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31 Vaniver 08 April 2015 02:56AM


This is a section-by-section summary and review of Sapiens: A Brief History of Humankind by Yuval Noah Harari. It's come up on Less Wrong before in the context of Death is Optional, a conversation the author had with Daniel Kahneman about the book, and seems like an accessible introduction to many of the concepts underlying the LW perspective on history and the future. Anyone who's thought about Moloch will find many of the same issues discussed here, and so I'll scatter links to Yvain throughout. I'll discuss several of the points that I thought were interesting and novel, or at least had a novel perspective and good presentation.

A history as expansive as this one necessarily involves operating on higher levels of abstraction. The first section expresses this concisely enough to quote in full:

About 13.5 billion years ago, matter, energy, time and space came into being in what is known as the Big Bang. The story of these fundamental features of our universe is called physics.

About 300,000 years after their appearance, matter and energy started to coalesce into complex structures, called atoms, which then combined into molecules. The story of atoms, molecules and their interactions is called chemistry.

About 3.8. billion years ago, on a planet called Earth, certain molecules combined to form particularly large and intricate structures called organisms. The story of organisms is called biology.

About 70,000 years ago, organisms belonging to the species Homo sapiens started to form even more elaborate structures called cultures. The subsequent development of these human cultures is called history.

Three important revolutions shaped the course of history: the Cognitive Revolution kick-started history about 70,000 years ago. The Agricultural Revolution sped it up about 12,000 years ago. The Scientific Revolution, which got under way only 500 years ago, may well end history and start something completely different. This book tells the story of how these three revolutions have affected humans and their fellow organisms.

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Crossing the History-Lessons Threshold

34 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.

A History of Bayes' Theorem

53 lukeprog 29 August 2011 07:04AM

Sometime during the 1740s, the Reverend Thomas Bayes made the ingenious discovery that bears his name but then mysteriously abandoned it. It was rediscovered independently by a different and far more renowned man, Pierre Simon Laplace, who gave it its modern mathematical form and scientific application — and then moved on to other methods. Although Bayes’ rule drew the attention of the greatest statisticians of the twentieth century, some of them vilified both the method and its adherents, crushed it, and declared it dead. Yet at the same time, it solved practical questions that were unanswerable by any other means: the defenders of Captain Dreyfus used it to demonstrate his innocence; insurance actuaries used it to set rates; Alan Turing used it to decode the German Enigma cipher and arguably save the Allies from losing the Second World War; the U.S. Navy used it to search for a missing H-bomb and to locate Soviet subs; RAND Corporation used it to assess the likelihood of a nuclear accident; and Harvard and Chicago researchers used it to verify the authorship of the Federalist Papers. In discovering its value for science, many supporters underwent a near-religious conversion yet had to conceal their use of Bayes’ rule and pretend they employed something else. It was not until the twenty-first century that the method lost its stigma and was widely and enthusiastically embraced.

So begins Sharon McGrayne's fun new book, The Theory That Would Not Die, a popular history of Bayes' Theorem. Instead of reviewing the book, I'll summarize some of its content below. I skip the details and many great stories from the book, for example the (Bayesian) search for a lost submarine that inspired Hunt for Red October. Also see McGrayne's Google Talk here. She will be speaking at the upcoming Singularity Summit, too, which you can register for here (price goes up after August 31st).

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Faith and theory

7 PhilGoetz 26 March 2011 10:26PM


Faith is often described as belief without evidence.  The famous definition in Hebrews, in its best-known form, is close to that:

"Now faith is the substance of things hoped for, the evidence of things not seen." - Hebrews 11:1 (King James Version), often attributed to St. Paul

This is the way the term "faith" is used by religious people when they argue against the primacy of reason, as demonstrated in these quotes, which is the context I am concerned with.  (It's also the meaning used by atheists arguing against religious faith, eg. Sam Harris in The End of Faith.)  But the New International Version, which is less pretty, but translated more carefully by better scholars from more and older texts, says:

"Now faith is confidence in what we hope for and assurance about what we do not see."

The Wikipedia and Plato entries on faith give information on the use of words translated as "faith" in English in different religions and philosophies.  Wikipedia cites the New American standard exhaustive concordance of the Bible as saying,

In English translations of the New Testament, the word faith generally corresponds to the Greek noun πίστις (pistis) or the Greek verb πιστεύω (pisteuo), meaning "to trust, to have confidence, faithfulness, to be reliable, to assure".[22]


Scientific theory is also assurance about things unseen.  (If you can observe something directly, you don't need science.)  Science builds an abstract mental structure that interprets data and makes predictions from it.  It is also an epistemology for belief in things we can't see, like atoms, oxygen, radio waves, vast distances, or circulation of the blood.

The history of faith and theory

The most popular belief appears to be that faith is ancient, and scientific theory came along later to supersede it.  But I'm not aware of evidence for this.

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Yes, a blog.

88 Academian 19 November 2010 01:53AM

When I recommend LessWrong to people, their gut reaction is usually "What? You think the best existing philosophical treatise on rationality is a blog?"

Well, yes, at the moment I do.

"But why is it not an ancient philosophical manuscript written by a single Very Special Person with no access to the massive knowledge the human race has accumulated over the last 100 years?"

Besides the obvious? Three reasons: idea selection, critical mass, and helpful standards for collaboration and debate.

Idea selection.

Ancient people came up with some amazing ideas, like how to make fire, tools, and languages. Those ideas have stuck around, and become integrated in our daily lives to the point where they barely seem like knowledge anymore. The great thing is that we don't have to read ancient cave writings to be reminded that fire can keep us warm; we simply haven't forgotten. That's why more people agree that fire can heat your home than on how the universe began.

Classical philosophers like Hume came up with some great ideas, too, especially considering that they had no access to modern scientific knowledge. But you don't have to spend thousands of hours reading through their flawed or now-uninteresting writings to find their few truly inspiring ideas, because their best ideas have become modern scientific knowledge. You don't need to read Hume to know about empiricism, because we simply haven't forgotten it... that's what science is now. You don't have to read Kant to think abstractly about Time; thinking about "timelines" is practically built into our language nowadays.

See, society works like a great sieve that remembers good ideas, and forgets some of the bad ones. Plenty of bad ideas stick around because they're viral (self-propagating for reasons other than helpfulness/verifiability), so you can't always trust an idea just because it's old. But that's how any sieve works: it narrows your search. It keeps the stuff you want, and throws away some of the bad stuff so you don't have to look at it.

LessWrong itself is an update patch for philosophy to fix compatibility issues with science and render it more useful. That it would exist now rather than much earlier is no coincidence: right now, it's the gold at the bottom of the pan, because it's taking the idea filtering process to a whole new level. Here's a rough timeline of how LessWrong happened:

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Why safety is not safe

48 rwallace 14 June 2009 05:20AM

June 14, 3009

Twilight still hung in the sky, yet the Pole Star was visible above the trees, for it was a perfect cloudless evening.

"We can stop here for a few minutes," remarked the librarian as he fumbled to light the lamp. "There's a stream just ahead."

The driver grunted assent as he pulled the cart to a halt and unhitched the thirsty horse to drink its fill.

It was said that in the Age of Legends, there had been horseless carriages that drank the black blood of the earth, long since drained dry. But then, it was said that in the Age of Legends, men had flown to the moon on a pillar of fire. Who took such stories seriously?

The librarian did. In his visit to the University archive, he had studied the crumbling pages of a rare book in Old English, itself a copy a mere few centuries old, of a text from the Age of Legends itself; a book that laid out a generation's hopes and dreams, of building cities in the sky, of setting sail for the very stars. Something had gone wrong - but what? That civilization's capabilities had been so far beyond those of his own people. Its destruction should have taken a global apocalypse of the kind that would leave unmistakable record both historical and archaeological, and yet there was no trace. Nobody had anything better than mutually contradictory guesses as to what had happened. The librarian intended to discover the truth.

Forty years later he died in bed, his question still unanswered.

The earth continued to circle its parent star, whose increasing energy output could no longer be compensated by falling atmospheric carbon dioxide concentration. Glaciers advanced, then retreated for the last time; as life struggled to adapt to changing conditions, the ecosystems of yesteryear were replaced by others new and strange - and impoverished. All the while, the environment drifted further from that which had given rise to Homo sapiens, and in due course one more species joined the billions-long roll of the dead. For what was by some standards a little while, eyes still looked up at the lifeless stars, but there were no more minds to wonder what might have been.

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A Parable On Obsolete Ideologies

113 Yvain 13 May 2009 10:51PM

Followup to:  Yudkowsky and Frank on Religious Experience, Yudkowksy and Frank On Religious Experience Pt 2
With sincere apologies to: Mike Godwin

You are General Eisenhower. It is 1945. The Allies have just triumphantly liberated Berlin. As the remaining leaders of the old regime are being tried and executed, it begins to become apparent just how vile and despicable the Third Reich truly was.

In the midst of the chaos, a group of German leaders come to you with a proposal. Nazism, they admit, was completely wrong. Its racist ideology was false and its consequences were horrific. However, in the bleak poverty of post-war Germany, people need to keep united somehow. They need something to believe in. And a whole generation of them have been raised on Nazi ideology and symbolism. Why not take advantage of the national unity Nazism provides while discarding all the racist baggage? "Make it so," you say.

The swastikas hanging from every boulevard stay up, but now they represent "traditional values" and even "peace". Big pictures of Hitler still hang in every government office, not because Hitler was right about racial purity, but because he represents the desire for spiritual purity inside all of us, and the desire to create a better society by any means necessary. It's still acceptable to shout "KILL ALL THE JEWS AND GYPSIES AND HOMOSEXUALS!" in public places, but only because everyone realizes that Hitler meant "Jews" as a metaphor for "greed", "gypsies" as a metaphor for "superstition", and "homosexuals" as a metaphor for "lust", and so what he really meant is that you need to kill the greed, lust, and superstition in your own heart. Good Nazis love real, physical Jews! Some Jews even choose to join the Party, inspired by their principled stand against spiritual evil.

The Hitler Youth remains, but it's become more or less a German version of the Boy Scouts. The Party infrastructure remains, but only as a group of spiritual advisors helping people fight the untermenschen in their own soul. They suggest that, during times of trouble, people look to Mein Kampf for inspiration. If they open to a sentence like "The Aryan race shall conquer all in its path", then they can interpret "the Aryan race" to mean "righteous people", and the sentence is really just saying that good people can do anything if they set their minds to it. Isn't that lovely?

Soon, "Nazi" comes to just be a synonym for "good person". If anyone's not a member of the Nazi Party, everyone immediately becomes suspicious. Why is she against exterminating greed, lust, and superstition from her soul? Does she really not believe good people can do anything if they set their minds to it? Why does he oppose caring for your aging parents? We definitely can't trust him with high political office.

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Replaying History

6 gworley 08 May 2009 05:35AM

One of my favorite fiction genres is alternative history.  The basic idea of alternative history is to write a story set in an alternate universe where history played out differently.  Popular alternate histories include those where the Nazis win World War II, the USSR wins the Cold War, and the Confederate States of America win the American Civil War.  But most of the writing in this genre has a serious flaw:  the author starts out by saying "wouldn't it be cool to write a story where X had happened instead of Y" and then works backwards to concoct historical events that will lead to the desired outcome.  No matter how good the story is, the history is often bad because at every stage the author went looking for a reason for things to go his way.

Being unsatisfied with most alternate histories, I like to play a historical "what if" game.  Rather than asking the question at the conclusion, though (like "what if the Nazis had won the war"), I ask it at an earlier moment, ideally one where chance played an important role.  What if Napoleon had been convinced not to invade Russia?  What if the Continental Army had not successfully retreated from New York?  What if Viking settlements in Newfoundland had not collapsed?  These are as opposed to "What if Napoleon had never been defeated?", "What if the Colonies had lost the American Revolutionary War?", and "What if Vikings had developed a thriving civilization in the Americas?".  I find that replaying history in this way a fun use of my analytical skills, but more importantly a good test of my rationality.

One of the most difficult things in thinking of an alternative history is to stay focused on the facts and likely outcomes.  It's easy to say "I'd really like to see a world where X happened" and then silently or overtly bias your thinking until you find a way to achieve the desired outcome.  Learning to avoid this takes discipline, especially in a domain like alternate history where there's no way to check if your reasoning turned out to be correct.  But unlike imagining the future, making an alternate history does have the real history to measure up against, so it provides a good training ground for futurist who don't want to wait 20 or 30 years to get feedback on their thinking.

Given all this, I have two suggestions.  One, this indicates that a good way to teach history and rational thinking at the same time would be to present historical data up to a set point, ask students to reason out what they think will happen next in history, and then reveal what actually happened and use the feedback to calibrate and improve our historical reasoning (which will hopefully provide some benefit in other domains).  Second, a good way to build experience applying the skills of rationality is publicly present and critique alternate histories.

In that vein, if there appears to be sufficient interest, I'll start doing a periodic article here dedicated to the discussion of some particular alternative history.  The discussion will be in the comments:  people can propose outcomes, then others can revise and critique and propose other outcomes, continuing the cycle until we hit a brick wall (not enough information, question asks something that would not have changed history, etc.) or come to a consensus.

What do you all think of this idea?

Great Books of Failure

26 Eliezer_Yudkowsky 19 April 2009 12:59AM

Followup toUnteachable Excellence

As previously observed, extraordinary successes tend to be considered extraordinary precisely because it is hard to teach (relative to the then-current level of understanding and systematization).  On the other hand, famous failures are much more likely to contain lessons on what to avoid next time.

Books about epic screwups have constituted some of my more enlightening reading.  Do you have any such books to recommend?

Please break up multiple recommendations into multiple comments, one book per comment, so they can be voted on and discussed separately.  And please say at least a little about the book's subject and what sort of lesson you learned from it.