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Kettle Logic (wikipedia.org)
139 points by secondary on March 10, 2022 | hide | past | favorite | 80 comments


There is a joke I love that illustrates the concept:

"Ladies and gentlemen of the jury, my client was nowhere near the scene of the murder, he didn't mean to pull the trigger, and that son-of-a-bitch had it coming!"


There's an old Russian joke about it as well, roughly "That was a long time ago and didn't happen anyway."


And the corollary: "Even if it didn't happen, it's still horrible!"


And there's the notorious "That’s Not Happening and It’s Good That It Is".

I think the honest version of this kind of argument is helpful in some cases though. Not everybody agrees on the same set of the facts, and sometimes the conclusion one is arguing for is true regardless.


These kinds of jokes are often used to make mock lawyers and even the legal profession.

But under US criminal the defense doesn’t have to do anything, the entire burden is on the government to prove beyond a reasonable doubt that: 1) a criminal act happened, 2) the defendant committed the act and 3) defendant had intent to commit the crime.

Naturally opening/closing arguments actually sound very much like your joke…the government can’t prove a crime happened; if they can they can’t prove my client committed the act; and if they can they can’t prove my client intended to commit the act.

It sounds funny, but logically it makes a lot of sense to say things like we don’t need to a get to the question of if the defendant committed the crime because the government can’t prove beyond a reasonable doubt a crime was committed (e.g. no body in a murder case).


What would that be in programmer speak?

The intern had no write access to the production database, he didn't mean to do the commit, and our network engineers had it coming?


The program didn't have write access to the log file, it didn't write to the log file, and who cares if there's a bit of junk at the end of the log files anyways?

https://dirtypipe.cm4all.com/


I can't reproduce it; you're using it wrong; it's a feature, not a bug.


"Ladies and gentlemen of the management, I was nowhere near the git repo on the day in question, I didn't mean to make that commit, and the customers suck anyways so they deserved that data loss bug."


The line must be useful for something; you can't prove it actually does anything; who cares, you can always just restart the server!

(...when presented with a line in the script that randomly hangs the server.)


    void *p = NULL;
    int i = *p / 0;


Shouldn't kettle logic be considered a paradox of Logic? Those options are mutually exclusive only if there are no hidden variables. We could make them theories and assign probabilities:

There is X probability the client was nowhere near the scene of the murder, and Y probability he didn't mean to pull the trigger

That way these are not exclusive and the contradiction disappears. Now suppose the client is convicted because X is too high, years later a hidden variable is revealed that reduces the probability to zero. He is released from jail, but another hidden variable appears that increases Y to 100%.

There should also be a probability for unknown unknowns, when a fair coin falls sideways.


The funny thing is, if you spend too much time arguing with anonymous people on the Internet, you will routinely run into arguments that are both invalid and have false premises.


See also: "It Was A Long Time Ago And It Never Happened Anyway"

https://yalebooks.yale.edu/book/9780300192377/it-was-long-ti...


These three can in fact be all true at once, so the arguments are consistent, unlike kettle logic.

"Didn't mean to pull the trigger" does not imply the defendant could pull the trigger.


The three incompatible scenarios are:

  1. The accused was nowhere near the scene of the murder
  2. The accused was at the scene of the murder, and in fact committed the murder, but on accident
  3. The accused committed the murder on purpose, because the victim had it coming.


I got the joke. But it is arguable whether the wording implies "the accused was at the scene of the murder" or "the accused committed the murder on purpose".


it is actually illustrates QM superposition. Also reminds a situation when you're troubleshooting some complicated issue while not having yet enough information - you kind of running several, frequently mutually incompatible, scenarios in your head at the same time.


Classic, been a while since id read that one :)


It seems that this is a sort of "dual" to what's called "Argument in the alternative" [1], which I've seen confused for kettle logic more often than I've seen kettle logic used itself.

It's a subtle distinction. Argument in the alternative considers multiple different possibilities as hypotheticals in order to rule them all out, but isn't that kind of what kettle logic does as well? Can a kettle logic argument be easily rephrased into an argument in the alternative?

I feel like there's a difference between them that's more than just whether the argument is true/valid or not, but I can't quite put it into words.

[1] https://en.wikipedia.org/wiki/Argument_in_the_alternative


The "even if" bit from your link is helpful to consider.

Kettle logic:

1. I wasn't there.

2. I was there but had no motive.

3. I was there, had motive, but had no means.

Argument in the alternative:

1. I wasn't there.

2. Even if I was there, I had no motive.

3. Even if I was there and had motive, I had no means.

The first makes three conflicting statements. The second makes 3 consecutive arguments: I have an alibi, but if you don't believe my alibi, I still had no motive, and if you don't believe my alibi and that I lacked motive, I had no means.


I think it's even better if the burden of proof is placed on the prosecution (as it should be):

1. The prosecution must prove I returned the kettle in a damaged state (they can't).

2. They must prove I received the kettle in an undamaged state (they can't).

3. They must prove I received the kettle at all (they can't).


I think the difference is that in Kettle Logic the presenter knows the truth, and the truth doesn't match any of the inconsistent affirmatives ... or else it mostly matches one of them but the presenter believes it's easier for the audience to swallow one of the other, false, alternatives.


Perhaps, but this also implies that the presenter isn't just full of shit (or biased!). Sad fact is, people have attached truth to subjectivity in society as of late, and so one persons truth may not be another's even though both are wrong. Or right. Or a mix of both.

A good example of this is those rarer occasions when someone is accused of rape that never happened; and social media gets wind of it. To everyone who hears of it, mostly at least; the accuser is the honest one. And in some rare occasions, we find out they were not.

I know this specific examples happens, because it was how my mother was born.


The difference is that the kettle argument is simultaneous making multiple claims which are mutually inconsistent, and thus a kettle argument is by definition invalid. Even if it's true that any one of the kettle subarguments being true would achieve the desired goal of the overall argument (e.g. exonerating the accused person), the fact that all subarguments are being claimed simultaneously means that at the bare minimum we know the person is lying.

Of course, the "argument in the alternative" is only different by a slight technicality: you just put an "and even if I were lying in the previous step, ..." between each subargument.


Seems as though Argument in the alternative focusses on eliminating possible explanations. Kettle Logic involves claiming 2 or more explanations to be true while being incompatible with each other, making it a logical fallacy.


So this is the strategy the UK government has been using for the last few years.


Sadly not just the uk, but yes the blind adoration of the "unrefutable glory of report9" is somewhat sickening...


Sounds very Russian too !


Not coincidentally.


Or, as my generation learned it from Bart Simpson, "I didn't do it, nobody saw me do it, you can't prove anything!"


Those claims are all in principle consistent with each other?


Yeah, I am confused as well. Those three claims are logically consistent. They may be in poor taste but they don't fit kettle logic as far as I understand.


This line is actually used in one of the linked articles[1], "Argument in the alternative", which apparently does not constitute kettle logic.

[1] https://en.wikipedia.org/wiki/Argument_in_the_alternative


I saw that on wikipedia, but I disagree. I think the way that he says each part of his statement implies that the previous part is wrong. So the parts are inconsistent with each other from his comedic perspective:

- I didn't do it.

- (I did it, but) nobody saw me do it.

- (You saw me do it, but) you can't prove anything.

The statements alone, not considering the perspective of the speaker in parentheses, don't strictly contradict each other, but the speaker contradicts himself. He's Bart Simpson; he definitely did it and he would definitely lie about it.


"Nobody saw me do it" and "I didn't do it" aren't mutually exclusive. In fact, if I don't do something, then by definition nobody saw me do it.


In my opinion it's clear that the implied interpretation of "Nobody saw me do it" is "When I did it, there was no one there to see it."


Alice: "Nobody saw me swimming in the pool last night"

Bob: "Oh, how was it?"

Alice: "How was what?"

Bob: "Your late-night swim?"

Alice: "I haven't been swimming in ages."

Bob: "..."


Eve: "Ugh those two are idiots."


Bart’s would be, “It didn’t happen, it was someone else, it was a good thing I did it”.


"I didn't do it, nobody saw me do it anyway, and he can't prove he saw it." There, that's the interpretation that proves it works.


Similar to the narcissist's prayer:

That didn't happen. And if it did, it wasn't that bad. And if it was, that's not a big deal. And if it is, that's not my fault. And if it was, I didn't mean it. And if I did, you deserved it.


Thanks, I hate it.

This is just a quick reminder to everyone to check yourself and make sure you aren't falling into the trap of thinking like this, I know it happens to me occasionally.

And there's very little I've seen that damages relationships[0] more.

[0] All kinds, not just romantic.


Yes, a lot of us do this. My wife keeps telling me to read "mistake were made, but not by me", she says it's paradigm shifting, and helpful to allow you to spot this behaviour early.


Which seems entirely too familiar for some reason...something that came up a lot for four years but then stopped about two years ago?

¯\_(ツ)_/¯


That seems more like "argument in the alternative" (see the comment by a_shovel).


Yep, sounds like Dad.


The dream logic bit is interesting personally, as someone who wakes up if a dream doesn't make sense. As in, there usually comes a point in my dream near a crisis/climax when it dawn's one me that the situation doesn't makes sense and then I wake up. This happens about 2-3 times a week.

For example, 2 days ago I had a dream where I was had to go back to highschool for a year to get a highschool diploma because some technicality or lost paperwork college. Then I find out there was a Spanish requirement that I was scheduled for but was never informed of and that there was a midterm the next day I couldn't fail. Then I'm like okay can I get an exception from the college so I can keep my job? And if I loose this job, how bad is it really? I've already got 3 years at Google, so surely... Wait what? Wake up.


My father-in-law argues against climate change with both "we can't trust natural/historical temperature records" and "the earth has seen far more significant climate change than we're experiencing now".


Obviously this “logic” is bad in the examples. But the brain is continually weighing contradictory branches of subjectivity. If multiple contradictory paths all arrive at the same conclusion, it’s rational to weigh that as evidence in some Bayesian way.


Is such a battery of arguments permissible in legal contexts, e.g. in a criminal defense?


https://en.wikipedia.org/wiki/Alternative_pleading

Using multiple logically inconsistent defenses is generally allowed in the US.


When you think about it, it'd really suck to be failing to prove what is in fact your complete innocence and not be able to advance other defenses that could at least get you a reduced sentence (or even acquitted—correct outcome, wrong reason).


The wikipedia article lists "My dog was tied up and I don't own a dog", which is on the face of it contradictory - But there can easily be legal nuance. For example, if I'm acting as a foster home or running a kennel, I can simultaneously advance evidence that "My dog" was tied up, while also advocating for lack of liability because "It's not my dog".

On the other hand, I've seen a ton of "I didn't do x, and even if I did do X it was acceptable because Y" where Y was the worse crime... that somehow still succeeded as a defense. Thankfully not in a court of law, but public opinion is weird.


'permissible' isn't quite the point ... if it makes the jury think you're lying, maybe it isn't the best strategy.


1. The jury should not base their decision on their belief whether either side is lying.

2. The defence is expected to lie, and if the prosecution cannot prove that every single one of the defence's arguments are lies, then the jury cannot convict beyond reasonable doubt.

3. The jury should assume that the prosecution is lying by default, and acquit if the prosecution does not convince them otherwise.


> 2. The defence is expected to lie

The defence is expressly prohibited from lying. Lawyers have a so called duty of candor [1] outlining this. Defendants testify under oath to make this clear to them. Defence attorneys must disclose to the court if their client lies to the court (and they can't convince their client to voluntarily disclose it instead) [2].

That doesn't mean people are expected to take defendants at their word during trial, juries are allowed to decide they think that someone was lying, but they aren't expected to lie.

[1] https://definitions.uslegal.com/d/duty-of-candor/

[2] https://www.eiglarshlaw.com/when-clients-liewhat-must-you-do...


The jury can decide that any given testimony is a lie and weight it accordingly.


Defense theories are not testimony and, ideally, should not be considered in the evaluation of testimony.

(In practice, humans don't consistently compartmentalize well enough to reliably avoid this, though.)


"defense theories" are going to have evidence associated with them. At that point my point applies.


Certainly, but is there some other penalty for what might be construed as contemptuous and disreputable behavior?


It might be perjury


My dad ran into something similar while on a Jury. It was for indecent exposure

Both sides agreed that the man was in the car with his pants down (defense claimed defendant was looking for a tick on his leg). The defense argued that with the window tinting on the car window, it was not possible to see into the car.

My dad's takeaway from this was that one of these must be true:

1. Someone coincidentally accused someone of having their pants down without being able to see them, and happened to be right

2. The window was rolled down

3. The defense is presenting false evidence


It was literally Kim Potter's defense. Shooting was an accident and untentional, but she was within her rights to use deadly force.


These two assertions ('shooting was an accident...' and 'she was within her rights...') are not inherently contradictory, though. That's what's remarkable about Kettle Logic: genuine contradictions can be employed in a proof in a convincing (and not necessarily invalid) manner. The above can be orthogonal or complementary assertions, but they are not contradictory.


Those aren't actually contradictory, but independent.


That's not kettle logic, that's a mode of legal argumentation that deals with boolean "and" constructions of a law.

If some charge requires both [A] and [B] for the accused to be guilty, then this argument is that it's neither [A] nor [B], but the defendant is innocent if they can prove either half of the argument, since the condition is "[A] and [B]", not "[A] or [B]".


That brings up a question. If someone were within their rights to use deadly force, would they only be acquitted if they used it intentionally?


Whether they were within their rights would only come into play if they had the requisite mental state (intent, recklessness, etc., as for the crime charged) in the first place.


Interesting. That means that in some cases you have to argue that you killed someone intentionally to avoid being convicted.


> That means that in some cases you have to argue that you killed someone intentionally to avoid being convicted

No, you don't.

It's just if you are charged with an offense that requires intent, the question of self-defense (or any other excuse) is moot if the prosecutor can't prove intent beyond a reasonable doubt in the first place.

If you are charged with an offense that doesn't require intent, like involuntary manslaughter, you don't have to argue intent to kill to use self-defense as an excuse.

And even of you are charged with an intent crime, you don't need to grant intent to argue self-defense.


It's only inconsistent if you use "and" rather than "or."


In Polish we have this short and sweet phrase "dawno i nieprawda" - "a long time ago and not true". In my experience, obligatorily uttered when a friend is sharing an embarassing story about you.


It's fitting that Freud's the one to describe this (and unironically tout its benefit? I can't tell.) as there's plenty of his own work that can be suchly described.


This is not true at all. Freud was a rigorous thinker, and was painstaking with his thought, which he changed as he made more and more observations.

I definitely understand that we feel a huge need to stigmatize him, that there is an overt resistance, its just rather funny to me that despite that we as a culture take so much of his ideas and concepts and internalize them. We get lots of weird dismissive attitudes like this, while not really arguing the thought itself.

Kettle logic was something he identified as phenomena, initially in dreams, but as we all anecdotally know, its pervasive. Our minds do not run on a principal of noncontradiction, but a logic of its own. I think that's profound and helpful to understand.

As someone who has studied and written about Freud extensively in an academic context, would just love to know where you identified inconsistencies in his thought.


It’s interesting that one implicitly assumes that there’s an AND between the arguments. Assuming an OR would remove the apparent inconsistency. :)


Oh gosh, I have stories about this sort of logic from my time in American high school and college competitive debate.

Usually, the affirmative team is proposing a plan that implements a resolution, and the negative team has to present arguments which convince the judge that either the plan, or the whole resolution is a bad idea.

A trivial example of the kind of "Kettle" logic that we had to deal with on the affirmative, is the belief that performative contradictions are simply part of "Competing Interpretations" and are totally fine for the negative team to use. This meant that it was common for a team to simultaneously argue that 1. The affirmative plan crashes the economy and 2. That Capitalism is a fundamentally unjust system and that the affirmative plan reperpetuates it. If you (the affirmative) argued against point 1, the standard plan by the negative was to jettison their arguements and concede to whatever affirmative points and turn them to help their 2nd point ("Well, your plan helps the economy so much that it makes capitalism that much more powerful!")

Smart teams argued that such "Performative Contradictions" and "Competing Interpretations" were fundamentally abusive. This was the correct strategy and by forcing the debate to devolve into these discussions of obscure theory we lost whatever educational value that the activity had about the topic.

Kettle Logic is the first time I've had a name for this that wasn't a debate community term-of-art.


I've never understood the grounds on which competitive debate is judged. It doesn't sound like what I would consider a good mechanism of persuasion. Is kettle logic actually a problem for a competitive debater?


During Nazi rule, there were many books written which the authors later found to be embarassing.

The common explanation was said to be: "I did not write that. They have forced me. And I did not mean it that way."


> That he had returned the kettle undamaged. That it was already damaged when he borrowed it. That he had never borrowed it in the first place

This is the logic of a sociopath.

I didn't hurt you, but if I did it wasn't that bad, and if it was that bad you deserved it.




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