158

Because they expect arguments, not inflammatory noise No, I am calling them an idiot because that's ... just my bloody opinion. Exactly that: just your opinion. An opinion is not an argument; it is not a syllogism, it is not reasoning, it is not fact, it is not evidence, it is not anything other than just that: your [expletive] opinion. So why do ...


140

It may very well be a poor argument, but it's not a logical fallacy People are too quick to jump on the "fallacy" bandwagon. There is no logical fallacy occurring here. It may very well be an argument that is not particularly convincing (In fact, I wouldn't use the argument), but there is nothing logically fallacious about it. If a person asks "If you ...


126

It is the False Dilemma or Bifurcation Fallacy. If you don't like it, then move. Let's say you have caused some problems by questioning the decisions, speech, and actions of someone who is actively seeking social, economic, and/or political power. And you're confident that you have every right -- or even duty -- to do so. Those in power who are profiting ...


76

If an opinion isn't intended as an argument, it is noise Frankly, nobody wants to hear your opinion unless you have some point to make about it. You can have the opinion that a person is an idiot, but if you're putting in the effort to type it in then you obviously have some point to it. I don't state every opinion I have on every post I make on the ...


72

Circular reasoning doesn't "discredit" any point of view --if anything, it demonstrates internal consistency. However, it also doesn't provide any external support for a point of view. It has no legitimate force against anyone not already convinced of the conclusion. This is a structural issue entirely independent of the question of whether we're ...


53

Geoffrey refers to feedback loops as a valid example of circular reasoning. This is not correct: they can be valid but they are not circular. Instead they are an example of reasoning by induction. It is not a implies b and b implies a. Instead it is an implies bn and bn implies an+1. That is valid so long as you can start it off with a0. For example, it is ...


51

There is no argument, therefore there can be no fallacy There is no fallacy here, no logical error in argument as e.g. in affirming the consequent. This is so because there is no argument here at all - only an expression of viewpoint. Fallacy presupposes argument. No argument, no fallacy : the concepts are tied.


50

A fallacy in an argument requires that there be an argument at all. What you're describing: Then someone counters, "What do you mean by 'bites'? Define 'biting people'. Define 'dog'." is not even an argument. There is no fallacy there, because it doesn't even make a claim. What it does – in the example you present – is bog down the discussion with ...


48

Marx, socialism and communism Neither Marx nor Engels provided a blueprint for the socialist state. There could in their view be no such thing as a communist state since under communism, with no class-rule or management needed, there would be no state because no classes. Even the Soviet Union described and understood itself as socialist, not communist : ...


44

There are multiple good answers here, including references to modus tollens and the contrapositive (both of which are correct). What helps me understand this concept is a more intuitive/layman's perspective. Say that if it's raining, you ALWAYS bring an umbrella outside. (Assume that you have a perfect memory). Therefore we have: Raining -> Umbrella ...


34

This is not a fallacy, just the old problem of induction. A case of hasty generalisation would be to conclude that the witness tends to lie, if you have observed it two times in a row.


33

When you say "the phenomenon of cats being born into this world is natural," what that means is, "the phenomenon of cats being born into this world is part of the set of natural phenomena." In other words, "is" here indicates belonging to a particular set, as it often does when there is only a predicate adjective. There is more than one element in this set (...


32

All informal fallacies take their force from their similarity to strong arguments. In this case, if you say "This boy lied 19 days in a row, therefore we have good reason to disbelieve him on Day 20," that is a perfectly good argument (assuming it isn't suppressing other relevant information). But if you say "This boy lied 19 days in a row, therefore what ...


31

Generally speaking, in philosophical discussions, it is often required to provide definitions for words that seem obvious otherwise, let me give you an example: When you say : The King of France is bold . Russell may ask you, what do you mean by The? (I will not talk about the theory of descriptions here). And Russell's question here would be legitimate, ...


29

Here is the argument: No N is not-N. No not-N is N. All C are N. No R are C. Thus: No R are N. The syllogism is invalid for two reasons. First, the third premise denies the antecedent (cats) of the fourth. There can be other animals that are normal. Wikipedia: Denying the antecedent; Formal fallacy. Second, a term that is distributed in the conclusion (...


28

This fallacy is generally called argument from incredulity, or argument from failure of imagination. https://rationalwiki.org/wiki/Argument_from_incredulity It also is a subset of the argument from ignorance. Informal fallacies often overlap, and bleed into each other. This fallacy is a common one,even among respected philosophers, as it is a ...


23

The second premise is false unless "heinous crime" and "insane" are defined to make it true by definition, in which case the definitions are question begging. But because people committing heinous crimes are convicted despite the insanity defense, premise 2 fails at least on the legal definition of "insanity". The third premise is also false; otherwise ...


23

Basically, my question is, why do people assume that any insult is an ad-hominem fallacy, when, according to the definition, only certain insults are ad-hominem fallacies. The simplest answer here is that people do not all assume that any insult is an instance of an ad-hominem fallacy, and those that do are sometimes mistaken. Firstly, an ad-hominem fallacy ...


22

In any communication, there is a context in which that communication is occurring. If they believe they are in a context of debate, and that your statement is intended to be part of the debate, then they are justified in declaring your statement to be an ad-hominem within that context. If you believe you are not engaging in a debate, and are instead merely ...


20

This seems like a false dilemma: major premise: "either X is good and Y is bad, or X is bad and Y is good". minor premise: "Y is bad". conclusion: "X is good". Because the major premise is fallacious, the syllogism (though perfectly valid) is not sound. In your examples it's elaborated slightly: the interlocutors both seem to agree, on some level, that ...


20

I think I found something that comes close: Appeal to probability (Wikipedia) An appeal to probability (or appeal to possibility) is the logical fallacy of taking something for granted because it would probably be the case (or might possibly be the case). and An appeal to probability argues that, because something probably will happen, it is ...


19

The OP presents a situation wondering if a logical fallacy has been committed. The following claim is made: Fossil fuel consumption due to mobile phone usage is similar to that of private transportation, so if you think we should switch to electric/bike to fight climate change, then you should also stop using your mobile. The claim is denied without ...


18

A criticized exception to the rule that falls short of the rule makes for valid negation of criticism OK, that headline requires changing direction of the train of thought at least three times, so let me clarify: The statement "That is not a true Scotsman" is not necessarily a fallacy In order for "No True Scotsman fallacy!" to be a valid objection to an ...


18

Fallacy of division : A fallacy of division occurs when one reasons logically that something true for the whole must also be true of all or some of its parts. The assumption of the fallacious argument is that "the fossil fuel consumption of all communication networks, including the Internet, is estimated to be about half of the fossil fuel consumption ...


17

I think the fallacy is something along the lines of: Because we cannot provably apply rational thought to what motivates every insane person, every time, we can never apply rational thought to the insane in any situation. It also presumes that an explanation one's actions has to be necessary and sufficient, rather than merely a way to convey information. ...


17

If this logical fallacy is used as a retaliative defense, it is called tu quoque ("you too"). You, who accuse me, do worse things than me; thus I am not bad. This doesn't cover all the instances, but it came to mind upon seeing Trump and Clinton in the question.


17

Logicians distinguish two kinds of bad arguments, unsound and invalid, see IEP's Validity and Soundness. A fallacy is a flaw in logic that makes an argument invalid. Unsound arguments, on the other hand, may well be logically valid, but argue from false premises. The problem pointed out in the OP, that the world referred to by the arguers is unrealistic, ...


17

Finding a logical fallacy in someone's argument does not permit one to conclude that that person's conclusion is false only that the argument is fallacious. If one uses a logical fallacy in someone's argument to claim that the conclusion of that person's fallacious argument is false then that would itself be a fallacy known as fallacy fallacy or argument ...


17

"No True Scotsman" is one of those categories of fallacies that is rather subjective. If Person A says that X is not Y because it lacks Z, and Person B says that this is a No True Scotsman fallacy, then it comes down to whether Z is a valid requirement for Y. In the case of communism, claiming that the USSR didn't live up to Marx's ideal is a reasonable ...


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