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yrrosimyarin 39 points40 points 3 years ago

Re: Gracie Jiu Jitsu -- It was mostly that the first UFC was run by the Gracies, and they are excellent hype men above and beyond their ability as martial artists.

But there's much more to it than that -- martial arts develop to solve specific problems. Most of the origins of individual martial arts started with traditional soldiering, and then were adapted into sports so it was possible to train them without killing your buddies.

There are two major influences on the "art" aspect of this - the first one is that the martial origins of the sport influence its development. Are your techniques designed for young, strong men, or for anyone? Do they emphasize explosiveness and quickness (important in a general battle) or energy efficiency (more relevant to a duel). Think about the differences in a rapier vs a broadsword. A rapier is practically useless in pitched battle, but is excellent in a duel against an unarmored opponent. If you look at many of the judo techniques that form the origins of BJJ, they were designed to put a man in armor on his back so you could stab him to death.

Check out this video for a classic Judo takedown, and what the immediate aftermath was intended to be.

I train BJJ, and some of the techniques I use (especially the guard, which is BJJ's largest innovation) are incredible for "dueling," but are a horrible idea in a pitched battle.

The second aspect is the influence of the "sport" on the art. Without live sport and competition a martial art stagnates and atrophies. This has been shown time and time again (and is the primary thing that was shown in the early UFCs). Techniques must be drilled, practiced, and tested against an opponent who really doesn't want to let you do that. BUT, the side effect of that is that any art will adapt to the ruleset of the sport. Modern BJJ competitions look nothing like what Royce did in the UFC. It's actually a major controversy within the sport. Similarly, Freestyle wrestling techniques changed massively with the introduction of mats (I do not want to drive my knee into the ground to shoot a double on concrete or dirt).

And here in many cases we see the first two problems come together -- if you take a grappling art that was designed to get someone to the ground so you can stab them and turn it into a sport, you're not going to practice choking someone to death or breaking their arm. Your sporting ruleset isn't going to involve getting choked. And so your practiced techniques aren't going to involve preventing chokes. This is what happened pretty clearly with western wrestling.

If you take a boxer and put him against a wrestler, either the wrestler is going to get knocked out (because he doesn't practice not getting punched in the face), or the boxer is going to be taken down and pinned (because he doesn't practice escaping pins). The early UFCs were a constant parade of "crap I haven't trained to handle this." Even Royce Gracie took too much damage from a boxer to continue fighting in the tournament, even though he won that match.

All of that aside... that's only the art aspect. The other big influence is the athletes themselves. Is your guy just that much better at what he does? How big of a pool of athletes are you pulling from? How long have they been training, and how good is that training? Do your techniques allow or encourage that kind of competitive training? Grappling arts in general have a big leg up on striking arts in that aspect - I can spar full out nearly every morning and go to work that day. If I tried to do that boxing I'd have CTE for days.

UFC is currently heavy on ex NCAA wrestlers because in the US that is the best and largest feeder system for competent fighters. It's pulling some of the best athletes from around the country, drilling them hard in a competitive environment from kindergarten on up, and then pitting them against each other in constant competitions that let the really gifted fighters rise to the top.

Now, you put those top guys against a BJJ practitioner with no other prep, they're going to get choked out. But give them a few months or years to learn the basic defenses and they'll destroy most BJJ only guys in the UFC because they as individuals have been built into that much better of a grappler/fighter.

So, Brazilian Jiu Jitsu isn't that special. It's a great art, I love it, I train it every day... but the techniques the Gracies were using were centuries old. It was just a particular combination of the right format (individual duels with fewer rules than their opponents were used to training under), awesome practitioners (athletic guys who had been training since childhood in that specific art), and a whole lot of Gracie marketing.

blackbootz 2 points3 points 3 years ago

I tore my left MCL the third time training BJJ. On doctor's orders to take it easy. I'm fascinated by BJJ, though. Sam Harris has a wonderful write-up called The Pleasures of Drowning that I wonder if you've read.

What's your motivation for training daily?

yrrosimyarin 2 points3 points 3 years ago

Ha, I'm completely obsessed. I came to it from the self defense side of things - all the trainers I respected said BJJ was about the best art for practical applications. So a buddy and I looked up a local gym.

And oh man I fell in love. I don't think a normal person realizes the depth of skill difference there is. The complexity. I remember being amused reading about "Chess Boxing" - now I realize that the martial art itself is plenty complex and mental on its own. The blend of "always something new to learn" with "you could always do the things you know better" just keeps me coming back.

I've read the Harris essay, although I forgot he was the one who wrote it. Captures it pretty well.

I'm just a blue belt. Someday I'll hopefully know what I'm doing.

Hope your MCL heals up fast!

PokerPirate 23 points24 points 3 years ago

The question about the origin of furries was particularly interesting to me. I've asked it on /r/askhistorians [1], so hopefully it gets a good response.

[1] https://www.reddit.com/r/AskHistorians/comments/9p6e55/when_did_furries_people_who_dress_up_in_animal/

newworkaccount 17 points18 points 3 years ago

Fingers crossed. I will go upvote you (I love AskHistorians).

Something like this has been lingering in the back of my mind, too, for years, though it doesn't ever seemed to have explicitly jumped out to me until I read it.

First, there are so many furries. I suppose if his proposition that they are tech workers is true, it's possible they are overrepresented on the internet, which answers a little bit-- they have an active con scene because they have had a ton more years of being able to congregate and organize with each other online-- but also just pushes it back a step, in a way. Why should that be especially interesting to tech people?

Second, as above, the fetish oriented aspect seems largely overrepresented. Furries seem to divide themselves into those for whom the persona is platonic (maybe in more ways than one!) and those who are interested in it sexually.

Why it seems overrepresented to my mind: many fetishes, even if I don't share them, at least lend themselves to an understanding of how they came about.

So a foot fetish: how often do we ever touch another person's foot? It is nearly as non-verbally forbidden as normal erogenous zones, it's often draped in specifically gendered and often sexualized apparel (shoes), and, in general, it is a part of someone's body, and so it more or less makes as much sense as any other body part fetishism.

And I can see how it might develop: maybe your first teen boyfriend or girlfriend used their feet to surreptitiously tantalize you under a blanket, under the watchful eye of your parents. Oops! Now you've got a foot fetish!

And I feel like most fetishes are this way: they may not do it for me, but I can think of reasonable circumstances that would cause them.

Furry fandom? I honestly have no idea. Mall Santas? Suited characters at Disney World? Early sexual experimentation with an animal in the household (poor Cory!).

My best spitball at the moment is the guess that early tech geeks were the first to adopt avatars and personas that were entirely up to their imagination. This is the only time in history where that was actually available to people as an option.

So perhaps it is a form of body dysmorphia-- a desire to become their idealized avatar because they don't identify with their actual body (or dislike it)?

And considering autism spectrum disorders are pretty common in the tech world (ime), perhaps they also don't have the usual and immediate sensitivity of knowing that people will severely judge you for it.

Obviously autistic people could probably and partially predict this reaction: what I mean is that they don't have the vivid theory of mind that allows you to feel instant and excruciating embarrassment at the idea of doing something socially unacceptable. Past memories where they learned they acted embarrassingly: perhaps. But maybe not at first.

Anyway, this is a just-so story for sure, and of course could only explain early and on the spectrum internet users at best. (And likely doesn't explain even that!)

I do note that unusual and culture-bound body dysmorphias seem to be fairly common: Asian shrinking penis, pregnant women believing they will birth puppies, clinical lycanthropy, etc. And transformation tales are found in the myths of every culture I know.

So it feels like there is some predilection in the human species to imagine itself with a different kind of form.

Additionally I would note that social clubs for societal outsiders seem to have inertia once established: maybe you don't necessarily feel like a real vampire, but claiming to/pretending to/wanting to and gaining a social circle may make converts out of those without strong convictions on the matter.

yellowstuff 3 points4 points 3 years ago

I have a vague memory of someone theorizing that Furries rose to prominence as a response to the AIDs epidemic. Sex had become scary and deadly, so people coming of age sexually were attracted to something safe, physically distancing, and reminiscent of their childhood.

p3onร‡โ€  2 points3 points 3 years ago

this is pretty close to my theory -- except minus the aids part. furries are largely pretty nerdy people, ie people with low to middling social status in adolescence. i was one of these people, as im sure many others here were, and i can remember how stressful the idea of dating and selection by the opposite sex were. i can remember, like you say, how safe and welcoming children's media was on the scary threshold of adulthood, and how much of the adult world seemed ugly and difficult; so maybe your aids hypothesis has something to it.

i can see this feeling contributing to becoming fixated on the aesthetics of children's cartoons while your hormones are beginning to burn pavlovian boner-fuel into your subconscious. the internet, as every kid knows, is a place where you can experiment and find the things that aren't accessible in your real life. so when you inevitably begin experimenting sexually, maybe a community where people use cool cartoon avatars and role-play fantastic characters can seem like something appropriate to your (still in many ways childlike) identity, where you can safely act out those experiments. with enough time and relationships it becomes a major part of your identity, maybe even ingrained into your libido.

33_44then12 3 points4 points 3 years ago

Fat people can look good in a fur suit. There are lots of fat people today.

newworkaccount 6 points7 points 3 years ago

Sure, this is part of what I had in mind when supposing it to be a possible body dysmorphic disorder. A counterpart to anorexia/bulimia: rather than fix your food/weight issues in an unhealthy way, you cover yourself with a costume that hides yourself.

That being said, I don't know of any evidence that this is actually true. A priori I feel like a turn to fat acceptance is the easier psych battle: rather than a partial cover-up some days, why not convinced yourself you're beautiful you are, every day? Society is cruel to obese people, but I am sure fursuits are way more frowned on.

I am also not convinced quite that this behavior is pathological; i.e. that they do it because of something wrong with them. At least some furries seem like otherwise well-adjusted people. Perhaps they really aren't, but I don't see the necessity of pathology as being obvious.

Tophattingson 10 points11 points 3 years ago

I've asked it on /r/askhistorians

There's also this. It's not about when it started. Instead it describes a series of events in the late 90s that may have played a central role in the evolution of that community. I don't really have any other leads to suggest.

SchizoidSocialClubIQ, IQ never changes 19 points20 points 3 years ago

Disney.

My opinion is somewhat freudian. During early childhood an event leads the child to associate sex with that event. A form of imprinting that reinforced by masturbatory fantasies about the stimulus results in a paraphilia. A spanking can lead to to BDSM, potty training to watersports etc

With more and more children exposed to anthropomorphic animals, and with artists having a better understanding of neoteny and other ways to make cartoon characters more appealing, there are more opportunities for children to imprint on them, leading to more furries.

The children susceptible to paraphilias tend to be boys exposed to certain hormonal abnormalities during development. Maybe, like in the case of autogynephiles, there is a correlation between traits that make one professionally successful in the tech world and the paraphilia.

Or maybe being a furry is an expensive thing and price acts like a filter.

bulksalty 13 points14 points 3 years ago

Disney's Robin Hood came out in 1973, which would be about right for children watching in the ensuing years reaching sexual maturity in the 80s.

yrrosimyarin 7 points8 points 3 years ago

Anthropomorphic animals were a major portion of my childhood... I wouldn't say heroes or role models, necessarily, but hugely influential characters and stories. Seems like a reasonable extrapolation to identity/attraction.

BadSysadmin 2 points3 points 3 years ago

This is interesting viewing on the topic

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https://www.youtube.com/watch?v=8aF2GxWi7Ag

RovingSandninja 3 points4 points 3 years ago

This is definitive. Closest thing we have right now to a documentary on furry culture.

sethinthebox 1 point2 points 3 years ago

The furry agenda is as old a humanity and the evolution of shamanic ritual magic.

Dormin111 22 points23 points 3 years ago

Photographs of exceptionally beautiful women from the 1800s or early 1900s strike most people are being remarkably drab and unattractive. Given the stability and cross-cultural consistency of beauty ratings, it seems unlikely that it is merely a matter of shifting norms or preferences or fashion. What is going on? Has cosmetics and hairdressing really advanced that much or should we look at explanations like vastly superior vaccines, elimination of childhood disease, superior nutrition etc? (Large gains in means would not be unprecedented: when we look at photos of children or people from those time periods, one common observation is how short, scrawny, and stunted they look - and indeed, as an objective fact they were and things really have improved that much.)

Two implications of this fascinate me -

  1. Will this trend continue? If I could magically see the line up of the top 10 Hollywood starlets and A-list musical artists in 2050, would they be the most stunningly beautiful women I've ever seen? Or alternatively, will the every-day, middle-class, average looking 25-year-old in 2050 look like Scarlett Johansson?
  2. Will beauty standards continue to to fracture and split off in many different mutually exclusive directions? If you look at the famously beautiful stars from 50+ years ago, they tend to look very similar - modest bust, long hair, big eyes, the "classical look," etc. But today, we have "sex symbols" as diverse as Kim Kardashian, Niki Minaj, Taylor Swift, Gal Gadot, Emma Stone, etc. Maybe the best example of this is trends in pornstars, which used to converge on the "blonde bimbo" archetype, but has fractured in a hundred different directions between "girls next door," "college cheerleaders," "milfs," etc.

SchizoidSocialClubIQ, IQ never changes 13 points14 points 3 years ago

East European women were considered ugly until the fall of communism.

It is possible that due to living conditions for poor people in the Russian Empire many of them were marred by their hard childhood and difficult life in general. Due to the Iron Curtain this image was not updated until the 90's when the West discovered a new generation that grew up in much better conditions during the Brezhnev era.

This increase in beauty could be parallel with the Flynn Effect for intelligence and with the well-documented inter-generational increase in height. Better food and health care during pregnancy and childhood results in taller, smarter, more attractive people.

But there is a limit on the influence of developmental and environmental factors. When environmental factors are optimized there is plateau which we probably already hit in developed countries.

Right now we are in the middle of an obesity epidemic that is reducing the general attractiveness of the population.

If obesity gets worse then maybe we are at the end of a period of Peak Hotness when environmental factors were good enough to ensure optimal development, but no so good that they caused generalised obesity.

[deleted] 8 points9 points 3 years ago

One thing is that Gwern explicitly said "exceptionally beautiful" women of that time. Even if East European women were considered ugly in general, the most beautiful women were still considered beautiful. Think of all the Russian femme fatales in the James Bond movies. Or the figure skaters and gymnasts of that time. A quick image search shows women who are still attractive to modern eyes.

[deleted] 7 points8 points 3 years ago

Is it a trend? Or is it something specific to that early time period? I would look at photographs over time and try to find when people become โ€œattractiveโ€ to modern eyes. See what changed around that point.

I vaguely remember something about how you were not supposed to smile in portraits. Maybe we are keying off the lack of expression in those old photographs.

throwfaraway667 5 points6 points 3 years ago

With the caveat that I know little of art history, this appears to be also true of old paintings. Perhaps it's partly because art, including nudes, was not supposed to be arousing and because a large proportion of the "old masters" were gay with no eye for female beauty. I think we get genuinely hot-looking women in European art only in the 19th century, e.g. in Bouguereau and Renoir, but I'm interested in seeing counter-examples.

[deleted] 8 points9 points 3 years ago

because a large proportion of the "old masters" were gay with no eye for female beauty.

I'm curious what evidence there is for this. There was a fad several years back of randomly picking historical figures and "proving" they were gay based on a florid letter to a friend or some such thing, but that's all I can recall.

zonules_of_zinn 8 points9 points 3 years ago

additionally, were gay men less able to discern female beauty?

seems to me that contemporary gay men tend to be more discriminating about female beauty than straight men. blatantly stereotyping here, but the typing goes that they'll judge women more harshly for their eyebrow overgrooming, mismatched foundation, complexion, shoe choice, etc than a straight man who could fall in love with an ugly women and consider her beautiful.

serfal123 8 points9 points 3 years ago

We have sculptures from the ancient world which look as beautiful as women are today i would say. Perhaps you mean only medieval art though?

Dormin111 13 points14 points 3 years ago

Some of my answers at a glance -

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what is personal productivity and why does it vary from day to day so strikingly, and yet not correlate with environmental variables like weather or sleep quality nor appear as the usual kind of latent variable in factor analyses?

I think itโ€™s worth spending my entire life trying to figure this out.

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Does listening to music while working serve as a distraction, or motivation?

I sometimes listen to music while working, but only instrumental music โ€“ usually techno or classical. I find video game soundtracks are especially effective. But music only motivates when Iโ€™m already โ€œin the zone,โ€ otherwise it takes up too much cognitive space.

โ€‹

why did Jean Calment live so many more years than other centenarians, breaking all records and setting a life expectancy record which decades later has not just not been broken, but not even approached? Which is extraordinary considering that she smoked, medicine has continuously advanced, the global population has increased, life expectancy in general has increased, and the Gompertz curve implies that, with mortality rates approaching 50%, centenarians should die like flies and ever closer in age to each other.

why do humans, pets, and even lab animals of many species kept in controlled lab conditions on standardized diets appear to be increasingly obese over the 20th century? What could possibly explain all of them simultaneously becoming obese?

Does moderate alcohol or wine consumption have health benefits, or not?

Nutrition research is still shockingly primitive. I suspect individual genetic variation is dramatically understated. Like, the idea of there being a universal daily requirement for particular nutrients is probably absurd.

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if child abuse and emotional neglect is so harmful and there is nothing more to it than that, why does it appear in the biographies of so many people who achieve greatness, often middle/upper-class? If it increases motivation and creates a drive to mastery, is there any way to capture the benefits without being evil?

As in all cases of great struggle effecting human behavior, child abuse probably creates a larger variance of outcome than non-abuse. Some kids gain strength from fighting the adversity or independence from dealing with neglect, while other kids succumb to the pain.

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Why did it take until the late 20th century for Brazilian Jiu-Jitsu to develop and the Gracie family crush almost all other unarmed martial arts at the start of MMA, when humans have engaged in unarmed combat for millions of years and every major country has long lineages of specialized competitive martial arts and tremendous incentive to find martial arts which worked and quick feedback loops?

MMA didnโ€™t exist until recently, and before then recreational combat was based around insular communities, and before then hand-to-hand combat hadnโ€™t been especially useful in the military for thousands of years.

newworkaccount 9 points10 points 3 years ago

what is personal productivity and why does it vary from day to day so strikingly, and yet not correlate with environmental variables like weather or sleep quality nor appear as the usual kind of latent variable in factor analyses?

If 10,000 butterflies flap their wings across the world, none of them are statistically significant.

This section on factor analysis in psychometrics at Wikipedia rings true:

"...each orientation is equally acceptable mathematically. But different factorial theories proved to differ as much in terms of the orientations of factorial axes for a given solution as in terms of anything else, so that model fitting did not prove to be useful in distinguishing among theories." (Sternberg, 1977). This means all rotations represent different underlying processes, but all rotations are equally valid outcomes of standard factor analysis optimization. Therefore, it is impossible to pick the proper rotation using factor analysis alone. Factor analysis can be only as good as the data allows. In psychology, where researchers often have to rely on less valid and reliable measures such as self-reports, this can be problematic.

Interpreting factor analysis is based on using a "heuristic", which is a solution that is "convenient even if not absolutely true". More than one interpretation can be made of the same data factored the same way, and factor analysis cannot identify causality."

As in all cases of great struggle effecting human behavior, child abuse probably creates a larger variance of outcome than non-abuse. Some kids gain strength from fighting the adversity or independence from dealing with neglect, while other kids succumb to the pain.

Tautological, I'm afraid. "The kids who survive survive, and those fail fail."

Possibly it's an artifact of an availability bias. The backgrounds of the famous are only notable when they are bad/create a narrative of triumphing in adversity.

Additionally, it may be that bad childhoods are quite common; more common than we think. In that case we can separate out two groups, those with bad childhoods that succeed, and those with bad childhoods who don't...but that doesn't mean there are meaningful differences between the two (i.e. a lot of people have bad backgrounds, and these things are unrelated to success).

Note that it can be irrelevant to success and still relevant for failure: maybe people are successful for entirely unrelated reasons (i.e. their success has nothing to do with abuse), but those who fail often end up failing because they were abused.

MMA didnโ€™t exist until recently, and before then recreational combat was based around insular communities, and before then hand-to-hand combat hadnโ€™t been especially useful in the military for thousands of years.

Precisely. It's actually never been the norm in organized fighting/war, to my knowledge, and all non-modern forms I know of are either metaphysical (awaken your chalkra; harmonize your chi; empty your mind) or public spectacle (where rules are arbitrary and primarily to avoid injury and be enjoyable to watch, real fighting is neither).

Interestingly, hand to hand combat seems to be more common in modern conflicts than at any other time; at least, the Marine Corps seemed to believe so, when I was in.

The reason given is that in modern warfare when you run out of ammunition, you have little or no time to fix bayonets, and modern rifles are atrocious to use as clubs (long rifles have nearly all the weight in the buttstock/lower receiver to reduce arm strain, but are too thin and too hot after firing to grip the barrel end and bludgeon with; or, you have a carbine, which is shorter than your arm by roughly half, making it useless). Additionally, due to fighting insurgencies in urban areas, you are often spatially near the enemy.

So people close to grapple the enemy to prevent them from firing their own weapons. Often they throw their own weapon at their target when rushing.

There was actually a bit of a push to have combat units roll with fixed bayonets 24/7 for awhile after the Marine Corps gathered this data; as far as I know, it was dropped due to there being few situations where U.S. troops were running out of ammo and a lot of accidents with the bayonets. (To some extent because they weren't issuing bayonets during training, same as they don't distribute live ammo except at ranges, to make it safer. But when you make someone carry a rifle 24/7 without a bayonet, and then suddenly it has one all the time, you can see the kind of absent-mindedness that might follow.)

33_44then12 14 points15 points 3 years ago

Pankration was ancient Greek MMA.

https://en.m.wikipedia.org/wiki/Pankration

Anything goes but for eye gouge and groin strikes. It was in the Olympics. Best fact: Spartans were not allowed to compete because they would kill people.

I also get the idea that steppe culture "wrestling" was closer to MMA but I can't find sources on mobile.

Finally, the first UFC was a bit worked. It was set up for Royce Gracie to win as advertising for Gracie Jujitsu.

newworkaccount 4 points5 points 3 years ago

Indeed it was. "Gates of Fire" is a long-time favorite of mine, and first sparked my interest in the Spartan world shortly after I joined the Marine Corps. (It's on the Commandant's reading list for enlisted Marines and is often required reading in officer training of various types.) Of course, it's a novel that takes a large number of liberties, even if it was clearly well-researched.

In any case: first, yikes, the Wikipedia page is pretty wretched. It uncritically regurgitates ancient writers' descriptions and appears to have been written by an MMA fan that had a strong urge to identify MMA fighting with pankration.

Also it says that Philo in the 2nd century AD was probably a pankration fighter...? Huh? A 2nd century Hellenized Jew that lived in Roman Egypt was practicing pankration...? While not impossible, since Roman rule through the 300s AD was sort of the heyday of the Olympiad, the only source we have for the claim (that I'm aware of) is Philo reporting what happened in matches that he watched. Certainly Alexandria was very Greek, but we have very few sources for his life: a few self references and some bits of Josephus (who was an oft-altered text under Christian copyists).

Anyway, I think the only comment I have on it is that pankration strikes me more as a kind of a virtue builder/virtue tester rather than something the Greeks viewed as an essential combat technique.

Fighting --> toughened Lakedaรญmลn--> they become good warriors and earn glory in combat --> good warriors are good fighters --> fighting --> ...

Like Crypteia, while it was also combat practice, but not necessarily done for that reason, so pankration was probably seen as both the sign of a good warrior as well as preparation for being one...but not necessarily a means for direct combat.

Against this view would be the explicitly martial aspect of many of events in the Olympiad, which contemporaries noted as good for at least partially this reason.

It also seems to be the case that the Spartans, at least, practiced techniques that were analogues of phalanx fighting techniques-- in particular, hammer fist techniques that resembled spear use over a shield wall.

I am still doubtful that this was explicitly combat training, in the sense that Greeks planned to use it as a primary means of warfare; rather, at best, this was something you did if the shield line broke and so did your weapon. Phalanx tactics in general have completely failed if you are engaging in hand to hand.

Now I'm quite interested in the steppe martial arts you're thinking about-- do let me know if you remember! It's not something I know anything about.

Re: UFC, pretty interesting. I don't keep up with it and had no idea that the first match was...kayfabe, I guess? and the audience marks. Was this common early on?

[deleted] 8 points9 points 3 years ago

[deleted]

33_44then12 5 points6 points 3 years ago
  1. Spartan's first (and second and third) obligation was keeping the Helot's terrorized. There were seven Helots for every Spartan. That is why they were so reluctant to go to war. Hand to hand is handy when you are getting jumped by a couple Helots pissed at you. In phalanx battle you go to the ground you get stepped on by everyone, no shield etc. No good.

  2. The first UFC was worked in the sense the rules favored Royce. Wrestlers could not wear boots. I think only Royce had a gi.

Here is a podcast about the first UFC. https://30for30podcasts.com/episodes/no-rules-birth-ufc/

I think I saw a full 30 for 30 on it. Ken Shamrock thinks he got rooked.

moridinamael 4 points5 points 3 years ago

Khabib Nurmagomedov is on a 27 win streak in MMA and his expertise is listed as on Wikipedia as โ€œSambo, Judo, Pankration, Freestyle Wrestlingโ€.

Interesting that jiu-jitsu is absent from this list but Greek-derived and Japanese-derived wrestling/takedown styles are present.

gwern 5 points6 points 3 years ago

This section on factor analysis in psychometrics at Wikipedia rings true:

That's not an answer, any more than 'neglect increases variance in outcomes' is actually an answer to that question either. Factor analysis works ridiculously well in psychology, regardless of the technical details of how exactly you prefer to rotate your factors or principal components or whether you are using self-reports.

newworkaccount 1 point2 points 3 years ago

Well of course, and I didn't ever claim that it was; I implied that the difficulty may partially lie in how difficult factor analysis is to do well.

Quite frankly it is one of the reasons why psychology is at the forefront of the replication crisis: they are notoriously bad at statistics, and so (apparently) are their peer reviewers.

It is becoming less common now since they've oriented on it, but I have (multiple times) seen studies where they reported a statistically significant result, but failed to report an effect size altogether. Or recommended a course of action because their result was very statistically significant, but the effect size was tiny.

I'm not sure we can avoid being anecdotal here, and I don't disagree that factor analysis can be done correctly and is useful when it is. But I don't think it is being done well very often, and I think it's being used in situations where it doesn't apply.

I'm not familiar with the literature of your particular question; just making a guess from overall understanding of that kind of literature. If you assure me these studies were rigorously done and the body of evidence is wide and deep, I'll take you word for it.

I/O psych (which I assume this falls under) is not my forte.

[deleted] 3 points4 points 3 years ago

[deleted]

newworkaccount 3 points4 points 3 years ago

A marine in Iraq was forced to beat an insurgent to death with the man's own machine gun when he came around a corner and the marine's own weapon was unloaded

You sure you mean "machine gun"? Usually for the U.S. military that refers to crew-served weapons: bulky weapons that weigh 20-30lbs that would be really awkward to beat someone to death.

Very few Iraqis had true machine guns after the initial invasion/surrender of the Republican guard.

Generally they fielded Russian and Yugo manufactured RPKs, which is essentially a drum fed Kalishnakov with auto capability. While they fielded it in a light machine gun role, and it's often called a light machine gun, there's not much that distinguishes from an AK-47 other than higher capacity and pod legs.

Also, where did you hear this story? It's a rather unusual circumstance for a Marine to be in true MOUT combat environment without a magazine in and a round chambered (i.e. Marines keep their weapons loaded if they're in the kind of place where they bump into people with machine guns that want to kill them).

If it's a true story then he's a lucky bastard (brave too). If the enemy had been paying attention he'd be dead. (Though the inattention itself wouldn't be strange; Iraqi insurgents had very poor discipline and aim, for the most part.)

Affixed bayonets are also terrible for the kind of situations a modern soldier is likely to find himself in melee. They're awkward, ungainly, and relatively fragile for the purpose they're likely to be put.

Yeah. They're especially terrible for house raids. Doorways way too narrow for that shit, easy to stab someone else on accident in a stack on a door, and if someone falls you risk getting impaled.

We were issued Ka-Bars with a bayonet mounting point but none of us mounted them, that I recall. I believe company leadership strongly implied they ought to be left off, without outright forbidding it.

The only time I ever used one was when we were clearing a big and abandoned carpet warehouse. Pretty good risk that someone might be rolled up inside of a carpet waiting to get the drop, so that was how we ended up deciding to check them-- gouge in from the side, out of vision of the roll.

It sounds stupid and it felt goofy, but you never know. Shit is risky enough without taking risks you don't have to.

Historically, and I suppose as the British demonstrate, modernl, the primary utility of an affixed bayonet is the psychological impact during a charge - break the enemy before it comes down to actual exchange of blows.

Sure. Professional armies don't fight like this anymore; you may charge entrenched defensive structures but there's just no battle lines such that a bayonet charge would be useful. Almost anywhere open enough for a charge can and will be 'naded/mortared/artilleried/Warthog'ed/air striked instead.

Typically in that case you really only need to set up interlocking fields of fire and suppress the enemy in place: basically, pin them down long enough to be an easy air support target.

Ofc you don't always have air on call...

Even during the days of flintlock muskets, bayonets only account for 2-5% of all casualties as almost always either the defenders or the attackers break and run before getting "stuck in".

Yeah, exact same problem that saw spears disappear except for cavalry charges; they're hard to pull free of someone's body. Similarly for greatswords. Even the ubiquitous medieval broad sword was actually much closer to what we'd call a short sword, despite its fictional depictions.

A solid knife or even a length of table leg with some hob nails in the end of it has historically served soldiers much better as a melee weapon.

Knife all the way. Easy to get to, easy to carry, easy to use, easy to pull out, easy to clean, lightweight, and so much utility beyond its combat role.

Knife, paracord, and duct tape were essentials I would have never done without.

[deleted] 4 points5 points 3 years ago

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cactus_headProud alt.Boeotian 2 points3 points 3 years ago

I sometimes listen to music while working, but only instrumental music โ€“ usually techno or classical. I find video game soundtracks are especially effective. But music only motivates when Iโ€™m already โ€œin the zone,โ€ otherwise it takes up too much cognitive space.

When listening to music normally I get distracted because I want to choose the next song every time the current one finishes, except when I put on an entire soundtrack and just let it run through which is uncommon. But I also have some looping tracks I made from videogame and anime songs and when I put those on it's easier to get in a state of flow than without the background music. Part of the reason is that I like to set little goals and try to get as many as possible done within every loop, and doing this 5-10 times is a good way to get into flow.

thedessertplanet 2 points3 points 3 years ago

Thousands of years? How does your history work?

Dormin111 7 points8 points 3 years ago

I meant to imply a distinction between unarmed combat and armed melee combat. Literal "hand"-to-"hand" combat hasn't been important for a while.

thedessertplanet 3 points4 points 3 years ago

Ok, that makes more sense.

Unarmed brawls do happen, but the major focus of concentrated efforts (like military) has been on use of weapons. (And usually more than two participants.)

MMA rules are also rather specific. Eg the mats they are on make different techniques viable than if you were fighting on asphalt or concrete streets.

partoffuturehivemind[the Seven Secular Sermons guy] 11 points12 points 3 years ago

If child abuse and emotional neglect is so harmful and there is nothing more to it than that, why does it appear in the biographies of so many people who achieve greatness, often middle/upper-class?

This one seems easy. Most of the children were abused and neglected as a matter of course. From The History of Childhood:

The history of childhood is a nightmare from which we have only recently begun to awaken. The further back in history one goes, the lower the level of child care, and the more likely children are to be killed, abandoned, beaten, terrorized, and sexually abused.

โ€‹

Evan_ThEvan รž 7 points8 points 3 years ago

That's possible.

However, my immediate speculation is "Child abuse knocks children's development off-course in a practicably random direction. A few end up going in a positive direction, but for the vast majority it's highly negative."

This is off the top of my head; I have no way of knowing whether it's true. However, it does seem to fit what evidence I can think of off the top of my head.

helaku_n 1 point2 points 3 years ago

Yes, probably only strongest/fittest โ€“ be it physical or mental fitness/strength โ€“ children survived until some recent time (the beginning of the past century). And it is so more or less regardless of class.

HeckDang 9 points10 points 3 years ago

These are pretty interesting. Some of them I have a hunch, some are very mysterious.

It would be cool if lots of people would take notes like this to look over.

newworkaccount 32 points33 points 3 years ago

One thing I'll note is that I agree with him that our society has a penchant for description as explanation, and insufficient explanation in general.

I often find myself quite certain we haven't actually solved something that is supposed to be "solved", or that we're nowhere close to a solution that is nonetheless widely believed to be "just a matter of putting in the work".

Usually this is because, when I think about the solution, it seems obvious that if we really understood x, we would also straightforwardly be able to (do, invent, understand, treat, exploit, sell) y and z. But we can't. Ergo we clearly don't understand x even if we have written textbooks about it.

Consider psychiatry as an example. (And I am not a Scientologist, nor do I consider it "useless", etc.)

No one seems to emphasize the curious fact that when you go to a psychologist, their diagnosis is more or less a group of symptoms.

Usually you go to the doctor with symptoms (high fever and stiff neck), and then they determine the root cause (bacterial meningitis) and treat the disease (Rx antibiotics).

At the psychiatrist you go in with a list of symptoms (feeling depressed), and then they officially list your symptoms back to you (diagnosis: depression) and give you medicine to treat your symptoms (Prozac).

They don't treat the root cause because they don't have any idea what it is. And in fact they don't understand how the medicines work, either, or for whom one will work, which is why many psych patients try a series of different medications. The gold standard in psychiatry is essentially throwing shit against a wall to see what sticks.

Now, this is a phenomenally difficult field, and I'm not interested in abolishing psychiatry or suggesting that it's all worthless (because I don't believe that, though you might not know it to read the replies I get).

I find it quite odd that this isn't common knowledge. Psychiatry has adopted all of the trappings of internal medicine but is not, in practice, at a commensurate level of understanding.

Chemical imbalance?

First of all, the statement has no information content. What does that actually mean? "Your brain isn't working correctly, so it's imbalanced"? Ok, but imbalanced how? Tell me which chemicals, where, and what they ought to be doing.

But we can't. The National Institute of Mental Health was doing spinal fluid draws in the 70s that showed serotonin metabolites-- i.e. the evidence of active serotonin use/processing-- didn't track with depressive symptoms at all.

We've known for decades that serotonin levels have essentially nothing to do with depression. Yet I had a friend whose psychiatrist explained it in exactly those terms. Journalism explains it that way too.

It only took us ~20 years too to figure out that Zoloft accumulates in the brain's membrane. Good thing? Bad thing? We honestly don't know. We didn't even know it was happening. Hell, we taught for ~100 years that axons only communicated 1 way. It's still in some intro neuroscience textbooks.

And again, I don't view this as a terrible indictment of the system. I don't think it's some terrible indictment of a thoroughly BAD THING.

I just view it as baffling that we talk about this as though we've got a good handle on it. Clearly we do not.

As a last side, one thing I don't think people necessarily think about is that nearly every expert relies on the valuation of their expertise for money: therefore every expert has a strong case to oversell their expertise/the state of knowledge in their discipline.

Now, I haven't a clue how common it is, nor how you would find it out.

But I often hear people ask, "But what motivation does a pure scientist have to lie to me?"

Well, the answer is that they make money because you see their expertise as valuable. I am not saying they are, in fact, doing so-- just suggesting they certainly have reasons for wanting to do so, even if they do not.

I don't know what the answer to that problem is, though; we have no choice but to trust experts. No one can gain expertise equivalent to an expert's in everything they need help with; we always end up having to trust other people when they say that x or y is how things work.

Pretty long tangent, I'm afraid.

[deleted] 5 points6 points 3 years ago

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newworkaccount 5 points6 points 3 years ago

I agree with your central thesis but something that is not discussed enough is the misplaced incentive for payment / self-interest and psychiatry/therapy is the perfect example. If their payment structure is repeat business, why would they solve the root issue and not just symptoms? Cynical view but it should be taken into account. If I had an mental illness I want treated, I would trust a professional who would be willing to forego payment until the problem is fixed or at least reduce recurring payments until something is happening, at least in theory. In practise they would not be paid enough to live on so no professional would work that way.

I agree. A lot of disciplines suffer from the fact that expertise and information is often locked up into partisan institutions that misalign incentives: people who know how to regulate the oil industry only gain that knowledge by being able to make a living at oil companies, etc. Stuff like that.

The hard part, I think, is that I don't know how you avoid this. Obviously the answer is not to require non-profits in every industry, or to have the government do so, either.

Indeed, medicine specifically is absolutely full of misalianged incentives.

One egregious example would be the number of sleep doctors who also do DME equipment: that is, the same doctor who diagnoses your apnea also makes money if you get your CPAP machine from them. It's easy to see how perverse that incentive is.

(Generally it is sold as convenient for the patient...one stop shop, you only have to deal with doctor that you trust and no one else...as well as good for the doctor, in the sense that using the same machine for everyone makes troubleshooting/dealing with compliance data/knowing about common equipment failures, etc.)

Probably the most interesting thing is that the limited data we have appears to show that it isn't causing wide scale corruption: when you compare doctors who do DME to those who don't, the equipment prescribed and the number of diagnoses are roughly the same.

Re: psychiatry, funnily enough, they have every incentive to cure their current patients and bring in new ones.

The reason is threefold:

One, there's a huge shortage of psychiatrists, psychologists, and counselors, with huge waitlists for new appointments. The supply of patients is so large that they would stay full even if they cured every single patient tomorrow. Especially true the more rural the area is.

Two, their population often runs into difficulty with payment and/or regularly miss appointments. Portions of the fee they would charge can usually be written off if the patient is unable to pay or they were available but the patient didn't show; these write offs, where available, scale directly with number of patients. So oddly enough the doctor is better off getting in 10 pts without pay than 5 as long as the time used is similar. (This is one reason most doctors often 'double-book' their appts, though far from the only one.) Admittedly this is not always true everywhere. It will depend partially on the country, how the practice is set up for tax purposes, etc.

Third, while this also changes from place to place,--as a rule of thumb, new patient appts often bill for double the time but significantly more than double the fee; generally speaking insurance companies won't reimburse this more than once without a fight, and sometimes the new pts don't take very long to process.

Again, this isn't always true, and reimbursement rates in psych have started to plummet because they are becoming a huge cost for insurance companies relative to other costs.

One perverse incentive I would note, however, is that psychiatrists are absolutely ripe for pharma company kickbacks.

Why? Because they have the most homogenous pt population of any specialty, and therefore they prescribe more drugs of the same class or indication than any other discipline.

99% of what they see is ADHD, depression, bipolar depression, OCD, and anxiety. (Private practices rarely have large schizophrenia numbers, largely because schizophrenics are frequently non-compliant with treatment and many don't pursue treatment voluntarily.)

That means if they can get a kickback for prescribing a depression drug, they (and the pharm company) will make way, way more money than an internist who prescribes a new antibiotic or a neurologist who prescribes a dopamine agonist for Parkinson's, simply because their pt populations have a lot more diagnoses going on.

newworkaccount 4 points5 points 3 years ago

And there's your answer but the more ontological higher explanation would simply be self-interest (ego protection, social inclusion etc..). Sad as it is, it's part of reality and I don't think much can be done about this other than creating a more tolerant atmosphere for failure or perhaps even better, admitting failure without the PR context.

You know, I think this applies in practical pursuits to some extent-- medicine is a good example, this has been an issue that's been at the forefront of that community's mind for some time. (I think the public dialogue started with Atwul Gande, this particular time, but like all disciplines there are always half-completed reforms and half-assed decays going on around the same time that something crystallizes as THE NEW BIG IDEA.)

Discussion of nosocomial (medical care caused) fatalities and complications have been brought out into the open and preventative measures like Rx contraindication alerts, checklists/algorithms for certain decisions (like myocardial infarction), and even mandatory post-fatality meetings to discuss what error led to it and what could be done to prevent it in the future.

However, I don't think this probably applies to academics. My impression is more that the innovation (or claimed innovation) gets more sunshine. That the sentiment is less that failure is unreportable-- it's still good-- but new is considered the best, and so it's what people aim for. (If you can pad your tenure track with discoveries instead of negations...well, no one ever won a Novel Prize for disproof.)

Additionally, the higher the expertise, the fewer people who actually know enough to dispute you. Your primary care practitioner will take your oncologist's word for something 99% of the time, because oncology, like most medical disciplines, is now so specialized that only oncologists really know what is going on. In turn they'll take your neurologist's word on the cognitive difficulty caused by radiation therapy...etc.

This reduced pool of those "in the know" also raises a different issue: peer review will often be conducted by people you know in your field, and by publishing negative results you are also chipping away at what someone else's career got built on. Etc.

So people are incentivized to find smaller and smaller niches, and to be very careful how they evaluate those that they will work with or depend on for evaluation later.

Note that I don't know this: it just seems likely from how people work.

gwern 7 points8 points 3 years ago

well, no one ever won a Novel Prize for disproof.)

Michelson did, for the Michelson-Morley physics experiment disproving the 'ether' for light. But that's the only example I can think of offhand (stress/ulcers?), so perhaps the exception that proves the rule.

newworkaccount 3 points4 points 3 years ago

Why is the CEO let go off just because the stocks slow down? He or she should be given a choise to solve the scandal or failure to meet expectations before being let go.

My general impression is that this is just about the only thing that is immediately within the power of a board to accomplish.

It is additionally the only very public way that they can look like they are "at work" on fixing it.

So I usually take it as a way to rally stock prices once they've gone down; public perception matters. The CEO is the scapegoat.

I think it also speaks to the fact that the average CEO is just that: average. Few CEOs seem to be able to repetitively arrive at a new company and increase its efficiency or profits. Also, few CEOs completely run a company in the ground. So in the end it doesn't hurt the company much and an average level replacement won't be particularly hard to find.

SchizoidSocialClubIQ, IQ never changes 2 points3 points 3 years ago

Psychiatry and psychology are going to be guesswork until mental processes are better understood, but that doesn't stop psychologists to have very strong opinions not only about what their patients should do but about what society should do.

[deleted] 5 points6 points 3 years ago

For me music is useful if I'm doing something relatively mindless, such as menial excel work, creating a PowerPoint or writing a report about something I'm familiar with. In those cases it eggs me on and helps me keep the pace of work up, which otherwise tends to grind to a halt.

For anything more complex it distracts me since I actually have to think rather than just produce.

[deleted] 4 points5 points 3 years ago

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fun-vampire 3 points4 points 3 years ago

As far as the Brazilian Jiu-jitsu questions goes, I think it's because MMA as it currently exists didn't really exist until recently. The Gracie's style isn't the best style of unarmed combat period, its' merely the best based on the rules the UFC popularized for MMA.

Similarly, ancient and medieval fencing and boxing don't look like modern fencing or boxing at all because the rules changed so much (especially the advent of thick gloves in boxing).

Aggravating_Face 6 points7 points 3 years ago

I think it's misleading to characterize the furry fandom as a fetish community. That aspect exists, but there are plenty of furries who aren't into it.

Regardless, it's still a good question.

PM_ME_UR_OBSIDIANhad a qualia once[M] 2 points3 points 3 years ago

FYI, this comment was accidentally spam-filtered. I just restored it.

[deleted] 2 points3 points 3 years ago

I hear this fairly often but (as an outsider) the only furry content I come across is sexual (except for this bizarre rage comic). I would be interested in finding out what percentage of furries don't see it as a sex thing.

k5josh 8 points9 points 3 years ago
  • Just who is Gwern?

headpatthrowaway 11 points12 points 3 years ago

newworkaccount 7 points8 points 3 years ago

That is interesting but less than enlightening. Why do they remain anonymous? DNM reporting?

Many people might desire to remain anonymous; few have such good reasons to remain anonymous that others try to extort them.

And it is an unusual person who takes these attempts and makes them a bet.

(Wise in a sense, though: now you have people with no ill will that may reveal 'bugs' in your anonymity alongside the ordinary kind of doxx that are done entirely with ill will.

I'm not convinced that's the point of it; some people just find that sort of thing fun.)

SelectivePressure 15 points16 points 3 years ago

Gwern writes about taboo topics, reports on self-administered grey market and black market drugs/nootropics, and scans and uploads texts that are not yet public domain. I can see why anonymity is beneficial in those regards.

newworkaccount 5 points6 points 3 years ago

Thanks for clarifying! Have they long been a fixture on that scene? Interesting too that non-sensitive activities are being done on the same site: generally with security you want to isolate identities to keep anything from connecting them (i.e. there are lot of computer scientists, but maybe not so many cryptographers, or bioinformatics people; niche knowledge can identify you sometimes).

[deleted] 8 points9 points 3 years ago

I know you are just playing along with "they" but I would be shocked if "he" was inappropriate.

newworkaccount 5 points6 points 3 years ago

Probably so, but since I don't think gender is a big deal and it costs me nothing to be egalitarian, I usually do so on the off chance it makes life better for someone.

gwern 0 points1 point 3 years ago

That is interesting but less than enlightening. Why do they remain anonymous? DNM reporting?

That alone would be enough. Consider Brian Krebs being subjected to repeated swattings (swattings have been fatal in the past) and conspiracies to mail him heroin. Or more recently Deku-shrub made the mistake of antagonizing DNM-related scammers and they got him raided and arrested by UK police. I'm just as happy to avoid that, and the mistaken doxes of me demonstrate people have made attempts in that direction.

It's not paranoia when they really are out to get you.

Sniffnoy 2 points3 points 3 years ago

There used to be a bit on Gwern's site about how someone once successfully identified them, but it seems to have been taken down, presumably for the obvious reason...

lehyde 4 points5 points 3 years ago

what, algorithmicly, are mathematicians doing when they do math which explains how their proofs can usually be wrong but their results usually right? Is it equivalent to a kind of tree search like MCTS or something else?

I'm pretty sure doing math is AI complete, i.e., if you solve that question you have solved general artificial intelligence.

gwern 9 points10 points 3 years ago

If you did it perfectly, sure. But we don't need to go that far. Right now we don't even know what the answer would look like.

Like, we have a reasonably good answer for "what is the visual cortex doing when you 'look' at something?" It's doing something like a really powerful multi-layer recurrent convolutional neural network. This explains the neuroimaging results, the low-level neuroanatomical details, top-down processing, we can get good (if not always human-level) performance, we can use CNNs to predict visual cortex activity, and we can even extract images from a running human brain. It's certainly not fully solved, there's a lot of generalization problems and CNNs don't match us on various kinds of distortions or fall to the same optical illusions, but in 50 years it seems safe to say that the visual cortex is still going to be modeled as some sort of CNN.

When you ask someone, "what is a mathematician's brain doing when they 'do math'?", their brow just furrows and they go, "they're doing... some... sort of... tree search... maybe?"

MinusInfinitySpoons๐Ÿ“Ž โ‹ฏ ๐Ÿ–‡ โ‹ฏ ๐Ÿ–‡๐Ÿ–‡ โ‹ฏ ๐Ÿ–‡๐Ÿ–‡๐Ÿ–‡๐Ÿ–‡ โ‹ฏ 4 points5 points 3 years ago

I think it would help clarify things to break your question up into two parts:

1) What's going on in mathematicians' brains when they're discovering theorems/proofs, and

2) Why is it that their theorems are usually correct even though their proofs often have significant gaps/errors?

One aspect of the answer to (2) is that, formally speaking, there is no logical distinction between a "theorem" and any other statement in a valid mathematical proof. Every statement in the proof should be true (modulo any contextual assumptions, e.g. if it's a proof by contradiction, then each step should be true in the sense that it was validly deduced from the hypothesis that was assumed for the sake of argument). But some statements are specially marked as "theorems" (or "lemmas" or "corollaries"), because they are especially interesting to mathematicians, which usually means they are especially useful for proving other statements (not just in the sense of being tools for further research, but also in the sense of summarizing many previously known special cases in one general statement).

So for that reason, mathematicians are much more likely to think about the implications of a statement, and notice if it contradicts any of their other mathematical beliefs, if it is specially marked as a theorem, as opposed to just being "sentence 3 of paragraph 2 of page 5" of the proof of some theorem. In a sense, it's an indication of the author's confidence in a statement, and, to the extent that it's an accurate signal, it means something like "I consider this statement especially unlikely to be erroneous, because, compared to the other statements in this text, I put extra effort into making sure I wrote this one down correctly, and thought more about whether it fits into the general pool of mathematical knowledge without causing any paradoxes." So even when the proof is flawed, that implicit endorsement constitutes some degree of empirical evidence that the theorem is true anyway.

For example, in "The Existential Risk Of Math Errors," in the excerpt you quoted from "How to Write a Proof," Leslie Lamport cited the proof of the Schrรถder-Bernstein theorem from John Kelley's General Topology as an example of a very subtle, hard to notice mistake. This piqued my interest, so I tracked down the relevant passage in Google Books (screenshot), and stared at it until I could find the mistake myself, which did indeed take a while. (Spoiler: Kelley fails to account for the case of points which are "ancestors" of themselves, i.e. the sequence generated by repeated applications of gโ—‹f (or fโ—‹g) to a point x cycles back around to x. He should have included such points in A_I (resp. B_I), but, going by his definitions, they instead end up in A_E, and get mapped by f not to B_0, as claimed, but to B_E.) I'm sure I would have missed it if I hadn't been looking for it. OTOH, seems unlikely to me that anyone would think to reuse one of the erroneous statements from Kelley's proof, unless they were closely imitating that particular proof to prove some very similar statement, whereas the Schrรถder-Bernstein theorem is useful for proving all sorts of other things, so if it were false, someone would probably notice the resulting contradictions sooner or later.

One could make an analogy to programming, whereby theorems correspond to APIs, and proofs correspond to implementations thereof. Ideally, one would like that if there's a bug in the implementation, it would be fixable without having to change the API too. Alternatively, you could analogize fixable mistakes in the mundane details of a proof to trapped errors whose damage can be contained, and theorems which are false as stated to untrapped errors that can cause data corruption or security exploits.

Anyway, that's hardly a full answer to question (2), and barely touches upon question (1). I wanted to say more, but I seem to have gotten side-tracked and now I need to go do other things. Maybe later ... In the meantime, do you know about any attempts to apply recent advances in machine learning to automated theorem proving? It sounds like your question is motivated by that problem. I've been wondering about it myself lately. Could generating proofs of nontrivial theorems in a system like Coq/HOL/etc. really be that much harder than learning to beat human experts at complex games like go and DOTA 2 entirely from self-play?

gwern 1 point2 points 3 years ago

In the meantime, do you know about any attempts to apply recent advances in machine learning to automated theorem proving? It sounds like your question is motivated by that problem. I've been wondering about it myself lately. Could generating proofs of nontrivial theorems in a system like Coq/HOL/etc. really be that much harder than learning to beat human experts at complex games like go and DOTA 2 entirely from self-play?

I can't really speak to the rest, other than to wonder how we can have priors about logical uncertainty in the first place when it seems like every form of mathematics should be possible and most theorems true or false with different axioms (I am also puzzled by the connection to Chaitin's omega and Godel's incompleteness in terms of how many simple or provable theorems there are compared to unprovable or independent/decided by fiat ones).

I have actually been thinking of mathematical proving as similar to MCTS since well before AlphaGo since it feels like it has a similar set of properties: like in chess or game-playing, human mathematicians clearly do do some limited explicit tree-style recursion, they improve gradually the longer they think about it (anytime), there's randomness and jitter in estimates (from random rollouts vs ???), they preferentially explore promising seeming avenues while occasionally checking other different approaches, and so on.

Theorem-proving has explored use of heuristics and ML-tuned heuristics for a while and they're the cutting edge of theorem-proving (using corpuses of human-written proofs and then seeing how many other known theorems can be proven in a time budget), and there have been attempts modeled after AlphaGo and I believe they are at or near SOTA, but they haven't blown the competition away (last I read one of the papers). Self-play so far hasn't been relevant since what are you playing against? It's a game against Nature/Math, not yourself. So not obvious what, if anything, you are bootstrapping or playing against, so self-play hasn't come up that I can recall. The merely SOTA performance may be related to the very poor encoding/embedding of available theorems into the NNs (frequently something like a fixed-length vector fed into a CNN or RNN) and so maybe someone using newer methods for structured data (like set or graph NNs which can operate over dynamically changing sets of theorems which are symbolically connected) will discover that that was all that was necessary for a big leap. We'll see. EDIT: example: https://arxiv.org/abs/1811.00796

In any case, MCTS is not quite right - one difference that seems salient to me is that by construction of the proof tree, it will only ever explore valid inferential steps, while humans are clearly willing to simply assume a premise for a while or even assume a premise they think is false and proceed along 'fictional' trees of inference and get an answer with an invalid proof which is still right. A theorem-proving NN would, even if the NN has learned similar 'intuitions', be forced to go 'the long way around', if you follow me. So MCTS is at best a loose metaphor for tree-like searching.

Silverset 2 points3 points 3 years ago

I would say the question does seem to hit at general intelligence, even though in principle it wouldn't necessarily have to.

The feeling of trying to "do math" is like trying to "guess" some idea that would make progress. I would argue this experience is just like an entrepreneur trying to "guess" a good business idea, a writer trying to "guess" a compelling story, a scientist trying to "guess" an elegant model that explains some observations, etc.

Silverset 1 point2 points 3 years ago

That specific question has an easy (and unenlightening) answer. The difficulty of giving an error free, formal proof of something is much higher than the difficulty of collecting enough evidence to make a correct guess.

Before you sit down to prove something, you've already convinced yourself it is true by some combination of computer experiments, checking it on a broad range of representative examples, having some compelling hueristic reason to expect it ought to be true, etc.

[deleted] 6 points7 points 3 years ago

why do humans, pets, and even lab animals of many species kept in controlled lab conditions on standardized diets appear to be increasingly obese over the 20th century? What could possibly explain all of them simultaneously becoming obese?

It's not an open question. It's been answered by Taubes, Lustig and others.

Sugar / carbs.

Most house pets are carnivores, they have a low tolerance to carbs, particularly cats. Any amount makes them type 2 diabetic.

Lab animals are fed a diet based on the failed fatphobic hypothesis. Even when they're eating carbs in the wild, they're probably fed refined carbs.

As for humans, obesity correlates perfectly with sugar intake.

brberg 13 points14 points 3 years ago

standardized diets

The claim here is that the diets aren't changing. Lab animals are being fed the exact same thing, and they're getting fatter. I don't know for a fact that this is true, but that's the claim.

[deleted] 3 points4 points 3 years ago

That's assuming the standard has remained the same over decades. In all likelihood, the standard has changed with the times.

nootandtoot 12 points13 points 3 years ago

Taubes is primarily is more writer than researcher. And there are many researchers that disagree with this like Stephen Guyenet, a very bright obesity researcher. His defense against sugar is herehttp://www.stephanguyenet.com/why-the-carbohydrate-insulin-model-of-obesity-is-probably-wrong-a-supplementary-reply-to-ebbeling-and-ludwigs-jama-article/

Also make sure not to read his article as sugar as a claim that sugar does not influence obesity. He is only arguing it is one of many factors, and probably influences obesity through palatability.

โ€‹

[deleted] -2 points-1 points 3 years ago

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[deleted] 0 points1 point 3 years ago

How can anyone take himself seriously with a name pronounced like that?

It's pretty easy actually.