What is Circular Reasoning?

by God_Delusion 36 Replies latest watchtower beliefs

  • bohm
    bohm

    mad dawg: "If finding a creature from today next to a dinosour falsifies evolution, you have a problem. There are many critters (alligators, mosquitoes, cockroaches, certain fish) that are found next to dinosours. Just that every time something falsifies evolution, an ad hoc excuse is created. So-called predictions are not the basis of science. In order for it to be science, it must be: measureable, verifieable and repeatable. As origens deals with history, neither idea qualifies as science."

    you are completely wrong

    a) Evolution does not predict alligators, mosquitoes, etc. have died out. read any introductory text about evolution to see why you are wrong. It does predict a number of things, for example that there will be some significant changes in their DNA, especially the non-coding parts. It even give some numbers on that based on mutation rates, population size, etc. that in principle can be tested (provided one could find ancient DNA).

    b) The rabbit and T-rex example is still relevant. i mentioned them because everything indicates rabbits evolved LATER than the dinosauers, and therefore they could not live together. Thats what makes the theory falsifiable and there is very little room for add-hoc explanations there. So instead of introducing a red herring with the alligator, you should perhaps focus on how this does not make the theory falsifiable. Heck, if you dont like the example, talkorigins has a list of 29 falsifiable claims made by evolution that has been posted here to death.

    c) Your definition of science is pretty lame. I can define 'wrong' to be anything that implies the existence of a God, but that would also be a stupid argument from definition. Science is ALL about making predictions, did you understand what i wrote about probabilities? Let me ask you this: Is it not correct to talk about the probability of eg. evolution or creation being true, rather than treating these as either completely true or false? if yes, do you disagree with the bayesian paradigm, or do you think i misapplies it?

    d) I think all creationists should read this scripture before getting themselves into trouble: Proverbs 18:13 "When anyone replies to a matter before he hears it, that is foolishness on his part, and a humiliation".

  • bohm
    bohm

    Perry: Ill bring beer - but you better be right and the steak is less than 18 mio. years old or i will go Richard Dawkins on your ass! ;-)

  • teel
    teel

    All I can say to this is that I don't like cucumber, and it's good that I don't like it, because if I'd like it i would eat it, but I hate it.

  • VM44
    VM44

    If A and B are statements that can be assigned True or False values, then a circular argument may be represented by the following symbolic notation.

    (A and B) implies B

    This is always true in Boolean logic.

  • Mad Dawg
    Mad Dawg

    Bhom said:

    mad dawg: "If finding a creature from today next to a dinosaur falsifies evolution, you have a problem. There are many critters (alligators, mosquitoes, cockroaches, certain fish) that are found next to dinosaurs. Just that every time something falsifies evolution, an ad hoc excuse is created. So-called predictions are not the basis of science. In order for it to be science, it must be: measureable, verifiable and repeatable. As origins deals with history, neither idea qualifies as science."

    you are completely wrong

    Really? Completely and totally? You should reread your own point d.

    a) Evolution does not predict alligators, mosquitoes, etc. have died out… I never said that evolution predicts extinctions. read any introductory text about evolution to see why you are wrong. You need to read your own point d again.

    It does predict a number of things, for example that there will be some significant changes in their DNA, especially the non-coding parts. It even give some numbers on that based on mutation rates, population size, etc. that in principle can be tested (provided one could find ancient DNA). Because we don’t have enough ancient DNA, we cannot draw any conclusions based on it. Therefore, this is an evolutionary prophecy in search of a fulfillment.

    b) The rabbit and T-rex example is still relevant. i mentioned them because everything indicates rabbits evolved LATER than the dinosauers, I mentioned the ‘gators and such because if we don’t find a particular known contemporary of the dinos side by side with the dinos, the lack of rabbits prove nothing.

    and therefore they could not live together. And here is the circular reasoning. I know that C supports my position because A and B do. How do I know that A supports my position? Because B and C do. How do I know that B supports my position? Because A and C do.

    talkorigins has a list of 29 falsifiable claims made by evolution ... This article addresses all 29 claims.

    c) Your definition of science is pretty lame. Lame? It is a standard overview of thescientific method.

    Science is ALL about making predictions, Only in that it provides some guidance on where to apply the scientific method. Evolutionary “predictions” are not predictions at all. They are bootstrap explanations to what has been previously observed in nature. From Talk Origins’ claim 1 of 29:

    Ø If universal common ancestry is true, then all organisms will have one or more traits in common. (How do you know? Prove that a unique form of life can’t arise.)

    Ø OMG! All organisms have something in common. We MUST have evolved! There can’t be any other explanation.

    Let me ask you this: Is it not correct to talk about the probability of eg. evolution or creation being true, Could you put a number to the probability?

    rather than treating these as either completely true or false? Is this an admission that evolution is at least partly false and creationism is at least partly right?

    if yes, do you disagree with the bayesian paradigm, or do you think i misapplies it? You misapplied it.

    d) I think all creationists should read this scripture before getting themselves into trouble: Proverbs 18:13 "When anyone replies to a matter before he hears it, that is foolishness on his part, and a humiliation". You would do well to heed your own advice here.

  • bohm
    bohm

    Mad Dawg: It got a little better, but not a lot.

    "I never said that evolution predicts extinctions."Good then we agree and i misunderstood your point about alligators. I thought you mentioned alligators because it had some impact on my claim that finding a bunny next to a T-rex would wreck havoc to evolution.

    "Because we don’t have enough ancient DNA, we cannot draw any conclusions based on it" True and quite unfortunate. But we have DNA from all living creatures and some extinct and it keep bringing more evidence in favor of evolution all the time.

    "And here is the circular reasoning.". Oh really? yes, the evolutionary tree is build on observations, ie fossils, but there is a lot more to it than that. We can see that mammals evolve, ie. change away from the dinos, and that the mamals become more rabbit-like the younger they are. A rabbit and a T-rex together would indeed wreck havoc to that, a gator and a dino do not. Furthermore, after all this work was done, genetics came along and offered yet another layer of proof.

    "Lame? It is a standard overview of thescientific method. ". Im sorry for my poor choice of word. The scientific method is the way science usually operate, ie. a method. What i am talking about here is how to use evidence to reject or accept a hypothesis. Thats why i am talking about bayes law and i think you mix these two up.

    I will review the 29 claims later. Perhaps you should post them as a topic on their own?

    NEXT POST: Fun with numbers.

  • bohm
    bohm

    (continued because jwnet ate my last post and i really hate when that happends).

    FUN WITH NUMBERS: First, let me tell you that i am not bringing probabilites into this discussion because i know a bit about them and want to show off. I do it because i think probability theory get way, waay to little when one discuss philosophy compared to logic because lets face it, logic is a rather unnatural abstraction.

    "do you disagree with the bayesian paradigm, or do you think i misapplies it? You misapplied it.". So i will go into details. Please point out where i err:

    First some more silly remarks: Because we cannot determine a number does not mean it does not exist. For example, the halting probability of an N-bit program is quite impossible to calculate to. Secondly, yes i happily admit that i just think there is a high probability that evolution is true and creation is false - there is no admission there. Are you really 100% sure?

    Now let me get to the guts of this discussion and where you claim i make a mistake. What I imagine is that we did some observation, O, and we want to see how that effect the probability that evolution E is true. So basically we want to calculate P(E | O) and compare it to our old belief in evolution, P(E). So by bayes law we calculate:

    P(E | O) / P(E) = P(O | E) / P(O)

    Lets simplify it a bit and say that "not E" is the same as creation being true, C. In that case we can margenalize over E and get:

    P(E | O) / P(E) = P(O | E) / [ P(O | E) P(E) + P(O | C) P(C) ]

    I hope i didnt loose to many but it will become very clear what this mean now:

    Lets take an example and say that O is the statement that all life share the same basic DNA blueprint (ie. your example) and lets imagine that an evolutionist and a creationist is presented that statement.

    The evolutionist will properly argue: "Well, life can certainly have originated more than once so it is possible the statement is not true. But its billions of years since life originated, so it is likely one kind of life would have evolved some superior trait, for example the ability to replicate quickly, early on and driven the other into extinction. In all cases a Mitochondrial-Eve style ARGUMENT (not observation!) show that all sexual animals must be related". So i will say that the evolutionist will say that P(O | E) is very high, lets just set it to 1 for the arguments sake.

    The creationist will properly argue: "God created all life according to their kinds. It never said he reused blueprints. Hmm. he might have in the case of animals, most of them seem somewhat similar. What about bacteria? dunno. Perhaps all fish and birds share a common trait, and all things on land a common trait, and all plants a common trait but not anything else?". My point is that HE CANNOT BE SURE BECAUSE THE BIBLE IS NOT SPECIFIC, AND THERE ARE NO A-PRIORI ARGUMENT WHY IT SHOULD BE TRUE. So he might choose some middle ground and say that P(O | C) = 0.5.

    Plugging this into our equation gives (using P(C) = 1-P(E)):

    P(E | O) / P(E) = P(O | E) / [ P(O | E) P(E) + P(O | C) P(C) ] = 1 / [P(E) + P(C)/2] = 2 / [ P(E) + 1]

    As you can see, no matter what we assign to P(E) it increase P(E|O)!. In fact it increase the belief more for the creationist, who originally think P(E) is quite low.

    As you can see what matters is that the evolutionist assign different probabilities to P(O | E / C), now how certain they are. And thats my entire point: nontrivial predictions about the world that turns out to be true is what increase the odds that the theory is true. In fact, i will challenge you to find anything else which will change the probability. That is why life is an appolegetic really does not make sence except for the appolectic himself: All that matters, as long the theory is self-consistent, is what it predicts about the world, and a nontrivial prediction cannot be taken away by a smart 'oh gez, carbon 14 might be wrong because of gods awsome powers' type of argument.

    You can nitpick on my argument, for example say that E and C are not the only options. Its true, but it will not really change the outcome, just make the notation more complicated.

  • BluesBrother
    BluesBrother

    I had some dark suspicions of circular reasoning by the WTS during the years that I was active, but shelved them because, hey! "The Truth is the truth, and we all know that don't we?" It is only since coming here that I have really appreciated it for what it is...It is something like the thread I was just reading by Terry on black and white reasoning. If you do not want to learn anything, you never will..

    BTW...WELCOME BACK GUMBY!!!!

  • Mad Dawg
    Mad Dawg

    Bohm said:

    First some more silly remarks: Because we cannot determine a number does not mean it does not exist.

    True. We should be able to determine a number within some margin of error. To claim there is a number and then say the sum of our knowledge of that number is comprised of the null set effectively negates the existence of that number.

    yes i happily admit that i just think there is a high probability that evolution is true and creation is false - there is no admission there.

    Let me see if I understand you here:

    Ø The probability of evolution being true is <1.

    Ø The probability of creationism being true is >0.

    Ø YET, you state you do not admit that evolution is partially false and creationism is partially true.

    Ø Would you agree that, given the first two statements, that “possibly” can be used instead of “partially” in the third statement above?

    Keep in mind that in point C of your earlier post you expressed a preference of probabilities “rather than treating these as either completely true or false”.

    Just wondering:

    Ø If a rabbit were found next to a T-Rex, would you then assign a possibility of zero to evolution?

    o Do you understand that the lack of rabbits proves nothing?

    o Would you simply say that rabbits evolved earlier than we thought?

    Ø Do you realize that all the DNA in the world tells us exactly nothing of the DNA of animals that exist only as fossils?

    Ø What is this talk of genetic proof when you claim there are only probabilities?

    Ø The scientific method requires that something be observable, measurable, and reproducible.

    o Everyone agrees that there is at least a small degree of change in organisms. This does not prove horses evolved from dogs. Such a large degree of change has never been observed.

    o Probability applies to historical events.

    o Historical events cannot be tested.

    "Well, life can certainly have originated more than once so it is possible the statement is not true. But its billions of years since life originated, so it is likely one kind of life would have evolved some superior trait, for example the ability to replicate quickly, early on and driven the other into extinction.

    Ummm… earlier you stated that evolution does not require the extinction of earlier life forms, are you now saying it does? How can we have organisms with similar traits today it the superior ones “drive(n) the other into extinction”? Sounds like an ad hoc explanation for what is seen in nature.

    In all cases a Mitochondrial-Eve style ARGUMENT (not observation!) show that all sexual animals must be related".

    Mitochondrial Eve deals only with humans – nothing else. Other species would have their own Mitochondrial Eve’s.

    In fact, i will challenge you to find anything else which will change the probability.

    You really make this too easy. Because you arbitrarily assigned values to the variables in the equation, all that needs to be done is to assign different, equally arbitrary, values. It would also help you to understand what they say about common design.

    You would do well to actually read up on what creationists say about c 14 rather than trying to argue against a caricature of their arguments.

  • bohm
    bohm

    Mad Dawg: "To claim there is a number and then say the sum of our knowledge of that number is comprised of the null set effectively negates the existence of that number."

    If you are saying that the probability does not exists, you are rejecting the entire bayesian framework. I know an entire department who will be out of work at my university!. If you are saying it exist, but the fact i do not assign a value to it - in principle i can, but it would be subjective - somewhat negates my argument. Well, if you reread what i said i am only talking about processes which increases or decreases the probability, that does not depend on actually knowing its value. (and just to be really obnoxious: i used the halting probability for an n-bit program specifically because it is an uncomputeable number so good luck finding a value for that!)

    Let me see if I understand you here:

    Ø The probability of evolution being true is <1.

    Ø The probability of creationism being true is >0.

    Ø YET, you state you do not admit that evolution is partially false and creationism is partially true.

    It is allmost correct but you are missing the essense: If i flip a coin but do not look at it, i will assign a probability of 1/2 to it being tails and 1/2 to it being heads. That does not mean it is partially heads, right? I am sorry if i am being anal because perhaps we are just using different words for the same things, but we are talking about math so it matters that we are exact. Regarding your fourth statement: I will say that the probability that creation is true is not 0, so i am not excluding that possibility. Do you assign a probability of 0 to evolution being true?

    "If a rabbit were found next to a T-Rex, would you then assign a possibility of zero to evolution?".Strictly speaking: no. but i would reject evolution as we know it as framework for understanding how has changed on this planet. I would most likely believe some alien entity had had a hand in evolution, and i would very seriously consider if that entity was God.

    "Do you understand that the lack of rabbits proves nothing?"That is exactly the point i showed with the calculation, so yes, i think understand that! Do you understand the points i was trying to make, and if yes, why are you restating them as questions to me?

    "Do you realize that all the DNA in the world tells us exactly nothing of the DNA of animals that exist only as fossils?" Assuming evolution it does. Which can be turned into predictions about dna of current animals. Which can be observed. which i prooved for you increase the probability of evolution being true.

    "What is this talk of genetic proof when you claim there are only probabilities?"Im sorry if i said proof, that was a mistake. I mean something that raise the probability very very much. Its very poor language on my part :-(.

    "The scientific method requires that something be observable, measurable, and reproducible.

    o Everyone agrees that there is at least a small degree of change in organisms. This does not prove horses evolved from dogs. Such a large degree of change has never been observed.

    o Probability applies to historical events.

    o Historical events cannot be tested."

    Again, you do not understand me at all! the observations need to be reproducible, yes! but if we follow through your line of reasoning, we cannot say ANYTHING about the evolution of the universe since it is all history! You are advancing an argument per definition where you want to define science such that evolution is not science, and then claim victory.

    I am talking about basic probability theory, the probability that evolution is true given evidence. You can make a definition of science that exclude evolution, geology and a large part of cosmology, but that does not change the point that certain observations, depending on how likely they are given the different theories, will increase or decrease the probability of evolution being true. Thats my point. Thats what YOU wrote was a misapplication of bayesian probability. Please point out where i am wrong.

    Ummm… earlier you stated that evolution does not require the extinction of earlier life forms, are you now saying it does? How can we have organisms with similar traits today it the superior ones “drive(n) the other into extinction”? Sounds like an ad hoc explanation for what is seen in nature.

    These are standard creationist arguments and i wont address them here, i will just note i said no such thing, all i am saying is that in an evolutionary process most species will go extinct and those who hang around will experience a lot of genetic drift.

    Mitochondrial Eve deals only with humans – nothing else. Other species would have their own Mitochondrial Eve’s.

    Well, read about the mitochondrial eve, i started a thread where i explained it to some details earlier. The same argument can be used on an inter-species level. You are just plain wrong, at least assuming evolution is true (and before you hit me on circular logic: i was calculatin P(O|E), so i specifically assumed evolution to be true there).

    You really make this too easy. Because you arbitrarily assigned values to the variables in the equation, all that needs to be done is to assign different, equally arbitrary, values. It would also help you to understand what they say about common design.

    Now do i... In the bayesian paradigme priors are subjective (unless we are talking very easy cases where symmetry arguments can be used), how we combine probabilities to affect the outcome is not. That being said, please write out in standard notation how you will do inference based on observations in a different way than i proposed. You claim its easy, i am not saying it cannot be done, i am just saing i cant really think of a way and i would like to be proved wrong.

    And by the way. I doubt common design has anything to say about a pure math topic.

    You would do well to actually read up on what creationists say about c 14 rather than trying to argue against a caricature of their arguments.

    Yah it was a caricature. My point is that the creationists explanations rarely has any predictive power, but the evolutionists often have. For example, given all the theories on how C14 dating is wrong, can you think of one single nontrivial prediction that give rise to about the world?

    Its not so bad your grand-grand-grand mom was a monkey. They have a much more healthy relationship to being naked than we do.

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