Frequently when someone talks about a slippery slope, someone else will argue that this person is using the “slippery slope” fallacy. As this article convincingly demonstrates, the slippery slope can be real. Some actions make later more extreme actions far easier and more likely because the first action changes the political, psychological, or economic incentives to take the latter action. The argument can be misused or false, but that doesn’t make it a fallacy. Agreed?
Not agreed. Of course the slippery slope can be correct. “Poisoning the well”, “Strawman” and “Ad Hominem” and any other fallacy may be correct as well.
True Strawman in particular I fall prey to, in that I try to predict my opponent’s next argument and argue against that as well, rather than waiting for him to make it. This leaves me open to the “Strawman!” accusation and scores him a “point,” and also saves him the move, if you know what I mean. If I just keep my mouth shut, he’ll make the point and then I can refute it, and it’s not a Strawman and I win the point, you see. My private “Strawman” was in fact correct. But I’m impatient sometimes.
All fallacies COULD be correct at some time - that’s why they sound convincing. Much like stereotypes, if they didn’t have some eensey-weensey kernel of truth, they wouldn’t have gotten started. But the fact that they’re not always true makes them stereotypes (Some black people DO like watermelon, but that doesn’t make the stereotype true.) The fact that is doesn’t HAVE to be true, or isn’t always true is what makes it a fallacy.
I had trouble loading the article but I agree that it can be real. I am not a smoker but I have watched how smoker’s rights have gotten incredibly squeezed over the years in ways that were promised to never be an issue. Smoking sections in restaurants became no smoking in the whole restaurants to smoking bans in bars. It goes on and on. When these things were barely started some were screaming “They are going to ban smoking” and were made to sound like fools. It turns out, there are people that intend to ban smoking or something very close to it and they are doing an admirable job. The small footholds started the slippery slope.
This phenomenon is why the NRA is so powerful and often looks like a bunch of loons on what they oppose. Many years ago, I read some article in their magazines about how control control activists were using slippery slope techniques to enact almost complete bans over time. National registration databases would eventually be used to identify existing gun owners when bans for one type of gun and then another were put into place. Gun control activists have shown the tendency to use the slippery slope to their advantage so this seems like a reasonable fear.
I think you could find lots of real slippery slope examples in cases where there is widespread banning of any popular thing or where the government wants to impose widespread control over time. This is why some people oppose national id cards and other innocent sounding things but they may be right.
I don’t think that’s quite right; that would mean that all statements of probability or inference are fallacious. In your strawman example, if you accurately predict your opponent’s argument, it simply isn’t a strawman. A strawman, by definition, is an argument that your opponent is not making. I think similar points can be made about ad hominem, etc.
Well ad hominem attacks in particular can be true but still a fallacy. An ad hominem attack, by definition, is a personal insult designed to discredit the speaker. Even if the accusation is true, however, that fact has no point on the debate whatsoever if the point is still valid. Note that something like “he’s lying, he said this but the truth is…” Is not “ad hominem” since it’s proscribing the action to a particular debate point, which is then refuted, but “he is a liar, so his point can’t be valid” is ad hominem because it proscribes a general idea to the person without providing any reason to believe that particular debate point is invalid.
Slippery Slope is a fallacy also. For example, the reasoning that allowing Harry Potter to be read in schools will encourage more children to take an interest in real-life witchcraft and the occult, which will lead to the degredation of the morals of society, is a slippery slope. I think the key difference between a slippery slope argument and an acceptable logical connection is
A) a slippery slope argument tends to make the argument unavoidable (ie. if this happens, it WILL lead to nuclear war)
B) the scope and number of connections a slippery slope makes tend to be greater (doing A, leads to worse B, which leads to incredibly bad C, which leads to catastropic, which leads to APOCALYPTIC D), or now that I think about it, sometimes the reverse with undefended and/or omitted middle points (if you go driving today, you’ll die!)
C) a valid logical series provides evidence, defended logic, and doesn’t assume a catastrophic finale like a slippery slope, which is designed to play at people’s emotions (especially fear) without attempting to make a valid defense for the slippery slope (the usual defense for it being, if you don’t believe me you’ll die!)
You are confusing formal fallacies with informal fallacies.
Formal fallacies are errors in deduction, and are always false. For example, suppose you make the statement “If P then Q”, then show that P is false. Many will then assume that Q is false, but this is an error of logic.
Informal fallacies are those which fail to adequately explain cause or relevance to the matter at hand. “Adequately” is the key word here, as the adequacy of an argument must be evaluated in context.
A slippery-slope argument (or any informal fallacy) by itself is never good enough to prove a point. But tying it to similar-enough examples, or finding solidly-provable reasons to support the analogy will strengthen such an argument to the point that you can’t reasonably claim the slippery-slope structure of the argument makes it fallacious.
Logical fallacies, on the other hand, can never be strengthened by attendant circumstances; the central flaw in the logic is lethal.
But I think that this form of slippery slope argument is almost never made. When people invoke the slippery slope, they are almost never saying that some action will logically require another. They are just saying that the probability of the latter action is significantly increased.
I guess what I meant to say is, to the extent that there is such thing as a slippery slope fallacy, almost no one uses it that way. Most of the time when some says “that’s a fallacy!” they mean they disagree with this particular slippery slope argument.
I have to agree with Richard Parker on this. A strawman argument, by definition, is a misrepresentation of a person’s argument. Preempting a person’s argument because it is actually predictable, has already been refuted elsewhere, or for some other similar reason is a perfectly legitimate form of debate.
In a case like this, the person making the accusation may actually be guilty of the strawman fallacy. 
Edit: (Sorry for the tangent…)
LilShieste
I don’t know where you got that I didn’t get this distinction.
You seem to suggest however that there is something about the structure of a slippery slope argument that makes it an informal fallacy. What is it?
(bolding mine)
Agreed. But I would change the title of your thread to allow for both possibilities. A slippery slope argument can, and often is, fallacious.
An argument that is simply wrong in a particular instance is not a fallacy.
You’re conflating the truth of an claim with the structure of the argument extended to support it. A claim can be true–and empirically verifiable–even though an argument in support of it can be fallacious, i.e. lacking in complete logical structure or making unsupported assumptions. When you make a claim like, “Allowing children to eat sweets between meals is a slippery slope that leads to obesity-related health probems in adulthood,” the claim can certainly be valid (i.e. adopting a habit of thoughlessly consuming simple carbohydrates can lead to eating patterns which encourage excess consumption and interference with the normal blood sugar regulation mechanisms) but shortcuts its way around the construction of a logical or falsifiable rationale.
Stranger
this is, based on the definition, actually false. in particular, from wikipedia:
The slippery slope can be valid or fallacious. The name “fallacy” (and it is in “informal” fallacy, check the wikipedia article for “informal fallacy” as well) is given to it since it’s used so often, and it’s such an identifiable argument tactic that it deserves its own name.
I sort of accidentally buried one of my points in part C. In particular, the second part, where I pointed out that a fallacious slippery slope is often constructed to play at people’s emotions or abuse people’s lack of knowledge about a subject, drawing bizarre conclusions that the average person can’t disprove (or indeed, using unprovable assertions), leading them to believe that it’s a necessary outcome.
I agree that there is such a thing as a valid slippery slope, and I don’t think anybody will disagree with that, but it can’t generally lose it’s status as a fallacy. My broken clock isn’t broken! It’s right twice a day!
I agree. But that’s not what I’m saying. The argument is fallacious when the logic behind it is flawed. Sometimes a slippery slope argument is valid, other times it is fallacious (based on faulty logic).
Slippery slope is indeed exactly like the wedge in the door, or the loophole that become a window that becomes a breach.
The difference between a slippery slope fallacy and a slippery slope argument is that a slippery slope argument backs up the claim that one thing will lead to another. I recently called out a claim roughly like the following as a fallacious slippery slope argument:
‘It’s a slippery slope; if we legalize marijuana then worse drugs like cocaine will be legalized too.’
(Yes, they actually used the term ‘slippery slope’ in their statement.)
The problem with this, of course, is that there’s no reason for me to believe that it’s true, and nothing is provided to even try and convince me that it’s true. I know of no inherent connection between the legal states of cocaine and marijuana, any more than I see a connection between the legal states of tobacco and marijuana. Such a link might exist, but it’s not provided in the argument. The arguer has left it as an excersize to the reader to get all scared of the horrible outcome and concede forthwith.
Had supporting evidence for the connection between the ‘levels of slope’ been provided, this would not have been a fallacious arguement. Absent it, though, it is one.
If we declare the slippery slope no longer a fallacy, the very foundations of logic itself will be shattered and philosophical inquiry will be set back by centuries.
I didn’t mean to say that all slippery-slope arguments are fallacious; quite the opposite in fact.
On preview it appears that begbert2 expalins this. “Slippery slope” is an informal fallacy because it is often assumed to be sufficient in and of itself to support a point. It is not, but can be part of a larger argument, in which case the arguer cannot be fairly accused of falling for the “fallacy of the slippery slope”.
The same thing can be said for “Post hoc ergo propter hoc”; just because an event happens after another event doesn’t mean they are causally related. Anyone who asserts a causal relationship between two events based solely on their position in time is guilty of this fallacy. However, noting the consecutive timing *as part of a general argument to show causality * does not in and of itself make the argument fallacious.
It’s shorthand for a more complicated argument. You think that alone makes it a fallacy?
So, if we define informal fallacy as any pattern of reasoning which is false due to the falsity of one of it’s premises (as many of you seem to be doing in pointing to the wikipedia link that it defines it that way), doesn’t its status as a fallacy become dependent on the content of the premises? I find that to be an odd usage of the word fallacy, which generally refers to the structure of an argument.