reasonable interpretation is that the speaker is asserting that god is a real entity with real substance, just like Margaret Thatcher, the Sun, or the Chrysler building. If the speaker means something different, for example: that god is a force like gravity or a phenomena like time or the expansion of the Universe, then he should clearly stipulate that this is what he means by "exists." Likewise, if he means that god is an abstract, like an idea or emotion, then he should stipulate this. If there is a reasonable chance that a person's words will be misunderstood or not fully understood, he should take care to elaborate or choose alternative wording.

This would be infinitely more productive and a real time saver over trying to debate some all-encompasing meaning of "existence," which would inevitably end up being so broad and vague as to be useless for actually differentiating very many things from one another. Human language is, by nature, imprecise and we rely not just on grammar and semantics but also on context, consensus, a shared frame of reference, and a mutual desire to communicate in order to convey our meanings.

[Jinto]

For instance, nobody has experienced a black hole. If they had, they wouldn't exist anymore and so their experience would be inconsequential. Furthermore, we havn't ever "seen" a black hole because you can't see them. However, we know they exist through inductive reasoning: We see stuff go near the location where we assume their is a black hole. That stuff disapears. Therefore we have derived that a black hole exists at said location. We know it exists but we have not seen or interacted with it

Ahem. I don't know what you call it, but I'd call exerting a gravitational pull on large quantities of matter "interaction." A truly non-interacting object would be, say, the invisible, immaterial, heatless-fire-breathing dragon in my garage. Which, predictably, doesn't exist.

[Ojuice5001]

What about hypothetical parallel universes? Don't quantum physicists argue about whether they exist, while at the same time they all agree that we can't ever expect to interact with them even if they do?

Actually, though, I agree with this thread to the extent that it's pointless to believe in the existence of non-interacting deities. I think the real problem with an invisible dragon is that it could just as easily be a giant rat, and everything else would still be the same (thus you'd never know, and calling it a dragon is rather arbitrary). Similarly, with a non-interacting god, it doesn't make a bit of difference whether there is one or many, whether it is personal or impersonal, so you can't go very far in talking about such a god.

[Jobar]

What about hypothetical parallel universes? Don't quantum physicists argue about whether they exist, while at the same time they all agree that we can't ever expect to interact with them even if they do?

You've answered yourself, Ojuice. 'Hypothetical' means that it's an idea which may or may not be true (i.e., exists concretely.) Yes, parallel universes, metaverses, and other such abstractions may exist, and it's certain that right now we have no idea how to prove/disprove their existence. The discussions are directed toward finding such a proof or disproof of their concrete reality, by theorizing and looking for possible interactions with our observed universe.

[Z500]

Originally posted by Calzaer
Another question: What about something that only interacts subjectively? For instance, the voices in a schizophrenic's head. The don't interact with anyone but the schizophrenic. Do they exist, not exist, or only exist subjectively to the individual person? In short, can existence be subjective?

they do exist. they are just electrical impulses, like our regular 5 senses, but not a result of external stimuli. who's to say any external stimuli exist at all?

[xorbie]

I think by all definitions of external, external stimuli must exist to some extent. Unless, of course, you wish to posit the theory that you are nothing but some amorphous consious and that all of the physical world is a falsehood. In which case, have fun.:rolleyes: