Logical fallacies
yourlogicalfallacyis.com
yourlogicalfallacyis.com
Refer to something written by an expert rather than demonstrating it directly yourself? Appeal to authority.
Suggest that a particular source of information may be unreliaible? Ad hominem
Voice a concern over the direction some policy appears to be taking? Slippery Slope.
Many arguments are also based on statistics rather than directly on logic.
Logical fallacies can be used to expose highly axiomatic thinking though.
An appeal to authority fallacy has to be without reason backing up the appeal other than the fact that they are an authority.
You can suggest that a source of information might be unreliable because of a poor track record in the the domain, or a conflict of interest - that's not ad hominem.
One can speak against the direction of a policy without committing a slippery slope fallacy by not making unsubstantiated claims about what will happen. If you can cite examples of similar policies that have led to effect Y happening with rational explanations for the causes along the way, then that would avoid the fallacy.
I certainly have never measured it, so all I can do is cite sources of information which are assumed to be authorities. I can be relatively confident in my reply by citing multiple sources of information but I'm still ultimately relying on something I can't realistically provide other evidence for.
According to wikipedia the second could possibly fall under "Circumstantial Ad hominem" in that suggesting a source has bias does not necessarily make them incorrect. Though this depends on the nature of the argument.
I think the third is more tricky to pin down because it is going to depend again on the nature of the argument. You may suggest concern about some policy without a concrete example of X leading to Y because it may not have happened before. But again this depends on the nature of the argument.
I think my problem is more with the way in which logical fallacies are abused in internet arguments rather than the fallacies themselves. For example somebody saying "You are wrong to be concerned about policy X because slippery slope fallacy".
2. Agreed that it's contextual. I merely wanted to point out that not all discrediting is ad hominem as you seemed to imply.
3. Also agreed that it's highly dependent on context. Again, just pointing out that one can speak out about policy direction without committing a fallacy.
And yes, I dislike that as well! The fallacy fallacy: https://yourlogicalfallacyis.com/the-fallacy-fallacy
Most people know ca is ~3000 miles from ny. Most also know that the time difference is 3 hours. So 1 time zone is approx 1000 miles. Circumference = 1000 mi x number of time zones.
The "appeal to authority" is only a practical fallacy in a situation where it is feasible to directly evaluate the claim against reality itself.
I'd say that for practical matters, there are degrees to this. Example: Health. There's a difference between referring to a doctor versus a Hollywood celebrity.
Most of the time I see people calling out a "slippery slope fallacy", they're often applying it erroneously. The actual fallacy is in asserting that a step in a particular direction logically entails a further step in that direction; it is fallacious in most situations to assert the slippery slope as a deterministic necessity.
But that has no bearing on whether or not the slippery slope actually exists; just because it isn't logically entailed doesn't mean that, in the empirical context of the matter, a step in one direction doesn't actually make a further step in that direction more likely.
There is an empirical slippery-slope phenomenon in political debate, related to the concept of the "Overton Window" [1], and it exists contingently irrespective of whether or not it's logically necesssary.
http://www.amazon.com/Thank-You-Arguing-Aristotle-Persuasion...
There are two main reasons that fallacies are bad. The first is that they're not rigorous, which is why parent mentions pure mathematics. Perfect logic matters, sometimes. Strong philosophical positions are like this, too: the kind that takes you years to develop and stabilize. But it's actually pretty rare for anyone to spend much time here.
The second is that fallacies are meant to contort the mind. Which isn't a bad thing, but if you're not equally equipped in logic and an understanding of fallacies yourself, deft usage of fallacy will run circles around you. While virtually all thought experiments are fallacious by nature, if you can't figure out where the boundary between allegory and reality are, you're going to have a problem.
The philosopher Arthur Schopenhauer documented these tactics humorously in The Art of Controversy (Chapter III):
http://ebooks.adelaide.edu.au/s/schopenhauer/arthur/controve...
"The fallacy fallacy: You presumed that because a claim has been poorly argued, or a fallacy has been made, that the claim itself must be wrong."
There's also a lot of useful metadata that gets communicated via "fallacious" argumentation: the intentions and credibility of the speaker, alignment of incentives, presence of alterior motives, etc. This is all entirely appropriate, especially - as in politics - when the debate is about an ought rather than an is.
Logical Fallacies was one of my favourite elements. (Deductive logic is fabulous as well, but of limited application in a real world of probabilities.) If I could wave my magic wand and change education, logic would be right up there with entrepreneurial economics as a mandatory class to support kids understanding how the world works (and how it can work in their favour).
Well, it's an argument that's often bad. Slippery slopes can actually happen in the real world. But I suppose anyone making a slippery slope argument has the burden of showing that the slipping is likely to occur.
If someone is saying "A will cause Z OMG!" without a strong causal chain, the fallacy you want is probably "non sequitur", or you point out what other thing is wrong with their reasoning. But you don't just assume the argument is invalid, as you do with formal fallacies, because slippery slopes are indeed real.
At the risk of going too meta, someday am I going to have to deal with some idiot who thinks "slippery slope" is a formal fallacy, because they were all lumped together like this? If the site gets enough traffic, it will get some people who can't tell the difference, who will come away with the wrong impression. Not that many, but the possibility is, IMO, an indicator that lumping them together like this is a bad idea.
It already happens elsewhere. You can observe an ongoing trend and justify the expectation that it will continue using the motivations and past behavior of the actors involved, and someone will still say, "Slippery slope, I win!"
yourlogicalfallacy.is/ad-hominem
An argument strongly compromised by fallacies, made by someone otherwise intelligent, suggests to me disingenuity and intellectual dishonesty - and it affects how willing I am willing to engage in debate in return.
http://marginalrevolution.com/marginalrevolution/2011/03/the...
Rhetorical training was a paying job back in the days when public speaking was a major source of entertainment. It's a pity it is not more widely taught, for self-defense purposes.
When arguing with others it is best to employ the principle of charity, even to the point of improving the other party's arguments to make them as strong as possible, and then pointing out where you think they are wrong.
It is best to study fallacies in order to avoid making them, rather than throwing them at others in the manner of the proverbial religious hypocrite who 'read ye good booke in order to rake all the blessings unto himself, and to shovel all the curses unto his neighbours'.
https://news.ycombinator.com/item?id=5391677
(edit: which is why, even if the parent is somewhat tongue in cheek, I'm complaining about it, heh.)
The problem is that fallacies are not always fallacious. In fact, I'd guess that the majority of online arguments which people label with names of fallacies are not completely invalid, though they may be less valid than other arguments.
The fallacy in calling something a fallacy, so to speak, is that while an argument that includes a fallacy cannot rigorously prove that something is true, your typical discussion where fallacies are brought up is not an attempt to rigorously prove something, and cannot be, because it's about an inherently subjective statement or one which not enough information is available to prove or disprove. To advance the discussion in that case, an argument need only demonstrate that the statement is somewhat likely to be true - from a Bayesian perspective, that a rational actor should assign a higher probability to the statement being true than if he did not consider the argument - and many "fallacious" arguments satisfy this criterion.
For example, a slippery slope argument is best substantiated by justifying why doing X is actually likely to lead to doing Y, but even without substantiation, pointing out that Y is a possible outcome logically makes X a slightly worse idea to consider, and there is a lot of room in between for partially but not fully substantiable arguments. Or to pick a random example from the site, an appeal to nature is fallacious because "because something is 'natural' it is therefore valid" is not necessarily true, but while it's easy to put excessive credence in the correlation between "natural" and "good", that doesn't mean there is no correlation: in the absence of stronger evidence to the contrary, "it's good because it's natural" is a valid starting point. Even the mainstay of fallacies, ad hominem, is subject to this: because arguing about subjective points necessarily involves taking a bunch of factors and assigning them essentially arbitrary weights (theoretically based on one's experience of what factors have proved accurate in the past, but still arbitrary), it's perfectly valid to argue that because someone has demonstrated bad judgement in the past (especially about a similar judgement call, as in the post I cited), their assignment of weights in this case is more likely to be incorrect.
A response of "this is fallacy X" is itself quite valid as a heuristic argument - an argument containing a fallacy is less likely to be valid than an argument not containing a fallacy - but it's not sufficient to completely dismiss most arguments, and those who would use the rhetoric of logical fallacies to purport to do so, linking to a well-designed web page that says "your argument is invalid", are essentially committing the fallacy of arguing from authority. While certainly not all arguments deserve well-reasoned responses, just claiming that an argument is a fallacy is generally not a well-reasoned response, and in practice it tends to be rude and unproductive. Linking to a description of a logical fallacy carries a certain implication of "your argument is so bad that you need to be educated about the basics of fallacies". It's like saying RTFM - reasonable in response to a poorly formed or low-effort question, but rude in response to a high-quality one.
I really enjoyed the book, fun read.