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Thread: Philisophical question about logic...

  1. #1

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    Cool Philisophical question about logic...

    There are sentances that can be constructed in language that appear contradictory but are not, technically speaking, contradictions.

    Such as:

    "There is a fire in the room. I do not believe there is a fire in the room".

    It is not contradiction (from the perspective of formal logic) in that it doesn't take the form "B. And not B." but linguistically, it is.

    Which raises the question, does formal logic fail to encapsulate lingustic logic?

    Or perhaps the above example can somehow be reduced to the form "B. And not B."?

    The first sentence is a statement of fact and the second sentance is a statement of one's own belief. A Solipsist would argue that we are not qualified to make statements of fact but only speak of our own perception. Therefore, is the first sentance not equivilent to "(I believe) there is a fire in the room"?

    Is "I believe there is a fire in the room" semantically equivillent to "There is a fire in the room". They don't appear to be but then you wouldn't say there is a fire in the room unless you believed there is a fire in the room?
    Everything I say is either loose interpretation of dubious facts or idle speculation rooted in irrational sentiment.

  2. #2
    Lively Member Behemoth's Avatar
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    I have been informed that there is a fire in the room. Somebody put the bastard thing out!
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    Lively Member Wally Pipp's Avatar
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    a philosophical addendum (not unimportant) : is it my room ?
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    Monday Morning Lunatic parksie's Avatar
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    Perhaps the linguistics fails to capture the necessary logic.
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    Randalf the Red honeybee's Avatar
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    Well ...

    Originally posted by simonm
    "There is a fire in the room. I do not believe there is a fire in the room".
    It is not contradiction (from the perspective of formal logic) in that it doesn't take the form "B. And not B." but linguistically, it is.
    It's a contradiction if it comes from the same person's mouth in "the same breath" so to speak. If it's not, the person is a friggin' liar.

    If you take the sentence "There is a fire in the room" equal to the sentence "I believe there's a fire in the room", you are actually trying to talk the objective/subjective reality thing here

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    Parksie
    Perhaps the linguistics fails to capture the necessary logic.
    What's the point of formal logic if it fails to capture the intracacies of human language?

    Honeybee
    If you take the sentence "There is a fire in the room" equal to the sentence "I believe there's a fire in the room", you are actually trying to talk the objective/subjective reality thing here
    But that's the point. Are they semantically equivillent or are they different. If they are different then we have a linguistic contradiction which is not recognised by formal logic.
    Everything I say is either loose interpretation of dubious facts or idle speculation rooted in irrational sentiment.

  7. #7
    Randalf the Red honeybee's Avatar
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    Well ...

    Originally posted by simonm
    But that's the point. Are they semantically equivillent or are they different. If they are different then we have a linguistic contradiction which is not recognised by formal logic.
    They definitely are different. When you say "There is a fire in the room.", you are describing a fact which can be corroborated by other evidence. When you say "I believe there is a fire in the room.", you are giving your interpretation of some fact. This fact may or may not be that there's a fire in the room. Thus the first sentence is a fact, whereas the second is an interpretation. Going by the arguments about the objective/subjective realities, you can safely assume these statements to be different.

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    Honeybee
    They definitely are different. When you say "There is a fire in the room.", you are describing a fact which can be corroborated by other evidence.
    You believe that it can be corroborated by other evidence but, if you believed that there is a fire in the room, likewise, you would believe that other evidence would corroborate that asserted fact.
    When you say "I believe there is a fire in the room.", you are giving your interpretation of some fact.
    Isn't that really the same thing?

    I mean, we don't directly experience an objective reality, do we? Only our perceptions of it directly impinge on our consiousness so any synthetic statements we make can only really be about our own perception, right?
    This fact may or may not be that there's a fire in the room. Thus the first sentence is a fact, whereas the second is an interpretation. Going by the arguments about the objective/subjective realities, you can safely assume these statements to be different.
    But how can we know it's a fact? You only believe it's a fact, right? You could be wrong...
    Everything I say is either loose interpretation of dubious facts or idle speculation rooted in irrational sentiment.

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    Lively Member Behemoth's Avatar
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    when you state "there is a fire in the room", you are not merely stating a belief that there is a fire in the room, but that your belief is so strong that you are unlikely to change that belief. The likelyhood is that you have seen it or been informed by another reliable source. When you state "I believe...", you are diluting that original belief. It is no longer so strongly established, and must be described as such.

    the first statement would be "I believe there is a fire in the room", and the second "I believe I believe there is a fire in the room"...
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    Lively Member Behemoth's Avatar
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    in summary - "there is a fire in the room" is such a strongly held belief that the belief part is assumed. "I believe..." implies that the belief is not as strong and thus requires mention.
    If tomorrow never shows
    I want you all to know
    that I loved you all
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    And I had myself a ball
    I've wasted so much precious time
    I've been skating along these fine lines
    Now these weeds have grown where the sun once shown
    and my life has passed me by...

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    http://www.galah.net/

  11. #11

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    Behemoth
    in summary - "there is a fire in the room" is such a strongly held belief that the belief part is assumed. "I believe..." implies that the belief is not as strong and thus requires mention.
    So you're saying that the statements reflect different intensities of certainty?

    The fact still remains that "There is a fire in the room" is not a statement (explicitly) about our belief but is a statement about reality itself. But, you think that "(I believe)" implicitly prefixes the statement so that really, it is not a statement about reality itself but about our own perception?
    Everything I say is either loose interpretation of dubious facts or idle speculation rooted in irrational sentiment.

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    Lively Member Behemoth's Avatar
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    only those that have intimately contemplated the nature of reality would say so, but yes.
    If tomorrow never shows
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    And I had myself a ball
    I've wasted so much precious time
    I've been skating along these fine lines
    Now these weeds have grown where the sun once shown
    and my life has passed me by...

    http://www20.brinkster.com/behemoth

    http://www.galah.net/

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    Lively Member Wally Pipp's Avatar
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    The main trouble is that the three tier set that is linguistics is far too complex to pour into simple logical formulas.

    Syntax (how a message is constructed)
    Semantics (what a message means and how it is expressed)
    Pragmatics (how a message is used in a certain contex)

    These three are rather difficult to pour into logical schemes. Certainly if we consider that with different semantics the whole message changes whereas the syntax and/or pragmatics stay the same. Same goes for pragmatics of course.

    How do you formulate logic of such a complex, flexible system incredibly rich in variations and undertones ?
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    I guess that some would claim (such as Wittgenstein) that by reducing arguments to formal logic, we are losing something that may allow us to draw false conclusions.
    Everything I say is either loose interpretation of dubious facts or idle speculation rooted in irrational sentiment.

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    Lively Member Wally Pipp's Avatar
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    example (simple one) :

    the expression "I'm a pineapple"

    a) when used f.i. in a play about a pineapple we know it's a metaphore inherent to the play. Pineapple's don't talk.
    b) when used in a children's book it is a description of a fruit.
    c) when said by a child it's a part of the learning process of the child trying to understand the distinctions in grammar
    d) when posted loosely (say Golden Chair) it's a non sequitur with no actual meaning other than novelty, weirdness and confusion to the reader.

    Yet in all cases it's the same syntax, the same words, the same expression.

    How do you go about making logic out of that ? I think it's a gargantuan task really.
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    Wally

    Ah, but the logic of contradiction should transcend that, right? "I am a pineapple. I am not a pineapple" would be a contradiction in any of the contexts you listed.

    "I am a pineapple. I don't believe that I am a pineapple"

    That would also be a constradiction in most contexts, however, in this context:
    a) when used f.i. in a play about a pineapple we know it's a metaphore inherent to the play. Pineapple's don't talk.
    It's actually a valid set of statements...
    Everything I say is either loose interpretation of dubious facts or idle speculation rooted in irrational sentiment.

  17. #17
    Lively Member Wally Pipp's Avatar
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    Not really. If "I'm a pineapple. I'm not a pineapple" is said by 2 different persons we have a different setting than when it's said by one person.
    Second, if one person says it but doesn't make a connection between the sentences then there's no logic involved. It's only when he says them in a succession of statements.
    The same with the "there is ... I don't believe" set of statements. Are they said together or in separate contexts ? Are they spoken by one or 2 persons ? Does expression one have any bearing on expression 2 ?

    That's another trouble with linguistics : what you hear and read may not always have the same meaning.

    If someone says to you "I'm having a ball" over the telephone. When reviewed in itself the expression can have various meanings. Is he having a party ? Is he having fun ? Is he choosing a ball in a toy store as a present ? Is he choosing some kind of drink that is called 'a ball' ?
    You can't know for sure until you are informed of the rest of the situation. You can't just plunk 2 sentences after each other and expect someone to draw a logical conclusion. Linguistics don't work that way. Not to mention irony, sarcasm, inadequate knowledge or non sequiturs.
    You need more than just two juxtaposed expressions, you always need to consider pragmatics (i.e. in what context is the expression used ?)
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    Wally
    Not really. If "I'm a pineapple. I'm not a pineapple" is said by 2 different persons we have a different setting than when it's said by one person.
    But it's enclosed in a single set of quotation marks so I would argue that it's explicit that it's one entity stating it.
    Second, if one person says it but doesn't make a connection between the sentences then there's no logic involved. It's only when he says them in a succession of statements.
    Isn't the mere fact that they are in succession indicitive of their conjunction?

    Anyway, the point with the statement "There is a fire in the room. I don't believe there is a fire in the room", is that even if you make every effort to establish context, it is still not a contradiction when represented formally, yet common sense tells us it is.
    Everything I say is either loose interpretation of dubious facts or idle speculation rooted in irrational sentiment.

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    Lively Member Wally Pipp's Avatar
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    that's because common sense is rooted in pragmatics. It adds the context of the situation which is what the formal logical evaluation doesn't do.
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    So Unbanned DiGiTaIErRoR's Avatar
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    Well.

    If they're both spoken. Then they're both belief.

    And those beliefs would contradict. Just because you say I believe instead of not doing do doesn't really make a difference.

    I.e.

    I'm posting on this board. I believe I'm posting on this board.

    They're saying the same thing.

    Can you believe I'm posting on this board. Yes I can believe it.

    Unless the "There's a fire in the room." is a given absolute.

    Wait... what's the question again?

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    DiGiTaIErRoR
    If they're both spoken. Then they're both belief.
    Indeed, but one is spoken about reality itself and the other about a belief in reality.

    You could claim that he is not qualified to speak about the nature of reality directly, only his perception of it, but you cannot prove that. He would not be forced to accept that.

    On the face of it, they are statements about two distint and different things yet somehow, they contradict.
    Everything I say is either loose interpretation of dubious facts or idle speculation rooted in irrational sentiment.

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    transcendental analytic kedaman's Avatar
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    Simon

    phrases that contain self-references are not statements. "I" in this case is not a self reference, however "There is a fire in the room. I do not believe there is a fire in the room. I wrote this statement"
    is not a conjunction of three statements because the third phrase "I wrote this statement" has the self reference, "this" and is not a statement. In other words in everything you write you cannot state that you are the author of what you are saying - but this goes for everything that has to do with the statement itself.

    "There is a fire in the room. I do not believe there is a fire in the room."
    There is no implication that "I" in this statement wrote this statement in the first place. It's still a logical reasoning.
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  23. #23
    Randalf the Red honeybee's Avatar
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    Well ...

    Originally posted by simonm
    You believe that it can be corroborated by other evidence but, if you believed that there is a fire in the room, likewise, you would believe that other evidence would corroborate that asserted fact.

    Isn't that really the same thing?

    I mean, we don't directly experience an objective reality, do we? Only our perceptions of it directly impinge on our consiousness so any synthetic statements we make can only really be about our own perception, right?

    But how can we know it's a fact? You only believe it's a fact, right? You could be wrong...
    OK, here's an example:

    A man rushes into a police station and says to the officer on duty,
    Man: Hurry, there's been a murder on the 23rd street!
    Officer: Oh, who's been murdered?
    Man: I dunno. I saw a body lying in a pool of blood on the kerb.
    Officer: Was it a man or a woman?
    Man: I don't know. I didn't look very closely.
    Officer: Are you sure whoever it is, is dead?
    Man: Well, since the body was motionless and there was a lot of blood it must have been dead.
    Officer: Did you see anybody else around?
    Man: No, the street was deserted.
    Officer: How do you know, then, that it's a murder?
    Man: Well, to be frank, I thought it must be murder. How else could there be such a big pool of blood there?
    Officer: Which street did you say it was?
    Man: The 23rd street, which has got The Mall on it.
    Officer: Oh, yes, I know that place. Let's go and check then.
    From the above conversation, you can see that the officer knows for a fact only the thing that there's a body lying on the 23rd street in a pool of blood. There are no definite answers to whether the body is that of a man or a woman, or dead or alive, murder or some other cause in case of death.

    You could argue that since all the man has said are his beliefs about the situation, they cannot be taken as facts. But the cross-examination by the officer can establish certain points as facts. The fact that the incident actually happened on the 23rd street. The man and the officer both are in agreement that the place known as the 23rd street is associated with another place known as The Mall. Under practical and sensible assumptions, we can conclude that the incident occured on the 23rd street is a fact since both the persons believe the same.

    There are other points which the officer finds out MAY NOT be facts. For e.g. the body may not be dead. Because the man didn't check it himself. He saw the body lying and drew his own conclusion, which has not been verified. If the man had verified this by checking the pulse or describing the body, for e.g. "the throat was slit open with a long sharp knife which is stuck in the body's heart", or "the body didn't have a head" could have established for a fact that the body to be dead. Here the man and the officer would both be in agreement that the method applied to verify if the body is dead or not is sound. Therefore it would be a fact.

    Then there are points which are yet to be ascertained such as the gender of the body and the reason for death, assuming it's a death.

    I think if two or more persons agree on a particular interpretation of an event, that could be taken as a fact. For e.g. in the above conversation the officer doesn't agree with the man that the body is dead, because he is not satisfied a mere sight of the body in a pool of blood is conclusive evidence of death. So that's not a fact. However he agrees the incident occured on the 23rd street because the man has used The Mall as a reference which has been accepted by the officer.

    Coming to the fire in the room, if a person says "There is a fire in the room", unless you have reason to believe otherwise, this statement has to be taken as a fact. You can cross-examine the person or gather other evidence to verify whether it really is a fact. For e.g. you can ask some other people. If another person replies that there is a fire in the room, the fact has been corroborated. If you can't get other opinions, you can cross-examine the person or gather physical evidence.

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  24. #24
    Kitten CornedBee's Avatar
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    Simon
    You could claim that he is not qualified to speak about the nature of reality directly, only his perception of it, but you cannot prove that. He would not be forced to accept that.
    Ok, so we have two cases:
    a) The person is not qualified to make objective statements about reality.
    This is the more likely case. Here we must use Wally's views with "There is a fire in the room." being a certain belief. Therefore we can say that it is a direct negation of "I don't believe there's a fire in the room.". This person obviously isn't logical and therefore formal logic shouldn't be applied to his sentences.

    b) The person is qualified to make objective statements about reality.
    In this case the person refuses to believe something he himself knows is absolutly wrong. This person obviously isn't logical either.
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  25. #25
    transcendental analytic kedaman's Avatar
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    with the same reasoning you could say that nobody is logical, and that if you assumed objective reality, that they don't exist either
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  26. #26
    Lively Member Wally Pipp's Avatar
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    As stated before, humans haven't got the right 'equipment' to be objective about reality.
    It's always seen through your own senses, your own interpretations.

    It's the misty house thing again : If you come to the place for the first time and you can't see the house and someone says "there is a house over there", you are not inclined to believe it because you don't see it but further investigation will show you the house.

    So our perception of reality changes as the pragmatics of the statement changes by new data.
    We are too dependant on our insufficient perceptions to be objective about the nature of reality. As it is we can't say it exists in one form or another as we can't trust our perceptions to be right at all times.
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  27. #27
    Kitten CornedBee's Avatar
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    Originally posted by kedaman
    with the same reasoning you could say that nobody is logical, and that if you assumed objective reality, that they don't exist either
    How would you go about that?
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  28. #28
    transcendental analytic kedaman's Avatar
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    sorry, I misread your reasoning.
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