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I am not well versed into how these logical fallacies are supposed to be applied. Everyone is operating with imperfect information, so no implication will ever

• pessimizer 6y ago
  Determinations of chance aren't material, they're a matter of perspective and a tool to use when making decisions. The chance that a wrong proof is correct is 0%, and the chance that a correct proof is correct is 100%, no matter what any selection of Fields medalists feel about it. Whether, when you're making a business decision, you go with the lone whacko or the Fields medalists is a different question.
• nkozyra 6y ago
  Argumentative logical fallacies apply to conclusions/truths, not suspicions or intuitions. They're meant to do exactly what you are asking for here: eliminate a binary rule from deduction.
• syops 6y ago
  An argument can be logically sound but with a false conclusion. An argument can be logically invalid but with a correct conclusion. The role of logical fallacies is to point out unsound reasoning. They don’t demonstrate veracity or lack thereof. Regarding the appeal to authority fallacy you mentioned. I personally do not believe this is a fallacy. I do agree that the appeal to false authority is a fallacy. We all have to rely on the expertise of others for much of what we believe to be true. Of course said beliefs might be wrong but relying on expert knowledge is not a fallacy in and of itself in my opinion.
  • MaxBarraclough 6y ago
    > An argument can be logically sound but with a false conclusion. That doesn't sound right. An argument is sound iff it is logically valid and its premises are true, right? From Wikipedia: > In deductive reasoning, a sound argument is an argument that is both valid, and all of whose premises are true (and as a consequence its conclusion is true as well) https://en.wikipedia.org/wiki/Soundness#Definition https://en.wikipedia.org/wiki/Soundness#Definition
    • syops 6y ago
      I guess it comes down meaning of “sound”. Let me be more specific. An argument can correctly use the rules of logic and have an incorrect conclusion. This can happen if some of the premises are false. For example: All men are immortal. Socrates is a man. Therefore Socrates is immortal. The rules of logic have been correctly followed but the conclusion is false.
      • tpoacher 6y ago
        You mean valid. Not sound. By definition if an argument is sound, it is also valid (but not the reverse). And by definition if an argument is sound, then its conclusions are true. I think you're just mixing up the terminology a bit.
        • syops 6y ago
          Well I did use logically sound and not sound argument. I personally don’t see a difference in logically sound and logically valid but I clarified things in my previous post.
          • MaxBarraclough 6y ago
            > I personally don’t see a difference in logically sound and logically valid They aren't the same. These are standard terms in logic, as explained in the Wikipedia article.
• prof-dr-ir 6y ago
  Nicely put. Maybe it helps to think of the purpose of those conversations where pointing out logical fallacies might help? Such conversations are almost always about changing someone's view of the world - sometimes through debate, where conflicting positions are taken and argued upon, and sometimes simply because someone (e.g. you) asks for a clarification in order to know which position to take. So I think that the idea is that people can at least take well-reasoned positions, not necessarily equal positions, in a world that is not black and white. The list of fallacies can then be a useful guide to judge the persuasiveness of the arguments of the different sides, including of course your own arguments, and to help you see whether a position might need to change because it is not well-reasoned. In your example, I can say "I trust Fields Medallists" and therefore judge the proof to be likely wrong. That is a valid position to take. You may say that "the author of the proof is a very talented mathematician" so the proof is likely right, which would be equally valid. What we cannot do, without further information, is to claim that the proof must with absolute certainty be right or wrong - that I believe would be the fallacy here.
• duedl0r 6y ago
  "appeal to authority" is a good example in our current situation. How many doctors are talking crap about Covid? Here lies one of our problem about misinformation. Too many people are just regurgitate opinions of "doctors". Generally speaking, I like to use fallacies for myself, just to be aware about certain pitfalls. Not so much about discrediting others, but rather not fall into one myself. If I realize other people are using fallacies to support their argument, it helps me to build an argument against it. Just don't use it naively: "you're wrong because of fallacy number 42". Using it like this is a bad habit, because of the wast number of fallacies, you can probably kill any discussion.
• faitswulff 6y ago
  I saw an example of a poorly applied logical fallacy here on HN. The poster was claiming that an app’s popularity was meaningless via argumentum ad populum and that their chosen alternative was “correct.” It’s like arguing that everyone should replace their USD with Bitcoin. In an ideal world, perhaps, but we don’t live in an ideal world; we live in a world where popularity matters. I’m sure there are other examples of this kind of logical purism being misapplied to the real world, especially among programmers.
  • hyko 6y ago
    I don’t think those examples are right; argumentum ad populum is about relying on the popularity of a belief to prove whether it’s true or false. What interesting is that in the example of Bitcoin, since currency is little more than a shared belief in something, this would not really constitute a logical fallacy.
    • faitswulff 6y ago
      Regarding your first paragraph: exactly. Regarding your second: you’re making essentially the same mistake. There’s no objective argument here, no deliberations on abstract truth that could be easily countered by pointing out a logical fallacy. Just because it’s a shared belief doesn’t mean it’s not beholden to valid yet purely subjective arguments such as “I don’t have any BTC” or “I don’t have the technical ability to use BTC.” In reality, nobody is going to use your product or service because you can make a fallacy-free argument for it. On the other hand, popularity is a very real and useful indicator of utility. You may hate jQuery, for instance, but it’s going to have a plethora of documentation, blog posts, and StackOverflow answers. Basically - the real world is tolerant and even encouraging of logical fallacies.
      • hyko 6y ago
        Yeah, I guess the real world is tolerant of them – otherwise we wouldn’t call them fallacies :) If we’re to get closer to the truth though, we must be intolerant of them (but not each other). I think it also depends on precisely what statement you’re trying to prove. In the jQuery example you have to get really specific, because just talking about the best can be pretty vague. There are many examples of best where merely pointing to the popularity of jQuery is a logical fallacy, and perhaps some where it isn’t (e.g. the breadth of documentation making development easier). This is really a different class of problem to something more abstract such as the belief in alien civilisations, where the fallacy is more clear cut. The currency example is a slightly different case though, because it’s the belief in the currency itself that creates the currency. So the statement everyone should replace their USD with Bitcoin is undermined by the overwhelming depth and breadth of belief in USD (misplaced or not). So I don’t think it counts as a logical fallacy, because it goes beyond merely trying to leverage the majority opinion on the subject; the beliefs themselves are absolutely instrumental in driving the relative utility of USD and Bitcoin.
• bjt2n3904 6y ago
  This is known as the "logical fallacy fallacy", which rarely shows up on these lists. "orange_tee made an appeal to authority, therefore every conclusion he is attempting to draw is false and can be rejected out of hand." It's a very jejune debate tactic, by people who have just dipped their toes into logic for the first time, and have discovered a brand new way to shut down arguments.
• tpoacher 6y ago
  this is because fallacies deal with deduction, not inference. still useful tools though.
• FabHK 6y ago
  Yes, the "appeal to authority = fallacy" can be employed to shut down legitimate arguments, as well as the "ad hominem = fallacy". There is a great clarification here: "The ad hominem fallacy fallacy" EDIT: debunking -> clarification https://laurencetennant.com/bonds/adhominem.html https://laurencetennant.com/bonds/adhominem.html
  • bena 6y ago
    That doesn't debunk "ad hominem" as a fallacy, it just says that sometimes people accuse others of ad hominem when it doesn't apply.
    • user-the-name 6y ago
      Yes, people think "ad hominem" means "he insulted me so I win". "You are wrong because you are an idiot" is ad hominem. "You are wrong, and also an idiot" is not.
    • FabHK 6y ago
      You’re right, I’ve edited. It’s the abuse of crying “ad hominem” that’s the problem.
  • darkerside 6y ago
    Logical fallacies should be part of a conversation, and shouldn't shut down anything. They are thinking tools, not debate weapons, although they can be used as such.
    • koheripbal 6y ago
      If someone is making an argument with obviously invalid logic, then I think it's reasonable to not continue the conversation if they are unwilling to present a logical argument.
      • darkerside 6y ago
        If you really on logic for everything, people are eventually going to walk away from you. Don't ask me to logically prove that because all I have is the anecdotal evidence of experience. Not every conversation is a scientific debate. If you want to learn, you should still participate in them.
• yters 6y ago
  Fallacious parts of an argument cannot contribute to its soundness. Fallacies either contribute untrue premises or invalid deductions, such as affirming the consequent. This is a matter of fact.
• hooande 6y ago
  You misunderstood the fallacy. it's not "don't listen to experts". it's "a proposition isn't true only because another person says that it is true". While you may chose to save time by deferring to expertise, you can't use that to convince someone else that an idea is correct. Logical fallacies are easy to misunderstand, which makes them very dangerous. That's why this website has examples, I guess. This is a case of knowledge that might require a teacher who can give feedback and guide understanding.
  • koheripbal 6y ago
    Maybe the word "fallacy", is in that case, misleading. The probability that an assertion is true drastically increases if there is a clear consensus among the subject matter experts in that field. This is important when certain assertions cannot be personally verified. For example, I cannot personally verify that Pluto has a moon. ...but I can show people pictures of an object that the experts claim is Pluto's moon, and point to various statements that Pluto has a moon. The probability that Pluto does not have a moon would require a massive conspiracy, or some unimaginable misunderstanding, that the probability is extremely low. Is it still a "fallacy" to point to the statements of those scientists?
    • froh 6y ago
      The point is that some retired professor in microbiology takes a little lamplight making claims about covid, which unfortunately are factually utterly and desperately wrong. Now people refer to him expert in a facebook thread. That's the "appeal to authority" fallacy, which you could call out. Extensive use of fallacies is in the active repertoire of demagogues. That's why it helps to study them, a bit, so you recognize a skunk if you meet it in the wild.
    • packetlost 6y ago
      This is the correct use of the word "fallacy." The "appeal to authority" fallacy is the belief that because some piece of info comes from someone (it's generally an individual) who is in a position of authority means that it's automatically true. It has nothing to really do with whether the piece of info is accurate or not, and consensus is generally a way to mitigate the issues that arise from this fallacy.
• bitshiftfaced 6y ago
  > For example, using "appeal to authority", it is logically true that just because a group of Fields Medalists think your proof is wrong, does not necessarily mean that your proof is wrong. But in practice, there is a very high chance you are in the wrong. The proof is wrong not because the status of those Field Medalists but instead because of the content of their argument. That's all that the appeal to authority is saying. I'd agree that it's a mistake to relate the existence of a logical fallacies to the probability of a statement being correct. Instead, it only gives information about whether the reasoning of the statement is on solid ground.
  • threatofrain 6y ago
    But what kind of reasoning is on solid ground when we’re talking about logic... outside of math? Saying logic here is almost lying to ourselves because we’re not expecting anyone to create logical chains of reasoning. Do mathematicians even use logic as a reasoning tool, as opposed to a proving tool?
    • bitshiftfaced 6y ago
      Isn't that exactly the question that informal logical fallacies seek to address? I don't think you can just throw away the word "logic" like that. We try to make arguments using deduction and inference, so there is a logical structure behind them. It's just that it isn't as well-defined and doesn't have the mathematical rigor of formal logic.
      • threatofrain 6y ago
        Logic a fundamentally different process of intellectual productivity, which is why mathematicians don’t see proving and reasoning as the same thing. Formal methods weren't even widespread until late in mathematical history, yet somehow we had mathematical productivity. Mathematicians can scarcely describe their own thinking process, and proving is often the last step to mathematical reasoning. Talking about logical fallacy in ordinary conversation is backward.
• kybernetikos 6y ago
  Many fallacies are perfectly sensible ways to reason in a messy, imperfect world. ad hominem - someone you know to receive large sums of money from cigarette manufacturers gives you several plausible sounding reasons why cigarettes don't cause cancer. It's an adhominem to doubt his arguments based on your knowledge of how he's getting paid, but it's also sensible. argumentum ad populum - an argument isn't necessarily true just because lots of people believe it, but in the absence of you being able to work out the absolute truth from first principles, it's completely sensible to take into account what other people believe when you evaluate your options, or what people in your situation have typically believed (appeal to tradition) denying the antecedent - red sky in the morning implies shepherds should take warning. It's not true to say that just because there isn't red sky in the morning, then shepherds should assume the weather will be fine, but excluding one of the conditions in which shepherds need to be careful is weak evidence that shepherds will be fine. The old 'absence of evidence is not evidence of absence' one, although I didn't see it on this page. Actually it is. It is weak and incomplete evidence of absence, but in the right circumstances it can be perfectly reasonable to change your opinion on whether something is present or not based on a lack of evidence for it being present. In the real world, weak evidence is often the best we're going to get and we're often going to be in situations where thought shortcuts are necessary and valuable. Pointing out fallacies is usually poor argumentation. My pet peeve on this one is the 'burden of proof'. Normal human debate isn't a game with strict rules and a judge that awards points, and I'm not sure it'd be any better if it were. You engage in a debate with someone when you both want to change the other persons mind. If you didn't want to change their mind you shouldn't be debating with them. You're very unlikely to change their minds by telling them that the burden of proof is on them not you (much more likely to end up arguing about who really has the burden of proof, a fruitless and uninteresting topic).
  • zamadatix 6y ago
    Yeah, nothing about a logical fallacy says it can't be useful just that it's not strict logical proof. As such it's useful to call out that a logical fallacy doesn't equate to/overrule direct evidence or sound logic but that doesn't mean things behind the indirect evidence or unsound logic are inherently 100% useless information in decisions or discussions.