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A List of Open Questions

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Re: A List of Open Questions

#51

Post by zerogvt »

alasdair_ wrote: post #33

>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? I suspect the most ob…

Millions of years? That's an exaggeration. We've been around for much less: https://en.wikipedia.org/wiki/Timeline_of_human_evolution

Re: A List of Open Questions

#52

Post by abdullahkhalids »

lostdog wrote: post #48
nafey wrote: post #45

Earlier quoted context omitted.

Whats the minimal change in the rules that will bring a striking based martial art to the top?

Allow kicking or kneeing someone in the face when they're down?

I am not sure if such is allowed in another martial arts league. But from my experience in fighting, kicking someone anywhere on the body while they are on the ground will quickly and inevitably result in serious injuries. Standing up, you can "elastically catch" the kick and reduce the damage it does. On the floor, you will absorb the full force.

Re: A List of Open Questions

#53

Post by abdullahkhalids »

nafey wrote: post #45
cetico wrote: post #40

Earlier quoted context omitted.

MMA is new, historically speaking. BJJ is the best fighting style that fits the rules of MMA. Change the rules a bit and a different style will work better.

Whats the minimal change in the rules that will bring a striking based martial art to the top?

I would guess, the following rule changes will help a lot.

* Increase the minimum size of the wrist padding and gloves. Which makes it much safer to throw punches. Additionally, the design of the gloves can be regulated so grabbing someone is harder than it is now.

* Perhaps, add rules about how long you can stay on top of someone on the ground without doing significant damage. A lot of matches end up with a takedown at the start of a round followed by 3 minutes of light pounding and no serious attempt/success at a submission hold. A 20-30 second limit on no serious on the ground action will go a long way.

* Finally, we can directly change the judging criteria to make it easier to win rounds via striking dominance instead of grappling.

Re: A List of Open Questions

#54

Post by tomhoward »

lmm wrote: post #37
ALittleLight wrote: post #25

Earlier quoted context omitted.

Why is there more honor in beating someone while standing? The reason to include wrestling is that it makes the contest more closely approximate a real fight. In a real fight your opponent does have the option to go to the ground.

Depends what you consider a "real fight". E.g. I remember a Taekwando instructor saying that BJJ would always beat Taekwando in a UFC match, but he'd never want to rely on their techniques in a bar fight where there might be broken glass on the floor.

I think they mean a more traditional "real fight" - in ancient/prehistoric times, on soil or sand rather than concrete with broken glass.

Re: A List of Open Questions

#56

Post by glastra »

gnulinux wrote: post #34
craftyguy wrote: post #7

> 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? Because diet is only part of the equation. The other major factor being exercise/physical activity (and probably some genetics). If you eat 'well' but sit at a desk all day, calo…

I personally believe carbs are mostly to blame (as opposed to fats and protein). In the Western world there is this idea that fats are bad, carbs are good but somehow this idea coincidences with astronomic increase in obesity. We load everything with high-fructose corn syrup and kick fats out of our diet. There is not much research behind this and my claims aren't evidence based either. I'm more than happy to refuted…

Definitely. I don't understand why you're getting down-voted without actual refutals. I guess it generates some internal/psychological discomfort, but I expected better of HN readers.

Indeed, the only animals suffering from obesity and modern civilisation diseases (diabetes, cardiovascular disease, Alzheimer's and other degenerative or systemic diseases) are humans and those animals of other species unfortunate enough to be fed by humans.

Diet composition is obviously to blame, but not just carbohydrates (be them complex or simple, refined or "natural"). Omega-6 polyunsaturated fatty acids (and especially their ratio to omega-3's) in the diet lead to inflammatory responses throughout the body, which can, and do, wreak havoc on health.

If you look at trends in modern nutrition, carbohydrate and omega-6 consumption are at their highest and have sky-rocketed in the past 60-70 years, as have rates of prevalence for various diseases. Of course, correlation is not causation, but many studies are coming out in the recent years showing the mechanisms through which all of this takes place.

Re: A List of Open Questions

#57

Post by matt-attack »

gnulinux wrote: post #34
craftyguy wrote: post #7

> 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? Because diet is only part of the equation. The other major factor being exercise/physical activity (and probably some genetics). If you eat 'well' but sit at a desk all day, calo…

I personally believe carbs are mostly to blame (as opposed to fats and protein). In the Western world there is this idea that fats are bad, carbs are good but somehow this idea coincidences with astronomic increase in obesity. We load everything with high-fructose corn syrup and kick fats out of our diet. There is not much research behind this and my claims aren't evidence based either. I'm more than happy to refuted…

But bread had been a staple diet for quite some time. On London in the 19th century it was heavily regulated even to the point of how big a loaf of bread must be. It was literally the main diet for the working class.

Re: A List of Open Questions

#58

Post by matt-attack »

throwawaymath wrote: post #39
rprenger wrote: post #36

Earlier quoted context omitted.

The more interesting question from an economics point of view is why does anyone bother voting. Since races almost never come down to one vote, your vote almost certainly doesn't matter. Nevermind the fact that more people voted for democrats for the senate and the presidency and still lost both. The latest theory I've heard for why people vote is that being seen as a team player has social value. https://eml.berkele…

From a mathematical perspective it's pretty silly to claim your vote doesn't matter just because it's not the tie breaking vote. You should give this a read: https://www.skishore.me/voting.html . Frankly this viewpoint has always puzzled me. Your specific claim that a vote almost certainly doesn't matter because elections don't come down to a single vote seems...unsupported, to put it politely. It might be more intui…

Bit logically where was he wrong? It seems like a bit of a paradox to me. You keep say it’s wrong but can you point out exactly where his reasoning is wrong? My vote yesterday simply didn’t change any of the outcomes. That is a fact. None of the races were won by a single vote.

Re: A List of Open Questions

#59

Post by garmaine »

> 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?

This one is easy. Because Gracie jujutsu (spell it right please) with its emphasis on ground technique is only effective when you are unarmored and your opponent is unwilling to use lethal force. In military and/or life and death situations it is a good way to get yourself killed by a trained opponent. It’s not surprising at all that Gracie/Brazilian jujutsu only developed after the popularization of MMA like sporting competitions with rules that the Gracie brothers learned to exploit.

Re: A List of Open Questions

#60

Post by danieltillett »

> Why do humans have such a large mutation load on common genetic variants?

This one is answerable. Two reasons.

1. The human population is not in Hardy-Weinberg equilibrium since it has expanded so much in the recent human past (agricultural revolution and all that).

2. The human population over the last 10,000 years has experienced very strong natural selection that has carried a lot of deleterious mutations along for the ride.

What is more interesting is why we have so many chromosomal abnormalities - humans have something like 100x the rate of chromosomal abnormalities as other species.

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