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True Existence

  1. Jun 7, 2005 #1
    Can any of you prove the existence of someone or something around you? Or better yet, your own existence? Because the only thing you can really know for certain is your own mind's existence, and even that, one can argue, doesnt exist.
  2. jcsd
  3. Jun 7, 2005 #2


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    short answer: no
  4. Jun 8, 2005 #3
    Well, u know that you exist, because, a thought process is existence, and if we can think, with the definition of existence, you know that atleast you exist. But can we prove other things exist, thats another story. Even if they were apart of our mind that we made up, would they not exist there? Even if this never happened, or isnt in the real dimension, it still existed. I have no doubt i exist, and the world that my mind sees does.
  5. Jun 8, 2005 #4
    But how do you define what thought is? What I'm trying to say is how do you know your thoughts arnt a compilation of tiny particles all working together to create some bigger thought. Its hard to explain but it makes sence in my mind. At least what I think is my mind.
  6. Jun 8, 2005 #5
    That sounds cool; it makes sense that that's what thought is. Or maybe it's something else but cool definition.

    I can only really prove I exist if you're convinced so it's technically up to you.
  7. Jun 8, 2005 #6
    Good point. I have complete control over what exists and what doesnt exist. You officially don't exist. Just kidding. So I can basically think/convince anything out of existence. The only hard part would be convincing myself that things like gravity or other forces don't exist, or even better thinking myself out existence.

    So how would one go about convincing someone that they exist, rather than proving that they exist?
  8. Jun 8, 2005 #7
    They're the same thing.
  9. Jun 9, 2005 #8
    ya I realized that shortly after I posted it.
  10. Jun 9, 2005 #9
    Without getting into semantics I will say...

    Matter exists.

    Therefore everything you see exists. Your keyboard. Your watch. Your hand. YOU!

    You "exist" because you typed this post on the keyboard in front with your fingers using your mind.
  11. Jun 9, 2005 #10


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    Does it? Are you absolutely sure? How would you convince somebody who insisted it didn't, or who said you didn't have sufficient reason to claim it did?
  12. Jun 9, 2005 #11
    Not to be flip but how would you convince someone that matter doesn't actually exist?

    You can reach out and touch your keyboard to type this. If you die tomorrow someone else can reach out and touch the same keyboard independent of you (to tie into the argument of reality exists only in your head). In 1000 years someone will be able to reach out and touch yourr keyboard (or whatever it was recucled into). 100,000 years the same thing. 1,000,000 years from now the matter that made your keyboard will still exist, in what form who knows but it will exist.

    Another way to do it would be to say that when the big bang happend it produced "stuff" that fills this universe. The stuff exists independent of us (man). I'm calling that stuff "matter" (it might not be the best term).

    Do either of those statements prove matter exists? I guess that depends on you tastes in philosophy.
  13. Jun 9, 2005 #12
    You cant say matter exists simply because it will be around in 1000 years because you wont be here to verify that. Also, how do you know your actually reaching out and touching anything. The keyboard could be an image created in your head, and the feeling of touching it could also be created in your head.
  14. Jun 9, 2005 #13
    ur13: you have commited a logical fallacy. You are assuming as existent what you're trying to prove as existent. Besides, you forgot one premise: that everything is matter. So you proof proves nothing. Basically is the same as saying "apples exist because they exist".
  15. Jun 9, 2005 #14
    Well the earth contains fossils that can be carbon-dated to well past 1000 years. We have texts that were written over 1000 years ago. Etc etc...I just picked a random number.

    I know the keyboard exists because I am touching it. It isn't a construct of my mind. It is completely indepedent of me. Thus you or the next person could come here and type on it if I was gone. Do I know it will be here in 1000 years. No. However I know the matter it is made up will be here. Maybe my example wasn't the best but my point is that the universe exists independent of consciousness. How many millions of years has it existed before man or "life" for that matter?

    How can I be so sure? I can observe reality and that things exist. Consciousness is man's ability to perceive what exists.

    How about this. Imagine you are thirsty. Now if we went by your thinking you would wish a glass of water into existence in front of you. When was the last time you did that? Existence exists so you need to get up out of your chair, get a glass out of the cupboard and put it under the faucet and turn it on and fill it. Try as hard as you like to sit in your chair and wish it into existence it will never ever happen.

    "Apples do exist because they exist."

    Existence is an absolute. Like I said existence is independent of our wishes and hopes. The apple will exist whether you want it to or not. Ok so you eat the apple. It no longer exists, right? True, but the matter that made the apple still does. Said matter will become part of you or you will get rid of it as waste. The apple might not exist anymore but it's matter does as does what an apple is (a fruit of a tree).

    Again nothing you do with your mind can change that. You could go around the world and destroy all the apples, all the seeds and all the DNA (good luck) and the "apple" will no longer exist but all that matter will in one way or another.

    Just as existence in independent of our wishes it is independent of the apple's wishes (do apple wish?)....
    Last edited: Jun 9, 2005
  16. Jun 9, 2005 #15
    Sense aren't reliable when it comes to proving. "To prove" basically means "to demonstrate" without doubt, based on TRUE grounds. Sense-data is far from being "evident" or "true". See Descartes's First Meditation for a nice view on this matter.

    Why you keep assuming that the world we see is "a fact-based reality"? Most philosophy is based on being somewhat skeptical; critical. Why you think that the real world you see, smell and touch isn't the result of some hidden mental-activity (subconscious can work as an example)?

    If you want to prove something about x, you can't assume it as true. That's not a proof. Just a reiteration. I'm going to formalize your argument:

    - What we want to proof: That apples exist
    - Premises (truths)
    1. Apples exist
    apples exist.

    Is that really a proof? I don't think so. Think about it for one minute and realize the absurd "proof" you just made.
  17. Jun 9, 2005 #16
    Ok prove to me that reality IS a result of some mental-activity.

    The universe was here long before we were, long before life for that matter. How do we know? We can date organic matter.

    Secondly, I'll repeat this. You are thirsty. You can wish or try to mentally create a glass of water all you want but it will never appear. You need to actually get up and get it yourself.

    I am familier with Descrate's "Universal Doubt" idea. I suppose I see things differently.
  18. Jun 9, 2005 #17
    So you're holding on to your so-called proof because you don't have any counter-proof that proves yours as wrong? That isn't very "philosophical" from you.

    A: God exists
    B Why?
    A Then prove that he doesn't exists
    A: God doesn't exists
    B: How come?
    A: Then prove he exists

    That doesn't proves anything about God's existence, does it?
    Last edited: Jun 9, 2005
  19. Jun 9, 2005 #18
    So what? If (let's suppose) the "reality" you see, smell and touch is the product of some "mental" faculty unknow to you, you can't tell what are the limits of that faculty, or even tell how does it operates. Again, your argument fails.

    I was also talking about the "evil genie" idea. Are you familiar with that one too? I guess not.

    The point is that you see things like common, average people does. That x exists because we can see, smell and touch x. There is no difference between your position and the "popular" position. Descartes (and John Locke too), on the other hand, did had a different position that you should learn about.
  20. Jun 9, 2005 #19
    You cant prove that things have always excisted just because of carbon dating or texts. The texts and all the fossils with a certain carbon make up could have been created as soon as you were born to accomodate your entire life. Going along with what Marostos was saying, the reason we cant make glasses of water appear in front of us is because we cant and never will understand our sub-constious imagination, if there really is one, creating our reality. Just because you see something, or feel something, does not make it real.
  21. Jun 9, 2005 #20
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