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Tell me if this makes sense

  1. Jul 8, 2006 #1
    Hello,

    I found an interesting post on another forum, but I can't fully make out what was written. Basically, the poster tried to use mathematics to show that there is life after death, or rather the life of conscious soul that lives even after a person dies. He also used some formulas, or some expressions, which I don't understand. I found it pretty interesting, and I hope that it has some validity to it. I'm not sure if I can post links to other forums, so I'm copy/pasting the entire post:


    I performed a very basic formal logical analysis of a couple of statements, and came to the conclusion that being alive is not necessary for being conscious (i.e. self-aware) and intelligent. In other words, there's a chance that our souls do not disappear after we die, and that the technology like brain uploading is quite plausible. Additionally, in order to be self-aware it takes more than merely being alive, which makes me think that we humans are not closed systems, and might have a link to some external unknown system or a source, and that phenomena like astral projection for example might be real.

    The analysis I performed is explained below.

    1) Let's assume that it's necessary to be biologically alive (A) in order to be conscious (C). In that case, C=>A. We may say that if a person is conscious, then he/she is also biologically alive, which is true (C=t, A=t, (C=>A)=t). However, a contradiction to this would be the statement that if a person is not conscious, then he/she is not alive either, which is clearly false, just think of brain dead people (C=f, A=f, (C=>A)=f). But this needs to be true in order for the original statement to be true.

    2) The same reasoning applies to the statement that a person must be biologically alive (A) in order to be intelligent (I), in addition to be self-aware. It is true that an intelligent person is also biologically alive (A=t, I=t, (I=>A)=t), but it is false that an unintelligent person is dead (e.g. not biologically alive), and the prime example of this would be our "special people" brethren: (A=f, I=f, (I=>A)=f). Hereby lays a contradiction, which also negates our original statement.

    3) And finally, let's prove that a human being is not just a sack of meat and bones, a bunch of chemical processes inside of a brain, etc. For this, let's say that being biologically alive (A) is sufficient for being conscious (C), or in other words that a human being is a closed system. Is it true that when something is biologically alive it doesn't have to be self-aware? Think once again of a brain dead person, or an animal tissue cell, or a plant? Yep, it's true. Thus, after showing that (A=t, C=f, (A=>C)=t), we conclude that simply being alive IS NOT enough to possess self-awareness, or consciousness, or soul, and that something else (who knows what) is required.


    A more detailed example:

    Initial statement: being biologically alive (A) is necessary for being conscious (C), i.e. C=>A

    Let's construct the truth table:

    A C (C=>A)
    T T T
    T F T
    F T F
    F F T

    Now let's check if the truth table and the initial statement hold:

    T,T,T – if a person is conscious, then he/she is also biologically alive (pretty obvious, eh?)
    T,F,T – if a person is NOT conscious, he/she is still biologically alive (as in a case with brain dead, unconscious, etc.)
    F,T,F – if a person is conscious, then he/she is NOT biologically alive (this is actually UNKNOWN, so lets assume it to be true for the sake of the argument)
    F,F,T – if a person is UNconscious, then he/she is NOT biologically alive. This is false (F), as was demonstrated above, therefore the initial statement is not true either. Being biologically alive is in fact NOT necessary for being conscious.


    The other two statements were proven in a similar wa


    Btw, I'm new and I like your forum a lot :) I think I'll be checking it out from now on.
     
  2. jcsd
  3. Jul 8, 2006 #2

    arildno

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    ") Let's assume that it's necessary to be biologically alive (A) in order to be conscious (C). In that case, C=>A. We may say that if a person is conscious, then he/she is also biologically alive, which is true (C=t, A=t, (C=>A)=t). However, a contradiction to this would be the statement that if a person is not conscious, then he/she is not alive either, which is clearly false, just think of brain dead people (C=f, A=f, (C=>A)=f). But this needs to be true in order for the original statement to be true."

    This is a trivial case of misapplied logic. If C implies A, then it by no means follows that not-C implies not-A, as the poster seems to say.

    What DOES follow, is the implication not-A->not->C, which is something entirely different.
     
  4. Jul 9, 2006 #3
    arildno

    Thank you for your reply, but unfortunately (to me, anyway) it sounds even more confusing than what I quoted in my initial post :uhh:

    And by the way, I read through this forum and the opinion that soul or some equivalent thereof does exist seems to be prevailing. o:)
     
  5. Jul 9, 2006 #4
    You want to know if this makes sense, using mathematics to show there is life after death? Are you serious? :eek: :eek: :eek:

    No it does not make sense at all.

    EDITED: well this comment gave me a warning from some of the moderators for being annoying. In my view if there is one thing annoying it is using mathemathics, which is not even an empirical science to begin with to prove things about the supernatural.
     
    Last edited: Jul 9, 2006
  6. Jul 9, 2006 #5
    Hmm, when asked a question - "Is there life after death?" - how do you respond? Yes, No, I hope there is, We don't know enough to tell for sure but it's logical/illogical to believe that there is? And what facts do you base your answer on?
     
  7. Jul 9, 2006 #6

    arildno

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    Do you at all know what an "implication" is?
     
  8. Jul 9, 2006 #7
    Arildno is quite right.
    The poster seems to be saying that since C entails A (being conscious entails being alive), then it logically follow from this that ~C entails ~A (not being conscious entails not being alive) – but this would be an invalid inference.

    If the statement “C entails A” is true, then logically we cannot say (we do not have enough information to say) whether the statement “~C entails ~A” is either true or false.

    Best Regards
     
    Last edited: Jul 9, 2006
  9. Jul 9, 2006 #8
    arildno

    Please bear with me.

    not C implies not A is the same as to say that "if a person is UNconscious, then he/she is NOT biologically alive. This is false (F)". Or I mean, this is what it isn't. In other words, you said that not A doesn't imply not C, or that it's false, and that's what the poster said too, didn't he?
     
    Last edited: Jul 9, 2006
  10. Jul 9, 2006 #9

    arildno

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    Again:
    It is assumed ordinarily that IF something is conscious, THEN it is also alive.

    Now, the poster thinks that from this, it follows that IF something is not conscious, then it is not alive.

    The statement: "IF something is not conscious, then it is not alive" is evidently UNTRUE; for example bacteria are (presumably) unconscious, but they are certainly alive!
    Thus, if it were true that the first statement (IF something is conscious, THEN it is also alive.) logically implied this patently false second statement, then we would have to agree with the poster that the first statement also was untrue!


    However, that second statement does NOT logically follow from the first statement, and hence, the poster's argument is invalid.
     
  11. Jul 9, 2006 #10
    I'm not good at this sort of stuff, I don't even know what => means, but the logic seems flawed to me also. However, it is not absurd to think that mathematics can be used to demonstrate the existence of something like a soul. Sorry to mention the mathematician George Spencer Brown yet again, but his book Laws of Form can be read as such a demonstration. Not a proof that we have a soul, for this word now has about twelve different interpretations, but something like a soul. Something more like the Buddhist idea of a pattern of impressions made on an underlying continuum of shared awareness.
     
    Last edited: Jul 9, 2006
  12. Jul 9, 2006 #11
    Isn't it the opposite? He thinks that the second statement doesn't follow from the first, because the second statement is not true.

    Also, does

    "IF something is conscious, THEN it is also alive"

    mean the same as

    "Something is conscious only if it's alive" ?

    Can one of these statements be true, and the other one false? Or do both of them have to be the same (true or false, logically speaking)?
     
    Last edited: Jul 9, 2006
  13. Jul 9, 2006 #12

    arildno

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    They mean the same thing.
     
  14. Jul 9, 2006 #13
    Ok, so what are you saying then - that the first statement can't be true because the second one is not true, or that the second one doesn't follow from the first one? And if the first one is not true, isn't it the whole point? e.g. to show that something doesn't have to be alive in order to be conscious?
     
  15. Jul 9, 2006 #14

    arildno

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    You should learn to read a perfectly clear text!
    "or that the second one doesn't follow from the first one"
    This is what I've said; the poster thought it did follow from the first stament.
     
  16. Jul 9, 2006 #15
    Please, don't get annoyed with me, I'm trying hard to keep up, trust me :(

    Anyway, I looked up the rule you're talking about http://www.math.csusb.edu/notes/logic/lognot/node2.html

    And there they say that the conditional statement p->q is equivalent to its contrapositive statement not-p -> not-q.
     
  17. Jul 9, 2006 #16

    arildno

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    No, it doesn't say that! Read the letters on that link once again.
     
  18. Jul 10, 2006 #17

    loseyourname

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    Is says that p->q is logically equivalent to ¬q->¬p, which is the reversal of what you read. Taking this back to the original argument presented, if consciousness implies that a given being is alive, then not being alive implies that the same being is not conscious.

    I'll go through the entire argument with you.

    As you can see, this isn't actually the case. C->A is not equivalent to ¬C->¬A. To illustrate this, we can use truth tables, as the author of this post later uses.

    Code (Text):

    C  A  C->A  ¬C->¬A

    T  T    T      T
    T  F    F      T
    F  T    T      F
    F  F    T      T
     
    As we see pretty quickly, they are not the same. In fact, the author's claim, that C->A implies ¬C->¬A is proven to be a contradiction by the third line of the truth table, in which the truth of C->A actually implies the falsehood of ¬C->¬A. This does not mean that both statements cannot be true, but the truth of one does not make logically necessary the truth of the other and a relationship of material implication is a contradiction.

    Let me give a non-abstracted example of why this relationship does not hold. Take the statement of material implication "If it is humid outside, I will have frizzy hair." Even without the aid of truth tables, we can pretty clearly see that the statement "If it is not humid outside, then I will not have frizzy hair" is not also true. There are a variety of reasons one might have frizzy hair, atmospheric humidity being only one.

    This argument falls victim to the same pitfall.

    I am not entirely certain what is meant by a human being a "closed system." We are obviously not. We eat, excrete, breathe, bleed, and absorb and expel material through our skin. Any living being requires a net input of free energy to carry on the anabolic processes necessary to stave off the pull of entropy and maintain the cellular organization that life requires. This has absolutely nothing to do with consciousness or brain activity in general.

    To the second statement, that being alive is not enough to produce consciousness, it is difficult to understand why the author thinks this is a statement of any controversy or significance. It is generally postulated by anyone that is not a panpsychist that many forms of life (plants, sponges, fungi) are not conscious. The tacit conclusion he seemingly wants to draw is that non-naturalistic factors must be at play in producing human consciousness, but he has not deduced this anywhere in the post you have quoted. This argument:

    P1. The state of being alive does not produce consciousness.
    C. Therefore, naturalistic forces do not produce consciousness.

    Is a clear non-sequitur. Naturalistic forces are not equivalent to being alive. To again use a rather banal example, consider walking. The vast majority of living organisms do not, and cannot, walk. Therefore, simply being alive is not enough to produce the ability to walk. Clearly, there is "something more" at play, in this case the presence of legs, feet, and the necessary muscular structures to use them and neural structures to maintain balance. There is certainly nothing supernatural at work.
     
    Last edited: Jul 13, 2006
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