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Meetup : London Social - October 26th

0 sixes_and_sevens 20 October 2014 12:20PM

Discussion article for the meetup : London Social - October 26th

WHEN: 26 October 2014 03:00:00PM (+0100)

WHERE: Holborn, London

The next London meetup will be Sunday October 26th from 2pm. No topic or special activity. Just turn up and talk about what interests you.

The venue is the Shakespeare's Head near Holborn tube station. We'll generally have some sign attesting to the group's identity, and usually try to get one of the large circular tables near the back of the pub.

About London LessWrong:

We're currently running meetups every other Sunday, and tend to get between 5 and 15 attendees. Most of our meetups default to unstructured social discussion on LessWrongy subjects, though we occasionally have special topics, events or activities. Sometimes we play games.

We have a Google Group and a Facebook group where we plan and discuss stuff. We would be extraordinarily pleased if you joined them.

Discussion article for the meetup : London Social - October 26th

Meetup : Urbana-Champaign: Meta-systems and getting things done

0 Manfred 20 October 2014 04:16AM

Discussion article for the meetup : Urbana-Champaign: Meta-systems and getting things done

WHEN: 26 October 2014 02:00:00PM (-0500)

WHERE: 206 S. Cedar St., Urbana IL

Seed topic:

When I was a little kid doing chores, what worked was for my mom to tell me to do one thing. Then I'd do the thing, and come back and ask her "what next?" And then she'd tell me another thing, and I'd do that, and so on.

A few weeks ago Brienne posted a technique that can be used to do this with a mental model of someone smart. You build a model of what an effective person would do, and you ask your model what thing to do next, and the model tells you, and then you do that. This one of many ways of reminding yourself to follow the pattern "find the best strategy, and then do the next step in that strategy."

If you desire homework: try doing this for a few hours at some point during the week.

By contrast, consider the Getting Things Done family of productivity techniques, where you write down what you want to do in advance and then follow your written plan. How well has this worked for you in the past? (As one might predict, results vary).

Discussion article for the meetup : Urbana-Champaign: Meta-systems and getting things done

New LW Meetup: Bath UK

2 FrankAdamek 19 October 2014 11:12PM

European Community Weekend 2015

16 Lachouette 19 October 2014 03:02PM

The Berlin meetup group is organizing the LessWrong Community Weekend 2015. From June 12th to 14th awesome people from all across Europe are coming to Berlin to meet, exchange ideas and start projects. The focus is on forming new and strengthening existing ties between our local communities. In addition to being a vibrant social event, it’s also about sharing your world-improvement projects as well as about teaching and learning valuable skills.

If you are already attending a local meetup, you might find this to be similar in the way it mixes a social event with workshops and talks. And if you don’t have a meetup nearby, this is a great opportunity to get in touch with the community.

Our 2014 event had an unexpectedly huge turnout. This time we have planned for a larger number of participants yet might still be underestimating the size of the community and its growth since last year. So sign up quickly if you want to be sure to get in.

Building on our experience and the feedback from the last event we are making this event even more awesome: The new location offers several seminar rooms for parallel workshops, activities and discussions in smaller groups. Combined with shorter and more efficient talks this leaves more space for structured social time and activities.

Participants are encouraged to share their knowledge in workshops, tutorials and talks as well as exchange experiences in informal settings. Featured topics include practical rationality, self improvement, world improvement and other rationality related areas.

Giving a workshop or talk is a great way to introduce yourself to other attendants and start a discussion about a topic you care about. If you're unsure if the topic is valuable or a good fit, please err on the side of including it! The more content offers we get, the easier it will be to create a balanced, yet diverse program.

Next to the talks, there is plenty of opportunity to get to know your fellow participants better in structured and less structured social settings. The chosen location provides many opportunities to spend off-time outside, whether you'd rather take a few companions on a morning hike in the nearby forest while discussing AI, receive a tutorial in proper stone-skipping technique at lake Wannsee or if you'd prefer a game of ultimate frisbee on the premises. Which specific activities will be offered during the weekend depends on the participants themselves, so make sure to tell us on the signup form if there's a skill you can share or an activity you'd like to offer.

The event begins on Friday June 12th, 12:00 with our shared lunch. Then we will move to our main location, Jugendherberge Berlin-Am Wannsee that provides us with seminar rooms and on-site accommodation (shared rooms, 4 beds) as well as access to the nearby lake and forest. The next days will be filled with workshops, talks, discussions and many other activities. We’ll say goodbye on Sunday June 14th at 15:00.

Costs are €150 including accommodation for two nights, the welcome reception and lunch on Friday and all the other meals till lunch on Sunday.

You can sign up for the event now. If you sign up early, you are guaranteed to get a spot, so don't delay it too much if you're interested!

The European LW community is pretty scattered at the moment. This event is our chance to reach out and build lasting bonds and friendships across cities and borders. Are you looking for allies for your world-optimization plans, or for new methods to improve yourself and your model of the world? Do you want to teach others what you have learned? Or are you looking forward to a relaxing weekend around like-minded people?
The community weekend can offer all those things and more, and you can help make it the event that you want it to be!

Looking forward to seeing you
Alexander, Anne, Christian, John, Marcel, Matthias and Tristan


P.S.: If you have any questions about the event you can reach us at lwcw2015@gmail.com.

Applications of logical uncertainty

11 alex_zag_al 18 October 2014 07:26PM

Lately I've been reading a lot about the problem of logical uncertainty. The problem is that there are logical consequences of your beliefs that you're uncertain about.

So, for statements like "the billionth digit of pi is even", it's provable from your beliefs. But you're still uncertain of it. So, the problem is, what's its probability? Well, 1/2, probably, but from what principled theory can you derive that?

That's the question. What probabilities we should assign to logical statements, and what laws of probability apply to them.

With all the time I've been spending on it, I've been wondering, will I ever have the opportunity to use it? My conclusion is, probably not me, personally. But I have come up with a decent list of ways other people might use it.

Combining information from simulation and experiment

This is why I first became interested in the problem--I was working in protein structure prediction.

The problem in protein structure prediction is figuring out how the protein folds. A protein is a big molecule. They're always these long, linear chains of atoms with relatively short side-branches. Interestingly, there are easy experiments to learn what they'd look like all stretched out in a line like this. But in reality, this long chain is folded up in a complex way. So, the problem is: given the linear, stretched out structure, what's the folded structure?

We have two general approaches to solve this problem.

One is a physics calculation. A protein folds because of electromagnetic forces, and we know how those work. So, you can set up a quantum physics simulation and end up with the correct fold. But you won't really end up with anything because your simulation will never finish if you do it precisely. So a lot of work goes into coming up with realistic approximate calculations, and using bigger computers. (Or distributed computing - Rosetta@Home distributes the calculations over the idle time of people's home computers, and you can download it now if you want your computer to help solve protein structures.)

Another is by experiment. We get some kind of reading from the protein structure--X-rays or radio waves, usually--and use that to solve the structure. This can be thought of as Bayesian inference, and, in fact, that's how some people do it--see a book dear to my heart, Bayesian Methods in Structural Bioinformatics. Some of the chapters are about P(observations|structure), and some are about the prior distribution, P(structure). This prior usually comes from experience with previous protein structures.

(A third approach that doesn't really fit into this picture is the videogame FoldIt.)

But, it occurred to me, doesn't the simulation provide a prior?

This is actually a classic case of logical uncertainty. Our beliefs actually imply a fold--we know the linear chain, we know the laws of physics, from that you can theoretically calculate the folded structure. But we can't actually do it, which is why we need experiments, the experiments are actually resolving logical uncertainty.

My dream is for us to be able to do that explicitly, in the math. To calculate a prior using the laws of physics plus logical uncertainty, and then condition on experimental evidence to resolve that uncertainty.

There are two people that I know of, doing research that resembles this. One is Francesco Stingo. He published a method for detecting binding between two different kinds of molecules--miRNA and mRNA. His method has a prior that is based in part on chemistry-based predictions of binding, and updated on the results of microarray experiments. The other is Cari Kaufman, who builds probability distributions over the results of a climate simulation. (the idea seems to be to extrapolate from simulations actually run with similar but not identical parameters)

What I have in mind would accomplish the same kind of thing in a different way--the prior would come from a general theory for assigning probabilities to statements of mathematics, and "the laws of physics predict these two molecules bind" would be one such statement.

Automated theorem proving

I don't know anything about this field, but this kind of makes sense--what if you could decide which lemmas to try and prove based on their probability? That'd be cool.

Or, decide which lemmas are important with value of information calculations.

(AlanCrowe talked about something like this in a comment)

Friendly AI

I don't really understand this, something about a "Löbian obstacle." But Squark has a bit of an overview at "Overcoming the Loebian obstacle using evidence logic". And qmaurmann wrote something on a similar topic, "Meditations on Löb’s theorem and probabilistic logic." eli_sennesh also recently wrote a related post.

There's an interesting result, in this line of research. It says that, although it's well known that a formal system cannot contain a predicate representing truth in that system, this is actually just because formal proof systems only assign certainties of 0 and 1. If they instead gave false statements probability infinitesimally close to 0, and true statements infinitesimally close to 1, they could define truth. (Disclaimer: I can't follow all the math and the result has not yet been published in a peer reviewed journal). This is such an odd use of probabilistic logical uncertainty, nothing like the applications I've been imagining, but there it is.

(walkthrough of the paper here)


Philosophically, I want to know how you calculate the rational degree of belief in every proposition. Good philosophical theories don't necessarily need to be practical to use. Even if it's impossible to compute, it's got to give the right answer in simple thought experiments, so I feel like I can reason without paradox. But even getting all these simple thought experiments right is hard. Good philosophical theories are hard to come by.

Bayesian confirmation theory has been a successful philosophical theory for thought experiments involving the confirmation of theories by evidence. It tells you how belief in a hypothesis should go up or down after seeing observational evidence.

But what about mathematical evidence, what about derivations? Wasn't Einstein's derivation that general relativity predicts the orbit of Mercury evidence in favor of the theory? I want a philosophical theory, I want basic principles, that will tell me "yes." That will tell me the rational degree of belief is higher if I know the derivation.

Philosophers frame this as the "problem of old evidence." They think of it like: you come up with a new theory like GR, consider old evidence like Mercury, and somehow increase your confidence in the new theory. The "paradox" is that you didn't learn of any new evidence, but your confidence in the theory still changed. Philosopher Daniel Garber argues that the new evidence is a mathematical derivation, and the problem would be solved by extending Bayesian probability theory to logical uncertainty. (The paper is called "Old Evidence and Logical Omniscience in Bayesian Confirmation Theory," and can be found here)

A more general philosophical theory than Bayesian confirmation theory is Solomonoff induction, which provides a way to assign probabilities to any observation given any past observations. It requires infinite computing power. However, there still is a rational degree of belief for an agent with finite computing power to have, given the computations that they've done. I want the complete philosophical theory that tells me that.

Learning about probabilistic logical uncertainty

I made a list of references here, if you'd like to learn more about the subject.

Meetup : Perth, Australia: Discussion: How to be happy

1 ab9 18 October 2014 09:23AM

Discussion article for the meetup : Perth, Australia: Discussion: How to be happy

WHEN: 04 November 2014 06:00:00PM (+0800)

WHERE: Sync Labs, 6/663 Newcastle Street, Leederville, Australia

Happiness is pretty great, and fortunately there's scientific research on the subject. lukeprog read a lot of this research and summarised it in How to Be Happy.

Come make some tea and discuss the article! We'll raise questions like:

  • What's important for happiness? What isn't? (Spoiler: money isn't, once you're over the poverty line.)
  • Do any of lukeprog's conclusions seem wrong? Do any seem surprising?
  • Have you ever done any of the things lukeprog recommends for becoming happier – such as becoming more extroverted, or switching to more fulfilling work? What effect did it have on your happiness?

You can RSVP here: http://www.meetup.com/Perth-Less-Wrong/events/214179922/

The entrance to Sync Labs is between Cranked and Niche. Don't trust Google Maps!

Discussion article for the meetup : Perth, Australia: Discussion: How to be happy

Meetup : Washington D.C. - Mini Talks

1 RobinZ 17 October 2014 07:16PM

Discussion article for the meetup : Washington D.C. - Mini Talks

WHEN: 19 October 2014 03:00:00PM (-0400)

WHERE: National Portrait Gallery

We will be meeting in the Kogod Courtyard of the National Portrait Gallery (8th and F Sts or 8th and G Sts NW, go straight past the information desk from either entrance) to take turns presenting ~10-20 minute lectures on random topics. As usual, we will congregate between 3:00 to 3:30, begin giving talks at 3:30, and continue as long as people are interested or until closing, whichever comes first.

If you need to show up late or leave early, that's fine. Let us know if you want to take a turn behind the notional podium before/at/after a specific time, or if there are any special materials you want to have.

Upcoming meetups:

  • Oct. 26: Create & Complete (bring projects, get help and social support as you work on them)
  • Nov. 2: Fun & Games (bring games, play games, converse, socialize, or any combination thereof)
  • Nov. 9: To Be Announced (to be summarized)

Discussion article for the meetup : Washington D.C. - Mini Talks

Crossing the History-Lessons Threshold

26 lionhearted 17 October 2014 12:17AM


Around 2009, I embarked on being a serious amateur historian. I wouldn't have called it that at the time, but since then, I've basically nonstop studied various histories.

The payoffs of history come slow at first, and then fast. History is often written as a series of isolated events, and events are rarely put in total context. You can easily draw a straight line from Napoleon's invasions of the fragmented German principalities to how Bismarck and Moltke were able to unify a German Confederation under Prussian rule a few decades later; from there, it's a straight line to World War I due to great power rivalry; the Treaty of Versailles is easily understood in retrospect by historical French/German enmity; this gives rise to World War II.

That series of events is hard enough to truly get one's mind around, not just in abstract academic terms, but in actually getting a feel of how and why the actors did what they did, which shaped the outcomes that built the world.

And that's only the start of it: once you can flesh out the rest of the map, history starts coming brilliantly alive.

Without Prime Minister Stolypin's assassination in 1911, likely the Bolsheviks don't succeed in Russia; without that, Stalin is not at the helm when the Nazis invade. 

On the other side of the Black Sea, in 1918, the Ottoman Empire is having terms worse than the Treaty of Versailles imposed on it -- until Mustafa Kemal leads the Turkish War of Independence, building one of the most stable states in the Middle East. Turkey, following Kemal's skill at governance and diplomacy, is able to (with great difficulty) stay neutral in World War II, not be absorbed by the Soviets, and not have its government taken over by hard-line Muslims.

This was not-at-all an obvious course of events. Without Kemal, Turkey almost certainly becomes crippled under the Treaty of Sevres, and eventually likely winds up as a member of the Axis during World War II, or gets absorbed as another Soviet/Warsaw Pact satellite state.

The chain of events goes on and on. There is an eminently clear chain of events from Martin Luther at Worms in 1521 to the American Revolution. Meanwhile, the non-success the Lord Protectorate and Commonwealth of England turned out less promising than was hoped -- ironically, arguably predisposing England to being less sympathetic to greater democracy. But the colonies were shielded from this, and their original constitutions and charters were never amended in the now-becoming-more-disenchanted-with-democracy England. Following a lack of consistent colonial policy and a lot of vacillating by various British governments, the American Revolution happens, and Britain loses control of the land and people would come to supplant it as the dominant world power one and a half centuries later.


Until you can start seeing the threads and chains of history across nations, interactions, and long stretches of time, history is a set of often-interesting stories -- but the larger picture remains blurry and out-of-focus. The lessons come once you can synthesize it all.

Hideyoshi Toyotomi's 1588 sword hunt was designed to take away weapons and chances of rebellious factions overthrowing his unified government of Japan. The policy was continued by his successor after the Toyotomi/Tokugawa Civil War, which leads to the Tokugawa forces losing to the Imperial Restoration in 1868 as their skill at warfare had atrophied; common soldiers with Western artillery were able to out-combat samurai with obsolete weapons.

Nurhaci founded the Qing Dynasty around the time Japan was being unified, with a mix of better command structures and tactics. But the dynasty hardened into traditionalism and was backwards-looking when Western technology and imperialists came with greater frequency in the late 1800's. The Japanese foreign minister Ito Hirobumi offered to help the Qing modernize along the lines Imperial Japan had modernized while looking for a greater alliance with the Chinese. But, Empress Dowager Cixi arrests and executes the reform-minded ministers of Emperor Guangxu and later, most likely, poisoned the reform-minded Emperor Guangxu. (He died of arsenic poisoning when Cixi was on her deathbed; someone poisoned him; Cixi or someone acting under her orders is the most likely culprit.)

The weak Qing Dynasty starts dealing with ever-more-frequent invasions, diplomatic extortions, and rebellions and revolutions. The Japanese invade China a generation after Hirobumi was rebuffed, and the Qing Dynasty entirely falls apart. After the Japanese unconditional surrender, the Chinese Civil War starts; the Communists win. 


From this, we can start drawing lessons and tracing histories, seeing patterns. We start to see how things could have broken differently. Perhaps Germany and France were doomed to constant warfare due to geopolitics; maybe this is true.

But certainly, it's not at all obvious that Mustafa Kemal would lead the ruins of the Ottoman Empire into modern Turkey, and (seemingly against overwhelming odds) keep neutrality during World War II, rebuff Stalin and stay removed from Soviet conquest, and maintain a country with secular and modern laws that honors Muslim culture without giving way to warlordism as happened to much of the rest of the Middle East.

Likewise, we can clearly see how the policies of Empress Dowager Cixi ended the chance for a pan-East-Asian alliance, trade bloc, or federation; it's not inconceivable to imagine a world today were China and Japan are incredibly close allies, and much of the world's centers of commerce, finance, and power are consolidated in a Tokyo-Beijing-Seoul alliance. Sure, it's inconceivable with hindsight, but Japan in 1910 and Japan in 1930 are very different countries; and the struggling late Qing Dynasty is different than the fledgling competing factions in China after the fall of the Qing.

We can see, observing historical events from broad strokes, the huge differences individuals can make at leveraged points, the eventual outcomes in Turkey and East Asia were not-at-all foreordained by geography, demographics, or trends.


Originally, I was sketching out some of these trends of history to make a larger point about how modern minds have a hard time understanding older governments -- in a world where "personal rule" is entirely rebuffed in the more developed countries, it is hard to imagine how the Qing Dynasty or Ottoman Empire actually functioned. The world after the Treaty of Westphalia is incredibly different than the world before it, and the world before strict border controls pre-WWI is largely unrecognizable to us.

That was the piece I was going to write, about how we project modern institutions and understandings backwards, and how that means we can't understand what actually happened. The Ottomans and Qing were founded before modern nationalism had emerged, and the way their subjects related to them is so alien to us that it's almost impossible to conceive of how their culture and governance actually ran.


I might still pen that piece, if there's interest in it -- my attempt at a brief introduction came to result in this very different one, focused on a different particular point: the threshold effect in learning history.

I would say there's broadly three thresholds:

The first looks at a series of isolated events. You wind up with some witty quips, like: Astor saying, "Sir, if you were my husband, I would poison your drink." Churchill: "If I were married to you, I'd drink it." 

Or moments of great drama: "And so the die is cast." "Don't fire until you see the whites of their eyes." "There is nothing to fear except fear itself."

These aren't so bad to learn; they're an okay jumping-off place. Certainly, Caesar's decision to march on Rome, Nobunaga's speech before the Battle of Okehazama, or understanding why Washington made the desperate gamble to cross the Delaware all offerlessons.

But seeing how the Marian military reforms, Sulla's purges, and the Gracchi brothers created the immediate situation before Julius Caesar's fateful crossing is more interesting, and tracing the lines backwards, seeing how Rome's generations-long combat with Hannibal's Carthage turned the city-state into a fully militarized conquest machine, and then following the lines onwards to see how the Romans relied on unit cohesion which, once learned by German adversaries, led to the fall of Rome -- this is much more interesting. 

That's the second threshold of history to me: when isolated events start becoming regional chains; that's tracing Napoleon's invasion of Germany to Bismarck to the to World War I to the Treaty of Versailles to WWII.

Some people get to this level of history, and it makes you quickly an expert in a particular country.

But I think that's a poor place to stop learning: if you can truly get your mind around a long stretch of time in a nation, it's time to start coloring the map. When you can broadly know how Korea is developing simultaneous with Japan; how the Portugese/Spanish rivalry and Vatican compromises are affecting Asia's interactions with the Age of Sail Westerners; how Protestantism is creating rivals to Catholic power, two of which later equip the Japanese's Imperial Faction, which kicks off the Asian side of World War II -- this is when history starts really paying dividends and teaching worthwhile lessons.

The more you get into it, the more there is to learn. Regions that don't get much historical interest from Americans like Tito's Yugoslavia become fascinating to look at how they stayed out of Soviet Control and played the Western and Eastern blocs against each other; the chain of events takes a sad turn when Tito's successors can't keep the country together, the Yugoslav Wars follow, and its successor states still don't have the levels of relative prosperity and influence that Yugoslavia had in its heyday. 

Yugoslavia is hard to get one's mind around by itself, but it's easy to color the map in with a decent understanding of Turkey, Germany, and Russia. Suddenly, figures and policies and conflicts and economics and culture start coming alive; lessons and patterns are everywhere.

I don't read much fiction any more, because most fiction can't compete with the sheer weight, drama, and insightfulness of history. Apparently some Kuomintang soldiers held out against the Chinese Communists and fought irregular warfare while funding their conflicts with heroin production in the regions of Burma and Thailand -- I just got a book on it, further coloring in the map of the aftermath of the Chinese Civil War, and that aspect of it upon the backdrop of the Cold War and containment, and how the Sino/Soviet split led to America normalizing relations with China, and...

...it never ends, and it's been one of the most insightful areas of study across my life.

History in that first threshold -- isolated battles, quotes, the occasional drama -- frankly, it offers only a slight glimmer of what's possible to learn.

Likewise, the second level of knowing a particular country's rise and fall over time can be insightful, but I would encourage anyone that has delved into history that much to not stop there: you're not far from the gates unlocking to large wellsprings of knowledge, a nearly infinite source of ideas, inspiration, case studies, and all manner of other sources of new and old ideas and very practical guidance.

Meetup : Urbana-Champaign: Stoicism, anthropics

0 Manfred 16 October 2014 01:21PM

Discussion article for the meetup : Urbana-Champaign: Stoicism, anthropics

WHEN: 19 October 2014 02:00:00PM (-0500)

WHERE: 206 S Cedar St, Urbana IL

If you want to read up on Stoicism, check out the encyclopedia of philosophy entry.

For anthropics, see a recent discussion here.

Discussion article for the meetup : Urbana-Champaign: Stoicism, anthropics

Meetup : **MelbLW: October Social Meetup**

2 MelbourneLW 15 October 2014 10:44PM

Discussion article for the meetup : **MelbLW: October Social Meetup**

WHEN: 17 October 2014 06:30:00PM (+0800)

WHERE: Alchemist's Refuge, 328 Little Lonsdale St, Melbourne

October's social meetup is scheduled for this Friday (17th October) as usual. This month, we will be returning to Alchemist's Refuge. Our social meetups are relaxed, informal events where we chat and often play games. The start and finish times are very loose - people will be coming and going throughout the night, so don't worry if you are coming later or have to leave early.

Where? Alchemist's Refuge, 328 Little Lonsdale St, Melbourne - near the corner of Queen St, downstairs from Games Laboratory (note: last month's announcement incorrectly listed the address as Lt Collins St, don't be fooled!)

When? From 6:30pm until late, Friday October 17th

Contact? If you have any questions, just text or call Richard on 0421231789

Dinner? There are a number of take-away places nearby that deliver to Alchemist's Refuge. It is also quite likely that a group of us will go to Stalactites for late night souvlakis after Refuge closes at about 11pm.

Games? Alchemist's Refuge do allow board games and they also have a number that can be borrowed for a minor fee. Ask around and you'll easily find some others to join you!

To organise similar events, please send an email to melbournelw@gmail.com

Discussion article for the meetup : **MelbLW: October Social Meetup**

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