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Origin of logic

  1. Feb 3, 2007 #1
    How does logic arise and when/where did it first?
  2. jcsd
  3. Feb 3, 2007 #2
  4. Feb 3, 2007 #3
    Could u quote a relevant part? In the section about history of logic it appears to only speak of logic in humans, so did logic first arise in humans?
  5. Feb 3, 2007 #4
    Well, I wasn't there when it first happened. :smile:

    Since logic is a system of reasoning, it had to arise in something equipped with reasoning abilities. Aliens are not ruled out. But why do you ask, would you expect logic from inanimate objects?
  6. Feb 4, 2007 #5
    Some people think that logic always existed, and that humans simple discovered it. Others think logic has no origin:

    Personally, and i dont know much about logic, i think it arises in a mind.
  7. Feb 4, 2007 #6
    Here's a thought. Try "mathematics" instead of "logic". It's just another system of reasoning and its rules apply to concepts very similar to logical propositions. Better yet, simplify and only address "arithmetic" or even just "addition". It's the same idea, with the benefit that you know it very well. See what answer you would get by rewording your original question: "How does addition arise and when/where did it first?"
  8. Feb 4, 2007 #7
    Hmm i dont think it simplifies the question. What about all the scientists looking for a mathematical equation to describe the universe. If the equation exists, it would mean mathematics already existed inherently in nature before us. The fact that we 'invented' it was then just a result from us observing what was already present.

    Addition also, we know it because we observe it.

    Are those the simpler answers u also had in mind?
  9. Feb 4, 2007 #8
    Truly, I'm not sure, I only have a suspicion that remains wide open to discussion. I suspect that it's only a matter of definition, little more than an agreement. I also think the question simplifies even further to "how do numbers arise" at which point we need to decide if numbers occur in nature or if they are a man-made concept. I think the answer would then extend back to addition, arithmetics, mathematics and logic.

    So now I ask: does "2" exist in nature? Is a sentient being required for "2" to exist or would "2" exist even if no consciousness were aware of it?

    Being sentient, I have a mental representation of "2 apples". But then, "2 apples" is merely my chosen separation of these objects from all other apples that truly exist. I do this in my head. In reality there are innumerable quantities of apples so "2 apples" is merely my decision to ignore all the other ones for my immediate purpose.

    I also note that "2" can be applied to all sorts of objects, not only apples. But when you look at an apple, you don't see "2". When you look at a pile of rocks, you don't see "2" either. In fact, you don't find "2" anywhere except when you purposely isolate specific items in such a way that they correspond to the concept of "2".

    So it seems to me that "2" is not a natural phenomenon. If a number is a man-made concept then so is addition. If addition is man-made then so it arithmetic. And so on.

    Over to you.
  10. Feb 4, 2007 #9


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    What can be thought of as a '2' has certain properties, namely those of the number 2. If you have a collection of, say, apples, and you choose to quantify over apples in that collection of stuff, you might say that you have a collection of 2 apples, which means that your apples-collection is a 2-instance, or your collection is a 2-instance when quantifying over apples.

    Does an apple-collection exist without a human mind? I think so, because we can think about that analogy now and understand what it is, even though in the analogy there is no human mind. My thinking is that there needn't be an observer in that system, that Mt Everest was the tallest mountain at least for a time before it was discovered. Perhaps this is a word game.
  11. Feb 4, 2007 #10
    Jack: Show me "2".
    Jane: There are two apples on the table...
    Jack: Those are apples. Show me "2".
    Jane: Well, the pair of them makes two.
    Jack: But I don't see 2, all I see is apples.
    Jane: [Takes away the apples and puts 2 quarters on the table.] There, these are two quarters.
    Jack: There you go again, with quarters this time.
    Jane: But there are exactly 2 of them!
    Jack: What about the one in my pocket?
    Jane: No, no. "2" means those on the table.
    Jack: What does the table have to do with 2?
    Jane: The table doesn't matter. What matters is that there are 2 coins on it.
    Jack: But why don't you care about the one in my pocket?
    Jane: Because it's not on the table.
    Jack: Ah-ha, so the table does matter.
    Jane: [Impatient.] No, not the table, just the fact that the coins are on it.
    Jack: So "2" is whatever is on the table? [As he puts his third coin on the table.]
    Jane: Well, now it's 3, not 2.
    Jack: You're contradicting yourself.
    Jane: Not at all, you've changed what's on the table.
    Jack: You said what matters is that they are on the table.
    Jane: [Pulling her hair.] Everybody knows what 2 means!
    Jack: So "2" is just something people mean?
    Jane: Yes, "2" is a common agreement.
    Jack: I disagree.
    Jane: [Walking away.] I agree to disagree.
    Jack: [Shouting.] Has anyone seen 2?
    Last edited: Feb 4, 2007
  12. Feb 7, 2007 #11
    Logic is an abstraction of cause and effect, the most fundamental principle in the objective world. If this, then that. When taken out of the time domain, it can be applied to ideas by recognizing that one, a premise, implies another, a conclusion.
  13. Feb 8, 2007 #12
    Cause and effect is philosophical stance nothing inherent in nature. To abstract logic from cause and effect presupposes the thing which you are trying to abstract. This certainly is not case. Actually, from study of developing/"primitive" cultures we learn that its at best it is far more complicated.
    In the world of "objects" one almost feels that logic is forced on him/her. However, some cultures do not even 'see' object world. The forest might be one spirit, there the trees are seen by eyes as separate but not by the mind. The desert may be god, ...etc. Therefore, the part or separate objects we perceive is already our "bias". Other ppl may not see separate parts where we do see them, or their relationships might be totally different [not causual in our sense of the word].
  14. Feb 8, 2007 #13
    Cause-and-effect must be understood by any culture that operates successfully in the world. The primitive cultures you mention may well have non-causal ideas, but it would be hard for them to hunt or grow crops without some notion of causality. The appreciation of cause and effect gives rise to orderly thinking and that has led to logic.
  15. Feb 8, 2007 #14
    You are oversimplifying the philosophical thought here. Cause and effect as you state it is philosophical stance of materialism/scientism. Every culture knows that there are effects of their actions, etc. However, the proposed cause-and-effect view of nature is only philosophical one.

    Before somebody comes out saying some nonsense, Im not denying cause and effect. However, cause-and-effect view of world as it is commonly applied today is philosophical stance.
  16. Feb 8, 2007 #15
    Can any process of cause and effect be used as a process for computation?

    What about the validity of the converse?
    Cause and effect is a consequence of logic, the way the mind maps the objective world.
  17. Feb 8, 2007 #16
    The perception of causality is indeed a mental "mapping." But that perception, in itself, is primitive to logic. Logic not only applies to time sequences of events in the physical world, but also to ideas that are independent of time. That is where the abstraction comes in.

    Computers use electrical causal sequences. Put a set of numbers in, a resultant set of numbers comes out. The basic operation: the flip of one bit causies the flip of another.
  18. May 3, 2007 #17
    origin of logic in a philosopher's argument.

    This came up in the Wikipedia entry on logic,

    "...Logic arose ... from a concern with correctness of argumentation. The conception of logic as the study of argument is historically fundamental, and was how the founders of distinct traditions of logic, namely Plato and Aristotle, conceived of logic..."

    Were either Plato or Aristotle correct in thinking logic is about "correct argumentation" or "argumentation" at all? I don't mean to suppose that it has to do with the other options proposed by Kant as being about judgement, and so on, as discussed in wikipedia. I'm just wondering whether they got it wrong. I would think that Kant may have argued that his view was not all that divergent from the older Greek idea about argument.

    I'm thinking that argument is about controversies, positions, and support for those positions. These are the three properties that distinguish arguments. If you don't have them, then, I'm supposing, you don't have an argument. Now, logical arguments, or what are called logical arguments, are made up of only positions and their support. I'm told that logical arguments cannot be about controversies without becoming something else. They become confused with rhetorical arguments that involve themselves in issues or what's considered the arguers' "psychological" concerns.

    However, as logical arguments do not involve all the properties of arguments, then they are not arguments. One might call them, "attenuated arguments," or "incomplete arguments." Whatever you call them, they aren't really arguments.

    So, Plato and Aristotle were wrong to claim that they were talking about the correctness of argumentation. Logical arguments aren't about argument at all.
  19. May 3, 2007 #18
    If you are asking when it arose historically i'm gonna have to go with Aristotle.
  20. Oct 29, 2008 #19
    Again, there is a difference between asking about the origins of something, like asking where something came from, where was he or she born, where did the outbreak originate, and so on, and asking about the "genesis" or argument for something. I can ask about where or when people first started asking about whether Obama is a socialist, or a Muslim, wondering if it was on a website, a Rebublican think tank, and so on. Or I can ask about how the issue was first thought up. Did someone see something in some old records or talk to someone who knew Obama when he was younger, that made them think that he might now be tainted in this way. Or, did the idea come up in a discussion about possible ways to smear his character that could not come back to haunt the McCain campaign? The two questions are different. With the question of the genesis of these questions one could ask whether the claims they make about Obama are justified. Is there any truth behind them?

    I want to say we can ask the same questions about logic or logical argument. We can ask when or where logic or logical argument was first discussed or employed. This may be something we would find difficult to do because records of early discussions or usages probably do not now exist, if they ever did. On the other hand, we could ask how the idea of logic or logical argument came about. Is there some argument for it which one can examine and critique? Basically, though, the questions I'd ask are whether it is what it is claimed to be, a way of thinking? Is there any justification for the claims made about it?

    I am skeptical about the idea that reason is a matter of logical argument. I don't think there is any "way of thinking" that we understand as logic which stands in contrast with other ways of thinking, some we call rhetoric, for example.

    This is not to say that we don't use logic to design computer programming. I just doubt that thinking or reason has anything to do with logical argument.
  21. Oct 30, 2008 #20
    Argh... I wish I saw this thread before making my own.

    I am not an expert in history, but from the courses I've taken logic really was discovered by the Greeks. Now surely, people were innately logical probably back as far as caveman. A lot of laws and religions had elements of logic too. But it was the greeks who explicitly analyzed argument and the different methods of persuasion. A lot of the mathematics the early greek geometers worked on was already well known in Africa, notably Egypt. But it was the greeks who proved all the results, something no one was concerned with at that time.

    So while logic may have existed since the dawn of men, it was the likes of Plato and Aristotle who wrote about it and hence they get the credit. Aristotle gave us the first formal system in his analytics, which surprisingly hasn't changed much since.
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