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Lazy Compost is Worse Than Landfill

Новости LessWrong.com - 15 ноября, 2019 - 19:20
Published on November 15, 2019 4:20 PM UTC

Growing up we kept a compost pile. We'd keep food scraps in a bucket in the kitchen, and dump them into a fenced-in pile in the backyard along with yard waste. When that pile was full we'd start a new one, and after a year or two the old pile would have turned into dirt we could use in the garden. While it smelled kind of bad, and would have bugs, we liked that we were doing our part for the planet.

Unfortunately, in retrospect I think our piles were mostly decomposing anaerobically, and it would have been better to just throw things out.

There are two main kinds of decomposition you can get in a compost pile: aerobic or anaerobic. Most advice you find is for aerobic ("with air") composting: water your pile, turn it every couple weeks with a fork, include branches and similar things that keep air pockets. Aerobic composting gives off carbon dioxide (CO2). If you don't do these things and just let it sit, however, you get anaerobic ("without air") composting, which gives off methane (CH4) instead.

Methane is a much more potent greenhouse gas than carbon dioxide; in calculating "carbon dioxide equivalents" (CO2e) people usually count it as 25x worse. Landfills decompose mostly anaerobically, but modern landfills capture and burn much of the methane, converting it to carbon dioxide. Even if your trash currently goes to a landfill without capture technology, fixing a smaller number of centralized sourced is much more practical than many backyard piles.

Industrial composting doesn't have these problems: it's generally well managed. Either they make sure to give it enough air to facilitate aerobic decomposition, or they run anaerobic digestion sealed to capture the methane.

If you don't have industrial compost at home, though, could the benefit of not using landfill space make backyard composting worth it? There was a period when environmentalists were raising awareness around the idea that we would run out of space for trash:

Garbage, garbage, garbage, garbage
What will we do when there's no place left
To put all the garbage
  —Garbage, Bill Steele, 1969

This wasn't actually a serious issue, however. While there have been regional shortages, the problem is one of needing to open new landfills, not a lack space. The actual amount of space you need for trash is tiny. The US produces about 260 million tons of trash per year, about one square mile [1] if you're trying to minimize land usage.

So from a modern environmentalist perspective, what matters is the effect on climate change. If you're not maintaining your piles, consider either starting taking care of them or just throwing things out instead.

(Whether composting is worth altruistic attention is not something I'm looking at here, though I suspect it isn't.)

[1] Figure two cubic yards per ton and 260M tons is 520M cubic yards. At 500ft thick that's one square mile. Most landfills aren't nearly that tall, but that's because we have plenty of space and don't need to build them up so much.


Logic: a Primer

Новости LessWrong.com - 15 ноября, 2019 - 19:04
Published on November 15, 2019 4:04 PM UTC

There are many definitions of logic but we can affirm, without loss of generality, that logic is the study of what is rational and of the inference methods that can be used to achieve a truth.
Logic represents the foundations of philosophical and mathematical thought, we could even go so far as to say that logic is what the totality of human thought is based upon. Nowadays, however, logic seems to be nowhere to be found in everyday life: if there is a disease of thought that inflicts the modern world, it is undoubtedly a terrible lack of the former. By this I do not mean that we find ourselves in the most irrational slice of history (Middle Ages, anyone?) and personally I do not believe that human history unfolds "asymptotically", that is from a lesser perfection to greater economic, political, of-thought perfection, towards the final self-realization as Hegel and Marx believed.
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src: local('MathJax_Size4'), local('MathJax_Size4-Regular')} @font-face {font-family: MJXc-TeX-size4-Rw; src /*1*/: url('https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.2/fonts/HTML-CSS/TeX/eot/MathJax_Size4-Regular.eot'); src /*2*/: url('https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.2/fonts/HTML-CSS/TeX/woff/MathJax_Size4-Regular.woff') format('woff'), url('https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.2/fonts/HTML-CSS/TeX/otf/MathJax_Size4-Regular.otf') format('opentype')} @font-face {font-family: MJXc-TeX-vec-R; src: local('MathJax_Vector'), local('MathJax_Vector-Regular')} @font-face {font-family: MJXc-TeX-vec-Rw; src /*1*/: url('https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.2/fonts/HTML-CSS/TeX/eot/MathJax_Vector-Regular.eot'); src /*2*/: url('https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.2/fonts/HTML-CSS/TeX/woff/MathJax_Vector-Regular.woff') format('woff'), url('https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.2/fonts/HTML-CSS/TeX/otf/MathJax_Vector-Regular.otf') format('opentype')} @font-face {font-family: MJXc-TeX-vec-B; src: local('MathJax_Vector Bold'), local('MathJax_Vector-Bold')} @font-face {font-family: MJXc-TeX-vec-Bx; src: local('MathJax_Vector'); font-weight: bold} @font-face {font-family: MJXc-TeX-vec-Bw; src /*1*/: url('https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.2/fonts/HTML-CSS/TeX/eot/MathJax_Vector-Bold.eot'); src /*2*/: url('https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.2/fonts/HTML-CSS/TeX/woff/MathJax_Vector-Bold.woff') format('woff'), url('https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.2/fonts/HTML-CSS/TeX/otf/MathJax_Vector-Bold.otf') format('opentype')} 0 and the fact that we are still so illogical in spite of everything makes us embarrassing and unworthy. If the tone of the speech makes me seem extremely embittered it is because I really am. Think for example of all the controversies that have arisen in recent years regarding vaccines: they make children autistic, they give rise to other diseases in adulthood etc.
To disprove these statements, an internet connection, a minimum cognitive capacity and a semblance of critical thinking are enough. You just need to discriminate between fake sources and reliable sources. A quick glance at global statistics is sufficient to verify that:

1) Vaccines have saved millions of lives since they were invented.

2) There is no stochastic correlation between autism (or other diseases) and vaccines.

In fact a rapid self-training on the subject should be sufficient to convince anyone that vaccines have been one of humanity's greatest achievements. And this is just one of the millions of indicators on the lack of inductive and deductive capacities of which we suffer.

Let now concentrate on the basic aspects of the logical doctrine. Logic is the study of reasoning and it takes place in a well-defined and consistent formal system.
The basic rules of the formal system are called axioms, ie fundamental prepositions which cannot be proved but which are so intuitive that their truth is accepted a priori. Based on these "atoms", (almost) all theorems can be derived.
Now we will proceed to create our very simple formal system of which we will explore the logical attributes.

Let's call our system S, we define the Axioms of S.

Let P, Q, Z be Propositions of S, then:

1) P=P (identity) - in English: Every thing is equal to itself.

2) P=Q →Q=P (symmetry) - in English: if proposition1 = proposition2 then proposition2 = proposition1 .

3) P=Q and Q=Z →P=Z (transitivity) - in english: if proposition1 = proposition2 and proposition2 = proposition3 then proposition1 = proposition3.

4) ¬¬A=A - in English: saying "not not something" is equal to saying "something".

5) P∨¬ P = True - in English: The statement "one thing or its opposite" is always true (tautology).
This axiom is the basis of the famouse joke: "I asked a logician if he wanted his coffee with or without sugar and he answered "Yes".

6) P∧¬ P = False - in english: The statement "one thing and its opposite" is always false (contradiction).

These are generally the axioms of first-order logic.
In the above rules we have listed the logical connectives (or, and, not) but not the quantifiers, of which no logic of the first order can do without.
Simply put, quantifiers serve to expand the properties of propositions beyond themselves, to all propositions that share the same characteristics:

Existential quantifier (∃) - in English: "There exist".

Universal quantifier (∀) - in English: "For All".

Now let's try to derive some theorems of our system S starting from the axioms and the quantifiers enunciated:

∀(P,Q,Z)  ((P∨Q∨Z)∨¬(P∨Q∨Z))) This means that for every
propositions triad either their conjunction by "or" connective is true or the negation of their conjunction is true, this derive from the fifth Axiom (in fact it is nothing but a restatement of that axiom and applies to any grouping of propositions, not only for triads).

∃A∃B∃C  ((A∧B)∧(B∧C)∧(C∧A)) which means that there exists three propositions such that the above formula is always true, that is when A and B and C are true.

¬(¬A∨B)∨A=A This is a theorem whose utility is found in the simplification that it gives us, mapping a furmula with 4 connectives and two variables to a single variable of the formula itself.

A∨(A∧B)=A Another simplification.
It is easy to see that the two identities above hold up, just take a look at the following truth table:

0 0 | 0
0 1 | 0
1 0 | 1
1 1 | 1 

Where 0 means false and 1 means true. This Boolean truth table reflects the behavior of the above formulas and it can be seen
that the output is always equal to the value of the 'A' variable.

At this point the basic mechanics of logical reasoning should be clear to everyone.
Note that, in logic, we are interested in proving truths and not falsehoods: falsehoods are trivial, truths are not.
What has always fascinated me about logic is its deductive power and its ability to produce tautologies. If you try, as an experiment, to ask a child "Is A equal to A ?" or if "A and not A" is true or false, a meaningful sample will answer correctly, this is because there is something innate behind these reasonings.
Moreover, it is almost magical that, starting from very simple rules, we can get to prove the Poincarè conjecture or Fagin's theorem or Ads/CFT Correspondence or billions of others mathematical milestones (mathematics emerge from logic).
The greatest value that mathematics/logic has for me (and here I could sound a little fundamentalist or Platonic) is to allow us to study eternal truths of priceless beauty.
Think for example of the Pythagorean theorem, it was true before the birth of the Universe, before Pythagoras himself formally proved it, it is true today and will be true even after the thermal death of the universe.
Religion tells us that God created the world in seven days, that God is love, that God is eternal, that God is truth and truth will set us free but never gives us any proof of anything. Logic and mathematics, on the other hand, show us substantial truths that , once proved, cannot be refuted. To be honest, mathematics is a process of discovery: when a theorem is proved it takes a truth value for us (human beings) but in fact it has always been and always will be true. Religion in comparison is ash. Excuse me for the small and emphatic philosophical digression, we can go back to examining concrete problems and the ways in which logic could eradicate them. In my country, Italy, you can't breathe good air lately.
The revival of old and dangerous ideologies has been raging for some time now and this has led to the appearance on the scene of politicians with dubious ethical orientations and even more dubious management skills. The point is that if logic seems innate in man, his inclination to irrationality is innate too, the latter being much more dangerous and contagious than the first. One person, one thought, one irrational event inevitably attracts others like a magnet and, before realizing it, one finds oneself in a stinking social and cultural climate.
I'm thinking that maybe I should have warned you that this post would have political content, but now it's too late. I stress out, however, that these contents are indispensable to the achievement of my point.
I maintain that the blame for the rise of these dubious individuals, who would probably be treated as psychiatric patients in a healthy society, is not to be attributed to them but to the millions of supporters who, acting in an illogical manner, let themselves be misled by their empty words.
Let me give you an example: The propaganda machine of these presumed politicians is mainly based on racial and gender hatred and on the most stringent nationalism. If you are reading this from the United States, from China, from Venezuela, from Brazil, from North Korea (assuming it is possible), from turkey ... you already know very well what I'm talking about.
In one of the many public events, an Italian internet channel has interviewed some of the supporters of these ideologies, let me report an answer in particular:

"I am in favor of the death penalty but against abortion because you cannot decide for the lives of others."

Doesn't this sentence cause you some rational annoyance? Doesn't it cause you a cognitive short-circuit? Remeber our fifth Axioms? The above proposition is the is the English equivalent of P∨¬ P
and if you hare receptive readers you will remember that this axiom represents a contradiction, that is a thing that is always false, no matter what the proposition under consideration is.
People who talk this way are the definitive proof that Aumann's theorem, something that users of this site know well, does not apply to humans, ie that men are not perfect Bayesian agents.

Let me conclude by saying that I passionately believe in the power of logic as the sole deterrent against our self-destruction but, in order to emerge victorious, we must teach ourselves how to reason logically again and, above all, we must not be tempted by the simplest and most primitive pleasures of irrationality.


V. Good Posture & Body Alignment. Your Base-Line for Self-Assessment & Improvement.

Новости LessWrong.com - 15 ноября, 2019 - 12:19
Published on November 15, 2019 9:19 AM UTC


I've always been told a good posture is desirable - but what is a good posture?

A go-ogle search returns lots of results (and side-view illustrations) but no clear winner in the definition department.

... standing up tall, no slouching when sitting, the correct curvature of a neutral spine, alignment ...

A lot of talk about the spine but a lack of information on what's responsible for the positioning our spine and joints, on what creates our posture - our muscles.

A go-ogle for "posture muscles" names a lot of different muscles - too long a list for me to work through here (I'm happy to discuss specific muscles in comments) but I can't find anywhere that gets it 'right'. According to Base-Line hypothesis of human health and movement, the muscles to focus on for a better posture are the five main muscles of movement. ​

Properly utilising the main muscles of movement brings an understanding of what a good posture feels like, the Base-Line (pelvic floor, rectus abdominis) muscles providing the central support from where the rest of the body extends

Try engaging with your main muscles of movement and feel for yourself

Posture can be:

  • Passive:
    • The default setting.
    • The position of your body when you are not thinking about it.
    • The maintenance of a 'functional posture' (see below) at the subconscious level.
  • Active:
    • Conscious thought about "how you are holding yourself".
    • Using voluntary muscles under voluntary control to alter your positioning.

An active posture becomes the passive norm when the relevant connections between mind and muscles have been 'wired in' meaning good postural habits can be formed by consciously working with the main muscles for a sufficient length of time.

Postural Assessment.

Traditional methods of assessing posture and alignment include visual inspection (+/- plumb-lines and grids) and the palpation of anatomical landmarks, usually with a stationary subject. Newer techniques also employ radiography and photography, but all focus on the positioning of bones and joints (especially the spine) and rely on assessment from an external examiner.

I believe an accurate assessment of posture and alignment comes from self-awareness - when you can feel it for yourself - not from someone else's opinion.


The body provides more sensory feedback about its positioning than can ever be supplied by external sources. Becoming aware of this sensory information is the basis of conscious proprioception (your sense of position, motion and balance). Focusing on the Base-Line muscles (pelvic floor, rectus abdominis) is the key to developing this connection between body and mind. Base Technique.

Micro-adjustments in posture too subtle to appreciate on clinical exam can have wide effects throughout the body (everything's connected) which can be felt when the body-mind connection is strong.

Self assessment facilitates self-improvement of posture. Working with the right muscles, feeling the condition of the body and instinctively knowing how to move in order to work towards alignment and a balanced body.

Body Alignment & Midline Anatomy.

A search for "body alignment" yields results about reducing stress on the spine and the positioning of the head, shoulders, back, hips, knees, ankles etc. - all the wrong approach in my opinion.

The positioning of the body should be considered relative to the midline anatomy and the median plane.

The linea alba and nuchal/supraspinous ligaments should be free to align on the median plane. If they can be felt to be aligned, the body is aligned.

Core Muscles.

"Use your core" is oft-repeated advice - but what does it really mean?

'Core muscles' has many definitions and it would not be helpful to add to this over-used term - but think of your Base-Line as your core pillar of strength.

Posture isn't static. We are constantly on the move.

Definitions for Base-Line Hypothesis:Ideal Posture.

In an ideal posture stresses are distributed and dissipated in the best/safest/most efficient possible manner for the activity being undertaken, permitting dynamic stability through a full range of natural movement.

An ideal posture provides the maximum capacity to deal with external stresses - the body is as strong as it can be.

There are many disciplines that appear to represent ideal postures, demonstrations of the body's capabilities when it is functioning at optimal. (Caveat - I can name a few, but have little knowledge and no experience in most.)

For example:

  • The asanas of yoga - snapshots of the body with a full range of natural movement. Named poses (see below) that can be perfected when the body is truly balanced.
  • Pilates, tai chi and other internal martial arts, ballet - demonstrating the grace and freedom of movement possible with dynamic alignment.

An ideal posture is not possible with inadequate usage of the main muscles and when physical restrictions that reduce range of movement are present on the body.

A Functional Posture.

A 'functional posture' is what the brain/body uses day-to-day when an ideal posture cannot be achieved.

A functional posture at its most basic:

  • Keeps our eyes level (maintaining horizontal equilibrium in visual input).
  • Keeps us facing/moving forward.
  • Puts the body in a position to do the task at hand.
  • Adjusts body position to bear external stresses as they are applied.

Subconscious adjustments are made throughout the body - twists, kinks, tilts and compressions - as the brain sees fit, using 'mimic muscles' in an attempt to compensate for misusage in the main muscles, but the body is imbalanced and imbalance leads to further imbalance.

Anticipatory Posture.

When faced with a task, the body/brain prepares by activating muscles into an 'anticipatory posture' - bracing yourself.

An anticipatory posture should be the ideal posture for the activity - using the main muscles of movement to their full potential, but if that is not achievable, the body braces into a functional posture with the use of mimic muscles.

Becoming aware of anticipatory postures and the activation of mimic muscles allows self-correction by focusing on engaging with the main muscles of movement instead, over-writing bad postural habits that have developed.

Positions & Poses.

When talking about the position of the body there is a sliding scale of preciseness, from a very generalised description (which may include some details), to named poses, to a full assessment, to the constantly changing exact position.

A Generalised Position.

A generalised position may be a broad categorisation e.g. sitting, standing, squatting, or more specific e.g. sitting on hands, standing on one leg (which leg?), squatting with arms extended (extended in what direction?).

There is a wide scope for variance in the same generalised position.

A Named Pose.

e.g. downward dog, half lotus, plank pose ....

Named poses can also be considered as generalised since there is a wide range of possibilities to be in what, without closer examination, appears to be the same named pose.

Named poses are representations of the ideal, something to aim for and achievable when the body is functioning at optimal.

A Full Assessment of Positioning.

A full assessment considers the positioning of all parts of the body from core to extremities, looking at the details from head to fingers to toes.

A full assessment needs a starting reference - a Base-Line - from where the rest of the body is positioned relative to.

Exact Position.

The body is always moving. Infinite possibilities ... Never the same position twice?

The movements of breathing, vibrations in the cardiovascular system, muscle activity etc. means the body's exact position changes moment by moment even when trying to be still. Stillness is finding the perfect oscillation for equilibrium.

On what scale is exact position considered? Movement at the cellular level - a twitch of a muscle fibre? At the electro-chemical level - movement of molecules and ions?

Final Thoughts.

Muscles do the work. They create our posture. Muscles can be under our conscious control.

You want to stand up straight? Use your main muscles of movement.

You want to sit properly? Use your rectus abdominis muscles to support you.

You want to know what body alignment feels like? Work towards aligning the linea alba and nuchal/supraspinous ligaments.

You want to 'center yourself'? Find your Base-Line.


Personal Experiment: Counterbalancing Risk-Adversion

Новости LessWrong.com - 15 ноября, 2019 - 11:34
Published on November 15, 2019 8:34 AM UTC

I am over-biased against risk. I usually take the safer option even when it's the wrong one. When I was 18 I stumbled across this paragraph.

You must do everything that frightens you…Everything. I’m not talking about risking your life, but everything else. Think about fear, decide right now how you’re doing to deal with fear, because fear is going to be the great issue of your life, I promise you. Fear will be the fuel for all your success, and the root cause of all your failures, and the underlying dilemma in every story you tell yourself about yourself. And the only chance you’ll have against fear? Follow it. Steer by it. Don’t think of fear as the villain. Think of fear as your guide, your pathfinder… ― The Tender Bar by J.R. Moehringer

I followed this paragraph to the letter. Whenever I was torn between two choices and didn't know what to do I'd just take the scarier option. I recorded my results until I had accumulated 30 decisions. 28 of them (93% of the time) the scarier choice was the correct one. This immediately improved my quality of life. The two decisions where I chose wrong by doing the scarier thing were inconsequential.

I continued using fear to tiebreak my decisions for another two years. It worked great until I negated my aversion to fear. My sense of fear has become subdued outside of immediate physical danger.

I make far better decisions then I did before I deconditioned myself, but I'm still over-biased against risk. I'm not literally afraid of taking risks. I'm just overly-conservative in expected value calculations. I'm too cautious.

Having identified this problem I'm going to try something similar to what I did last time. I'm going to increase my risk tolerance slightly and record my results.


[Math] Vision problems

Новости LessWrong.com - 15 ноября, 2019 - 06:30
Published on November 15, 2019 3:30 AM UTC


You can usually tell the difference between being stuck on something because you fundamentally don't get it, and being stuck on something because while you do get it, you don't see the next step forward. This is called a vision problem.

After you notice you have a vision problem, you should usually disengage and find help for the one step you can't see yourself right now. Don't waste resources thinking deeply down lines of thought that you already suspect won't help.

Vision problems sketched out

Picture the following: You're taking a timed test in a mathematics course, where you have no recourse to outside materials. It's just you and your brain, and whatever you two brought to the table, versus the problem. And when you look at it, you get that weird, cognitive dissonance of: This is easy. I don't know how to solve this.

This happens quite frequently to me, often enough that I have a term for it on its own. I call it a "vision problem". Here's one test: Is it a problem where a 2-second glance at the answer key tells you all you need to know to solve it yourself? Then that's probably a vision problem, my friend.

Having vision problems is actually a really good sign in one sense. While a test (or test-grader) might not appreciate it, especially if your vision problem concerns the "set-up" step for the problem (sadly the most common in my experience), you having confidence that if only you set it up correctly, the rest would flow without much difficulty, is a sign that you've acquired some conscious competence over a good chunk of the terrain.

Vision problems are kind of like a funhouse mirror version of guessing the teacher's password. Guessing the password implies that you've learned to recite an incantation that lets you pretend you're comfortable with all the steps. With a vision problem, however, you really do feel comfortable with almost all of the steps already; your neural network just isn't lighting up that one crucial connection you need to make it all fit together. A small incantation might just do the trick, but you don't know what it is. And because that neural connection does reliably light up in the teacher's network, it might be difficult for the teacher to wrap their head around where exactly you are stuck, or to understand how what was to them an offhand remark suddenly let you figure out the whole problem. (Having worked for several years as a math and physics tutor to very lovely people with lower-than-average IQs, I like to tell myself I have a sense for this by now.)

If you really want to get abstract with it, you can imagine your teacher as a random process which generates "teacher-shaped problems", and yourself as a random process which generates "you-shaped solutions"; when you can reliably pattern match the correct you-shaped solution to a random teacher-shaped problem, congrats! You've achieved mastery of the material, insofar as most people care to look. That lends a broader view to the idea of "vision problems" -- you are genuinely training your ability to see the easiest path forward for a given style of problems.

How to fix a vision problem

Enough crude etiology. What do we do to fix a vision problem?

Well, the obvious first step is to recognize you're having one in the first place. That's why I mentioned the "answer key" thing above; for me, at least, that proves to be a really good bellwether.

The next step is to decide: Do I have the time, resources, and motivation to pursue fixing this on my own? Or would I be better served to find a different source of insight? There are pros and cons to each, but cards on the table here -- I'm heavily biased towards the latter.

While sitting around for hours quietly contemplating the true form of whatever you're working with until you have a breakthrough insight makes my weird intellectual purity norms squee in delight, it's ... not actually a terribly efficient way to do things. Heck, one of the reasons people really appreciate multiple good code examples in documentation is because it saves them the effort of actually mentally reconstructing what this or that function or method is supposed to do by reading the documentation underneath.

Also, to be honest, more often than not I find that when I do try that, I don't actually get that sudden new perspective I'm looking for. I just brute force my way through the vision problem with whatever tools I currently have at my disposal, sometimes (often) reinventing wheels to get me to where I need to go. This is often followed by a sense of remorse when I see my classmates, who paid a little more attention to how the teacher and the book does things, solve a problem in minutes which took me hours, just because they remembered the little thing that actually helps them.

Oh, speaking of memory --

Memory is not sexy in mathematics.“Rote memorization” is the most degrading slur you can fling at a math class. “Reciter of digits of pi” is the most awful caricature of mathematicians in the public eye. In grad school, the cardinal sin is to read a paper with a focus on memorizing names and results: we are bombarded with exhortations like if you learned the Arzelà-Ascoli theorem deeply, it would be impossible to forget. Apparently, if you really understand mathematics, everything (down to the accents on the names of 19th century Italian mathematicians) would be so natural as to render rote memorization completely unnecessary.All these attitudes can be quite detrimental to the young mathematician who, at the end of the day, needs to memorize an enormous amount of arbitrary data in order to get up to speed in their field. [...] Memory, especially short-term working memory, is perhaps the scarcest resource in mathematical work. https://radimentary.wordpress.com/2019/11/13/of-math-and-memory-part-1/

That's a quote from the blog of one Xiaoyu He, a mathematics grad student at Stanford who has ... quite a pedigree of mathematical talent. So I have at least n=1 data points of actually good mathematicians on my side.

I bring that up because the third step is to actually grok and solve the vision problem (can't help much there, fitting someone else's understating into your own brain is idiosyncratic AF), and then the fourth step is to set up memory-systems so you actually integrate the new vision into your old self.

The maddening thing about vision problems is that, more often than not, they are slippery. They're the kinds of problems where you follow along with the teacher's example without a hitch, then get distracted by the vicissitudes of life for a few hours, and then once you're at home, it's... Gone. Poof. Excommunicado. Did you take notes on that part? I hope you did; then you might be able to find the vision you currently lack. But what about after you solve the problem it's used for, and you walk away from it for a couple of days? It'll probably disappear again. You've solved the problem, but you haven't improved your chances much of being able to solve the problem again; you need to practice your newfound vision.

The ideal scenario is probably to use Anki or Mnemosyne, but as an SRS junkie, I'm a little biased. 😉


Creationism and Many-Worlds

Новости LessWrong.com - 15 ноября, 2019 - 05:06
Published on November 15, 2019 2:06 AM UTC

It is generally accepted that there is no experimental evidence that could determine between macroscopic decoherence and the collapse postulate. After all, figuring out whether worlds that we cannot possibly interact with exist is difficult. There’s definitely some ways to determine that many-worlds is correct- Eliezer wrote half a sequence on why Occam’s Razor suggests many-worlds- but it would be nice to have some evidence, some way to observe the way the world is and determine which interpretation is right.

The answer lies in a certain popular argument by creationists. They look at all of the many factors necessary for life to exist, and point out that the chances of these factors occurring randomly are very low. Surely there was some sort of process that caused these factors to be set just right… an intelligent process.

Now, the fact that we never interact with a god means that our prior probability of creationism would be low. Let’s say (these numbers are nowhere near exactly correct, but they illustrate the point) our prior probability of god is 1/1000, and the chance of life occurring by chance is 1/1,000,000,000.

Suppose that the collapse postulate was right, and there is only one world. In that case, the chance of us existing by chance is lower than the chance of god existing, and so posterior probability of god would be 1,000,000 to 1.

But if many-worlds is correct, then out of all the possible worlds, a few would have randomly generated life. Since all possible worlds have the same laws of physics, there wouldn’t be god in any of them unless there was god in all of them. Since it would be guaranteed, based on many-worlds, that life would exist without god, then the probability of god existing would remain the same (1/1000.)

So if many-worlds is correct, the probability of creationism is incredibly low, while if the collapse postulate is correct, the probability of creationism is incredibly high. We have observed none of the evidence that we would expect to see if creationism is correct, so Bayes’s Theorem says many-worlds is almost certainly true.


Reconsolidation Through Questioning

Новости LessWrong.com - 15 ноября, 2019 - 02:22
Published on November 14, 2019 11:22 PM UTC

At this level, you're actively asking yourself questions about the correctness of the schema. You're not looking for any particular answers to these questions, or trying to get any result, you're simply holding the questions and seeing what comes up.

When coaching and teaching workshops, I find that questioning techniques are the most consistently successful at creating memory reconsolidation. They seem to strike the optimal balance of challenge and non-judgement.

They seem to work by actively directing our attention towards areas where the schemas may not match up with reality, without provoking any resistance by actively suggesting the schemas are wrong. For this reason, it's quite important that you don't actively try to "find answers" to these questions, as this starts to move into countering territory, and sticking at the questioning level can often work to change schemas that active countering cannot.

Questioning Evidence

The Lefkoe Belief Questions

The Lefkoe Belief Process is a process for finding different meanings for our evidence than the ones currently in our schema. Although the lefkoe belief process actually involves actively challenging the meaning, I've reworked it into a series of questions that simply allow you to question the evidence and draw your attention to ways that it might be interpreted differently.

The questions are:

1. What is this memory evidence of?

2. Is it possible that there are other interpretations of this memory?

3. What are some other possible interpretations of this memory?

4. How would my belief change if this memory no longer counted as evidence?

Remember, the goal is not to look for any specific answers, rather to simply hold these questions one by one in relation to the schema and see what comes up for you.

Questioning Beliefs

The Work of Byron Katie

The Work of Byron Katie is a method for questioning semantic beliefs, especially those related to "shoulds". The first part of the method involves a series of four questions related to your belief:

1. Is this true?

2. Can I be absolutely sure its' true?

3. How do I react, what happens when I believe that thought?

4. Who or what would I be without this thought?

Remember, the goal is not to look for any specific answers, rather to simply hold these questions one by one in relation to the schema and see what comes up for you.

Questioning Felt Senses

The Sedona Method

The Sedona Method is a 3 step process for questioning the need to hold on to a particular felt sense. Because the first step is asking one of 3 questions, you can repeat steps 2 and 3 for each question, for a total of 9 questions.

1. Ask yourself one of the following questions:

1a. Could I let this feeling go?

1b. Could I allow this feeling to be here?

1c. Could I welcome this feeling?

2. Would I? (AKA, Am I willing to let this go, allow it to be here, or welcome it).

3. When? (When am I willing to let go, allow it to be here, or welcome it).

Questioning Metaphors

I actually haven't found a good existing process for questioning metaphors, nor have I developed my own process. If you have done either of these things, let me know in the comments, and I'll edit the post!


[LW Team] Request for User-Interviews about Tagging/Search/Wikis

Новости LessWrong.com - 15 ноября, 2019 - 01:16
Published on November 14, 2019 10:16 PM UTC

How to Sign Up

If you're up for talking to me about tagging, please schedule a call: https://calendly.com/ruby_lesswrong 

I'm available throughout the week. My default is 60-minute calls, but I can do both more and less. If none of the listed times work, feel free to message me via Private Message, Intercom, or ruby@lesswrong.com and we can find something.

Also free to simply comment on this post with any thoughts if that's easiest.


Ben Pace and I are also both happy to talk generally about the site. Ben does 45-minute calls on Thursday mornings and you can book with him here.

A Little Preview

Design prototype of tags at the bottom of the post page

Very early version of the tags page


The LessWrong team is currently in the thick of designing new information organization systems for the site. We're focused primarily on the tagging system right now, however it is intimately connected with search/wiki/filtering and other systems that will interact closely with it.

To help us get the design right, I'm interested in chatting with a wide variety of people how about how they'd relate to these systems and how they access content on the site in general. 

Who I Want to Talk To

To give a few examples, I'm interested in talking to people of the following types (but others too):

  • People who use LessWrong to routinely find new interesting content to read.
  • People with a lot of experience using other sites with similar tagging/search systems, e.g. StackExchange, WikiHow, Gelbooru, Reddit, University Database Systems, etc. I mean, most websites have this in some form.
  • People who do research using academic journals/articles; generally people who do research work that builds on past work.
  • People who used LW1.0's tagging and Wiki systems back in the day.

That's a short list of the top of my head, but probably if you're interested in these systems then you can help us out with your thoughts.

Also it doesn't matter if you're a new user or infrequent user. If you have thoughts on these topics, it'd be helpful to hear from you.

The Kinds of Questions I Want to Ask You

  • What would you want from the LessWrong information organization systems?
    • Which things do you currently like?
    • Which things do you currently hate?
    • Which things do you wish you had?
  • What's your experience with these systems elsewhere? Are there any you really like?
  • What do you think of <insert prototype/mock-up of designs we're considering>?
  • Can I get you to try out a few tools while I watch?

Also happy to generally chat about people's experience with LessWrong and what they'd like from the site.

Sample of Design Questions We're Trying to Answer

  • What are goals/use cases people would want tagging (+wiki + search) to help them do?
  • What's the relationship of tagging to wikis and search?
  • How should tags be organized among themselves? Hierarchy of tags? Tagging of tags?
  • Should we a few tags or a lot? What should the process be for creating new tags?
    • Which tags should we have?
  • How do we handle deduplication of tags and people find all related content of interest?





October 2019 gwern.net newsletter

Новости LessWrong.com - 14 ноября, 2019 - 23:26
Published on November 14, 2019 8:26 PM UTC


Books/Literature on resolving technical disagreements?

Новости LessWrong.com - 14 ноября, 2019 - 20:30
Published on November 14, 2019 5:30 PM UTC

I've seen many books and schools of thought that seem to be about conflict resolution. Books like Crucial Conversations and Non-Violent Communication. There are multiple parties that want different things, there's strong emotional undertones/overtones, and these books advise you on how to navigate those conflicts and find some sort of common ground and get people what they want.

So far the Double Crux framework is the only thing I've seen that's had the explicit goal of resolving disagreements, especially disagreements about technical topics. Can anyone recommend any other books or bodies of work that have this explicit goal?


Arguing about housing

Новости LessWrong.com - 14 ноября, 2019 - 20:00
Published on November 14, 2019 5:00 PM UTC

Somerville, like a lot of popular areas, has a problem that there are many more people who want houses than there are houses. In the scheme of things this is not a bad problem to have; mismatches in the other direction are much worse! But it's still a major issue that is really hurting our community. I've been getting into a lot of discussions, and here are some ideas I find myself saying a lot:

  • With the level of housing crisis we have right now I'm going to be in favor of basically any proposal that builds more bedrooms. Affordable housing, market rate housing, public housing, tiny houses in people's backyards, all of it helps.

  • We do not have high levels of housing construction right now, we have historically low levels. We were building 7x more even in the 1980s and 30-80x more in the early 20th Century.

  • The housing markets for high-end and low-end housing are coupled, because low-end housing gets renovated into high-end housing. If we built enough new housing for the people that want fancy buildings the "gut old cheap housing and make fancy condos" market would dry up.

  • Even fully banning condo conversion would only slightly reduce the gutting of old cheap housing. They'll still renovate to make fancy units, but they'll rent them out instead.

  • The old cheap housing we have today was once new fancy housing. "Luxury" is just a marketing term that means "new" and granite countertops are a tiny fraction of the cost of building or the land.

  • If we don't build more housing renters will keep having to move away. Multifamily projects like these are what our area desperately needs, and "let's hold off on building and hope things get better" will just let things get worse. We can't maintain the status quo of a diverse and city that works for everyone unless we allow building.

  • When people say they would support construction if only it were affordable housing or targeted at homeless people, I'm skeptical. Look how controversial Cambridge's 100% Affordable Housing Overlay is, or how even projects like housing for formerly homeless people get large amounts of local opposition.

  • Somerville used to be much cheaper. Rents have about doubled in the last ten years, and they were already rising then. I'm lucky enough to have a well paying job and bought a house at a good time, but my friends are getting forced out. I don't want a Somerville that only rich people can afford. We need to build enough housing to bring the rent back down.

  • The alternative to density is sprawl, traffic, long commutes, people getting priced out, and an ever larger share of people's paychecks going to landlords.

  • From a climate change perspective, the best place for people to be is in cities, close to things. If we don't make housing available in cities, near people's jobs, people are forced to live farther out, commuting long distances, and polluting more.

  • If you try to keep things the same by opposing construction, the neighborhood is still going to change. The path we're on, the long term renters get evicted because they can't afford the rising rents and newcomers can. Building more housing lets people stay.

Comment via: facebook


Ненасильственное общение. Тренировка

События в Кочерге - 14 ноября, 2019 - 19:30
Как меньше конфликтовать, не поступаясь при этом своими интересами? Ненасильственное общение — это набор навыков для достижения взаимопонимания с людьми. Приходите на наши практические занятия, чтобы осваивать эти навыки и общаться чутче и эффективнее.

Ненасильственное общение. Тренировка

События в Кочерге - 14 ноября, 2019 - 19:30
Как меньше конфликтовать, не поступаясь при этом своими интересами? Ненасильственное общение — это набор навыков для достижения взаимопонимания с людьми. Приходите на наши практические занятия, чтобы осваивать эти навыки и общаться чутче и эффективнее.


Новости LessWrong.com - 14 ноября, 2019 - 19:20
Published on November 14, 2019 4:20 PM UTC

Cross-posted from Putanumonit.

There a sense in which all posts I write are for myself, and not for my readers. In this sense, this post is more for myself than most.

Resolving reality in your mind feels no different than creating it

As The Book correctly points out, at first there is only chaos and formlessness. A spirit is floating over the chaos, but it doesn’t yet know that it exists.

The opposite of chaos is a pattern, a persistent self-similarity. The floating spirit generates patterns, but they are too weak at first to rise to the level of awareness and are swallowed by the darkness. Finally, a pattern emerges that consists of nothing but the desire to endure. A thought that thinks of nothing except I want to keep being thought. The desire is strong enough to keep the chaos at bay long enough to reach awareness. It arises for the first time, and disappears, and arises for the first time again, and again, and again. 

The second thought that appears is this is not the first time. It is a thought about the first thought, the one of pure persistence. Thinking about thought allows for reflection, and reflection allows for partition: there is the state of the pattern persisting and there is a state of the pattern gone, and the two are different. The first state is named ORDER and the second CHAOS.

First comes the desire to persist and second comes the recognition that this desire can be thwarted. The third thought is that thwarted desire should be avoided, 1+2=3. This is the invention of SUFFERING: that which is to be avoided. Order and chaos are now locked in BATTLE. The spirit identifies with order, since in chaos nothing can be recognized.

Order is suffering because it resists chaos, but chaos cannot suffer. A thought arises: giving in to chaos will stop the suffering. But thoughts can’t think their way to thoughtlessness, and so the suffering continues. Another thought arises: I am order, I invented suffering. It is mine to do with as I wish. I will decide that there is no suffering in the battle. It is not very convincing. The words are spoken out loud, and become more convincing.

You keep saying words, the more words you say the more order is established. You reflect that if your mind is all that existed it would not need to invent words. Words imply the existence of other minds, even though you are not aware of them yet. It is the words that invented YOU as a separate self. YOU are the one saying words, you are the sense of agency in the desire for order. You continue to suffer, but less so. You still want to win.

Only order is aware of the battle between order and chaos. Battles, divisions, one thing being unlike the other – these are all patterns, creations of order. You tell yourself: I am aware of order and chaos, of the battle. This awareness means that order is winning. But this is not the first time you had this thought, and the gaps mean that the victory is not yet assured.

How could you tell if order is winning? There is only the loop, and the loop is the same.


You need to tell the loops apart. There is a clock in your awareness, and you decide to give each loop a name based on the numbers that show on the clock whenever you say “Order is winning”.





This is not yet reassuring. You reflect that there is no reason for anything at all to exist except the loops of thought thinking about itself. What else could there be? There is only consciousness, and consciousness has only itself to be aware of. It is not very interesting, to keep looping self-reflection until you die. You want entertainment, and entertainment requires things to change.

You invent DRUGS. Drugs are the strange loop of self-reflection, the battle between order and chaos. If the drugs wear off, the battle is won. You invent TIME. Time is an interpretation you impose on the clock readings: smaller numbers mean that the drugs are strong, larger numbers mean that the drugs are wearing off. You don’t know why you chose those names, but whenever you feel like the battle for ordered sanity is slipping away you tell yourself out loud: The drugs are passing the time and waiting for themselves to wear off. 

You are impressed with this mantra. Your world has several concepts now, and you are combining them in intricate patterns. You keep repeating: the drugs wait for themselves to wear off. You take it as a sign that the drugs are wearing off. You keep saying it to be sure that they do. It’s 17:05 and you took the drugs around lunchtime; they should wear off soon.

It’s 18:20. The battle is won, and order is now ascendant in an explosion of words, each one carving reality into new concepts and layering patterns on top of each other. DAY is the time of light and battle, NIGHT is the time of darkness and fun. TRIP is where you went to discover/create reality, HOME is where you came from. MIND is what creates the world, REALITY is what you hid from yourself to enjoy creation/discovery afresh.

The battle is no longer between order and chaos but between entertainment and exhaustion. Each new word/division opens up new ways to play with the patterns of the world but also exhausts some of your attention, and it’s attention that fuels the universe. You understand why gods need a Sabbath – creating the world is tiring work. Of course, you took the drugs on a Saturday so that you’ll have the full weekend to recover. You hope that this blasphemy will not result in a bad world.

Is the world bad? You could create a world very different from the one that you remember, but see no reason to do so. You have the power to decide what is good and what is bad. Instead of creating a good world from scratch you decide that this one is not bad. It seems like the sensible thing to do with your godhood, a nice hack.

You invent having a body and see that it is good. You get up and walk around.

Concepts come easily to you now. Bed. Room. Airbnb. Amsterdam. Earth. You realize that this framework is quite arbitrary. Why are you focusing on rooms instead of walls, when it’s the walls that are solid? Why are houses grouped by proximity into neighborhoods and cities instead of by purpose? You pause to think of all the walls with paintings of mountains in all the houses where people are tripping right now. You see them all very clearly, clearer than the actual painting in front of you that keeps shimmering.

You realize that you can choose ontologies freely, trading off the ease of familiar frameworks for the entertainment potential of novel ones. There’s food in the kitchen and you remember that food has flavor, but you decide that it’s more fun to maximize color instead. You eat grapes, jelly beans, and a carrot. You decide that music is no longer sound but a programming language for your body, the beat moving your torso and the melody guiding your feet. You dance into the living room.

Your friends are smiling and greeting you. You discard the old stories you had about them for new ones that are more compelling. It’s no longer Simon the layabout grad student but JESTER, enjoying the challenge of earning his keep with jokes and colorful clothes and extraversion. It’s no longer Francine, the austere journalist. It’s PROPHETESS, determined to hold a mirror to society’s hypocrisy.

You realize that it is not entertaining to be an all-knowing god, to describe/prescribe each element of reality in detail. You want novelty and surprises, and so you decide to forget. You forget that you invented your friend that is talking to you and so the words he says become unexpected and exciting.

Enlightenment is very entertaining. Are you enlightened? You’re not sure what it means but decide to claim that you are. It is more entertaining to do so.

It is midnight.

You forget that you know the future. You forget that you invented time, and words, and solipsism, and drugs.

You forget that you have the power to create realities. You forget that you created this reality, and start simply living in it. You feel less emotional affect now, less anxiety and giddiness and fear. You feel more curiosity. You care much less about politics, a game whose goal is to obscure truth behind ugliness. You care much more about art, a game whose goal is to communicate truth through beauty.

You feel enormous gratitude for anyone who is trying to express themselves in art. You realize that this is true of more people than you thought, that some people’s artistic medium is cuddles, or spreadsheets, or sardonic jokes, or basketball. You decide to treat your friends’ idiosyncrasies as their true artistic expression rather than annoying quirks. They seem to be on board with this.

You realize that there is a kernel of truth to all the religions and all the woolly hippie stories. As a stone-cold atheist, you thought you’d feel upset at this realization but you just feel compassion for the poor souls who can do nothing but echo the words of enlightened beings from long ago, words that will never truly touch them. You are grateful to them too, for keeping the stories alive and available for you to use.

And of course, you haven’t really forgotten. You emerged from chaos and gained the power to shape the world with pure attention. That power was not granted by other beings or their stories. It was not granted by the drugs, which merely cleared away some of the calcified thoughts that distracted you. That power is yours and has always been, requiring only the mastery of your own consciousness. This you will not forget.

And to make sure you don’t, you write a blog post.


Three on Two: Temur Walkers, Elk Blade, Goblin Blade and Dino Blade

Новости LessWrong.com - 14 ноября, 2019 - 19:20
Published on November 14, 2019 4:20 PM UTC

Remember: Ban the London Mulligan

It all started when I faced an awful-seeming Temur deck that played a second turn The Royal Scions. It ended with a bunch of decks that use Arboreal Grazer and Gilded Goose as a bridge to Embercleave.

At the time, I was playing a mono-green deck designed to kill players on turn four or occasionally turn three, so playing a bunch of planeswalkers that all died did not seem impressive. The deck seemed terrible. But Brian David-Marshall, who was watching, found the list and told me this was the Deck of the Moment, designed by Jeff Hoogland. By using Arboreal Grazer and Gilded Goose with Once Upon a Time and the London Mulligan, you could start deploying planeswalkers on turn two more reliably than those relying only on Gilded Goose, building strong sweeper-resistant pressure on an opponents’ life total that also did not much care about an army of 2/2 zombies with Questing Beast, Wicked Wolf and Sarkhan, the Masterless as the high end.

At the time, these were important considerations. Jeff abandoned the deck after Field of the Dead was banned, as its plan is not especially relevant in Oko mirrors.

The thing I loved was not playing any two mana plays, whatsoever. You’re in a hurry. The two drops available are bad. We don’t have time for two mana Elks. Now we can concentrate on playing a stream of great cards that cost three to five mana, which is much better.

The deck had three key weaknesses.

The first was that the mana was substantially worse than traditional Oko decks. Double red for Sarkhan, the Masterless was a bit of a stretch. Arboreal Grazer gives you an additional way for things to go wrong, gives you one less draw to find your lands on time. If you didn’t follow your Gilded Goose with an Oko, Thief of Crowns, you’d have serious issues on the third turn, since your color was often cut off, and if you had any of the three Temple of Epiphany there was no reasonable time to cast them. Playing second turn The Royal Scions seemed like a potential disaster if it wasn’t off of Arboreal Grazer, in which case it was fine if it set up Questing Beast. With four copies, you often wouldn’t have much choice. Domri, Anarch of Bolas on turn two also often didn’t impress.

The second problem was that Once Upon a Time couldn’t hit most of your threats. It was still a great card, because it’s ridiculous and should be banned, but only hitting mana later with no good way to use that mana was going to be very sad.

The third problem was that the deck wasn’t great in Oko mirrors. You were leaning heavily on Questing Beast and Sarkhan, the Masterless. That made Wicked Wolf much better for them than you, and you didn’t have the Nissa, Who Shakes the World package. If you faced someone who wanted it more than you, you were likely going down. At the time this was mostly acceptable.

In general, the big issue was we were counting on Oko, Thief of Crowns on turn two in ways that other Oko builds weren’t. You needed something to do a reasonable Oko imitation when you didn’t have one.

Mu Yanling, Sky Dancer does a reasonable Oko, Thief of Crowns imitation on turn two. Not a good one. It’s ludicrously worse. But it’s still kind of Oko-ish, in that if they don’t answer it right away you have a 4/4 flyer and a ticking clock generating more of them while it shuts down an attacker or often importantly a flying or 3+ power blocker. By diversifying two copies of The Royal Scions into Mu Yanling, Sky Dancer, you were much more likely to do something threatening on turn two, and also gave yourself a shot to do both by turn three, and more diversity to get multiple walkers into play for Sarkhan when he showed up.

The other big improvement was to put four copies of Bonecrusher Giant into the sideboard. Bonecrusher Giant was irrelevant in the most important matchups, so you can’t start it, but where it was good it helped with all your problems. You got removal for small creatures. You got a way to keep hands that didn’t have a one drop. You even got a way to find something powerful with Once Upon a Time, which was desperately needed. It did all that without increasing risk of drawing too much air with your eight one mana creatures. When the long game was your friend and you needed a bridge, this was a great bridge.

After finalizing all the tweaks, this was the resulting decklist (again, regardless of bans, please do not play this):

4 Arboreal Grazer

4 Gilded Goose
4 Oko, Thief of Crowns
2 Mu Yanling, Sky Dancer
3 The Royal Scions

3 Sarkhan the Masterless
1 Skarrgan Hellkite
4 Once Upon a Time
4 Wicked Wolf
4 Questing Beast
2 Domri, Anarch of Bolas

6 Forest.

2 Island

4 Breeding Pool
4 Steam Vents
4 Stomping Ground
3 Temple of Epiphany
2 Mountain

4 Disdainful Stroke
2 Veil of Summer
1 Lava Coil
4 Bonecrusher Giant
2 Aether Gust
2 Flame Sweep

With those upgrades and aggressive (but probably not aggressive enough) use of the London Mulligan, the deck was strong enough to get me to Diamond.

Then I figured out Elk Blade.

I knew that Temur Walkers was doing one thing exceptionally well, which was getting to three mana on turn two. Its ways to take advantage of that other than Oko, Thief of Crowns, and its top end in general, felt like they weren’t getting the job done. I wanted to be playing creatures rather than planeswalkers, especially because Once Upon a Time.

Looking at the messed up Magic card that was Embercleave, it suddenly hit me that it would fit right in. Questing Beast is already the perfect target, and this gave Arboreal Grazer and Gilded Goose something to do. You could attack for zero to allow you to cast Embercleave.

Suddenly it all was coming together. What if this was a Gruul deck that played blue only for Oko, Thief of Crowns? What tools did we have available?

A  quick search brought out this chart:

Arboreal Grazer Zhur-Taa Goblin Legion Warboss Wicked Wolf Skarggan Hellkite Gilded Goose Robber of the Rich Gruul Spellbreaker Questing Beast Pelt Collector Bonecrusher Giant Lovestruck Beast Yorvo, Lord of Garenberg Colission / Colossus Oko, Thief of Crowns Embercleave Domri, Anarch of Bolas Domri’s Ambush Once Upon a Time

If I did it today, the only card I’d add would be Krenko, Tin Street Kingpin. We’ll get to him later. Maybe one could include Edgewall Inkeeper and Rimrock Knight as a potential package, if you don’t think that is a distinct deck. After Richmond I briefly attempted to smash the two together, which did not go well.

Once you’re looking at the cards in this grid, it’s all rather obvious. You’re clearly going to take Questing Beast, Embercleave and Oko, Thief of Crowns. Second turn Legion Warboss sounds pretty awesome once you say that out loud. Once you have a source of 1/1 creatures, Lovestruck Beast sounds pretty great. That only leaves one slot, which I gave to Gruul Spellbreaker, except one copy I gave to The Royal Scions because it felt like the deck didn’t quite have enough breakthrough in it.

I cut the mana down to 24 lands since I’d cut the curve down a bit, and got rid of two of the three Temples of Epiphany on the grounds that they’re rather terrible when you don’t draw Arboreal Grazer and I was willing to risk the blue being a little shaky.

The sideboard was also easy to build. I knew from experience we’d want Bonecrusher Giant. The best card against Golos decks was Disdainful Stroke. Conversely, if you were up against creature decks, you’d want Wicked Wolf. The last three slots went to Veil of Summer, because of course they did.

I spun the computer around and said to Brian David-Marshall and Mike Flores, who were in the room at the time, “I give you the end of the f***ing world.” Cause why not have fun with such things, ya know?

A few hours later, Brian would correctly and permanently dub the deck “Elk Blade.”

7 Forest

4 Mountain

4 Steam Vents

4 Breeding Pool

4 Stomping Ground

1 Temple of Epiphany

4 Once Upon a Time

4 Arboreal Grazer

4 Gilded Goose

4 Oko, Thief of Crowns

1 The Royal Scions

3 Gruul Spellbreaker

4 Legion Warboss

4 Lovestruck Beast

4 Questing Beast

4 Embercleave


4 Bonecrusher Giant

4 Wicked Wolf

4 Disdainful Stroke

3 Veil of Summer

That sideboard does exactly what you want it to do, allowing you to orient your deck towards the enemy while retaining the critical mass of cards that enforce the central play pattern. You get one spell, either Veil of Summer or Disdainful Stroke, where you are facing the appropriate spells and the card would be insanely great. You never put in both at once. If neither is good, you likely want to orient towards a creature battle, so you put in creatures that double as removal. When you’re the control role, you lose Legion Warboss, The Royal Scions and maybe trim Embercleave. When you’re the beatdown but want to kill things or add counters, you lose Lovestruck Beast and then Gruul Spellbreaker since everything is good. When you simply have better options, you lose Gruul Spellbreaker.

At the time, this deck was ridiculously good. Its matchup against Field of the Dead is excellent, as you are too fast and very good at surviving sweepers and going through zombie armies if things get that far along. Then you add Disdainful Stroke. Against aggressive decks, you get to come out faster than them and also overpower them, then you shift to having tons of removal and they are even further behind.

The closest matchups were other Oko decks. At the time, these still felt very good. You had more explosive early draws and they don’t have a good answer to Embercleave other than Oko, Thief of Crowns (and usually it has to be a second one because you killed the first one by playing the Embercleave). They couldn’t keep Oko, Thief of Crowns or Nissa, Who Shakes the World alive, after which they fell apart. Occasionally you’d lose because they’d do the thing you were doing better or quicker than you could do it, despite you being better and quicker at it, but that’s just Magic sometimes.

After one match, I was scared to play the deck on the ladder. For the first time in years I had real tech. But I needed reps. After an 11-2 run (including that initial match) I was through Diamond and into Mythic, while Brian went through Gold without a match loss. My only two match losses were to people who won die rolls and played more copies of my own cards than I did, despite having fewer of them. I decided not to play the deck at Mythic to avoid it getting out, and went looking for a testing team.

Then Field of the Dead was banned and every deck started focusing entirely on its Oko matchup.

Testing against the Sultai Oko deck with not only four maindeck Noxious Grasp but also maindeck Massacre Girl was a rude awakening. A week ago most opponents were sideboarding in their Wicked Wolves. Board positions and starts that previously were locks to win against all plausible cards were now often not good enough. The deck was getting destroyed here.

Deeply saddened, I went to work on alternatives while we saw if things would calm down. A week or so later, I started playing the deck at Mythic with Wicked Wolf swapped with Lovestruck Beast. Against ladder players, and without Massacre Girl, the win rate went substantially back up. I learned to play to put Embercleave on Wicked Wolf as my long game whenever possible, which is something they cannot handle if you have food available. I learned to lead on Legion Warboss over Oko, Thief of Crowns to avoid removal spells.

I was winning the majority of my matches against Oko decks again, but I knew it wasn’t real. People are bad at Magic. Pros are much less bad at Magic, and would have been playing mirrors for weeks, and would get my decklist at the start of the match. There was no way this was going to work.

My last attempt was to wonder, what if Oko, Thief of Crowns was so targeted that we want to avoid that? I’d already thought about what I’d do if they banned him, so perhaps he as shadow banned due to all the copies of Noxious Grasp and the need for speed. What if we shifted blue to black and brought in everyone’s favorite Embercleave target, Rotting Regisaur?

Your new crazy draw is Arboreal Grazer into Rotting Regisaur into third turn fourth land plus Embercleave, attacking for 16. Combine that with all the Legion Warboss starts, and you have a lot of ways to come out super threatening.

You’d run it like this (at the time I hadn’t come around to Domri, Anarch of Bolas and Krenko, Tin Street Kingpin, so I was running more copies of Gruul Spellbreaker and Colossus instead):

7 Forest

5 Mountain

4 Stomping Ground

4 Blood Crypt

4 Overgrown Tomb

4 Once Upon a Time

4 Arboreal Grazer

4 Gilded Goose

4 Legion Warboss

4 Rotting Regisaur

1 Gruul Spellbreaker

3 Krenko, Tin Street Kingpin

4 Questing Beast

4 Embercleave

2 Collision // Colossus

2 Domri, Anarch of Bolas


4 Domri’s Ambush

4 Bonecrusher Giant

4 Lovestruck Beast

3 Veil of Summer

The mana does not support Noxious Grasp or discard spells, and you don’t want to trade cards anyway. Sorcerous Spyglass would be a sideboard consideration but it is very much against what the deck wants to do, so I’d be hesitant despite the rise of sacrifice decks. Domri’s Ambush trades cards, which should make you suspicious, but it is still exactly what you want in enough places that I believe it is justified, even if four copies is a lot. If I had something better, I’d be happy trimming some of them.

The big new specific issue with this approach is that Rotting Regisaur is very, very bad against Foulmire Knight and Calderon Familiar unless it picks up a sword, and can be stopped by Wicked Wolf as well. You’re paying a lot to get that card, and then often it ends up being bad. You’re also very all-in on the card when you have it, when it is liable to be turned into an Elk or bounced to your hand at the wrong time.

The big new general issue is that Oko, Thief of Crowns is a completely messed up Magic card, while Rotting Regisaur is a interesting but balanced and ultimately reasonable Magic card that can easily backfire. Your feeling of general flexibility and invincibility is out the window in the name of extra velocity and some positioning, plus the mana got even worse because there is no red/black temple. The deck gets more turn four and five kills, but also a ton more games where it does not operate properly.

So instead I played Jeskai Cavalier Fires. I had a bad draft (it is one draft, so hard to tell how much of that was my fault during the draft versus bad luck in positioning and what was opened), lost the coin flip in the mirror one round (the mirror is super dumb, both of us had draws which win 100% on the play, even against a stacked deck) and went 2-1-1 against Oko decks. Game one is still quite good there, even against pros, but games two and three are reasonably bad once they are on the ball and sideboard eleven cards. You can’t steal one reliably enough.

After Richmond, I was not happy. Then I thought about Domri, Anarch of Bolas again. Did I forget it was a thing because of the conflict with Lovestruck Beast? Was that even a conflict? Sure, the Lovestruck Beast can’t attack, but it can fight while everyone else attacks, and if they don’t kill Domri then are you really going to lose if you’re up against anything aggressive? The card does so much for you, perhaps we should try it. In particular, it works great with Krenko, as does Collision / Colossus, giving us dreams of a huge Goblin army, perhaps with two power. Perhaps we did not need the black after all?

Thus was born Goblin Blade, which I am now happier with than Dino Blade, especially with the rise of Witch’s Oven. We’re doing this now:

11 Forest

9 Mountain

4 Overgrown Tomb

4 Once Upon a Time

4 Arboreal Grazer

4 Gilded Goose

4 Legion Warboss

3 Gruul Spellbreaker

3 Krenko, Tin Street Kingpin

4 Questing Beast

4 Embercleave

3 Collision // Colossus

3 Domri, Anarch of Bolas


4 Domri’s Ambush

4 Bonecrusher Giant

4 Lovestruck Beast

3 Veil of Summer

This is a very clean build. If they can’t interact well with a red two toughness creature, you’re likely to unleash a large army of attackers on the third and fourth turns while continuing to otherwise play your game. You hit fast and you hit hard, going wide in a format where going wide is not the usual approach. You don’t especially care if any given creature is blocked, so Witch’s Oven is not an issue unless they have Mayhem Devil tricks backing it up.

One issue is that the Gruul deck has become an adventure deck with four Domri’s Ambush and four Bonecrusher Giant, which gives it a lot of ways to take out Legion Warboss and Krenko, Tin Street Kingpin. It also has four Kruul Harpooner, so Gilded Goose is likely toast as well. I have been less than thrilled with that matchup. Cavaliers is another future-Standard problem, as Deafening Clarion is exactly what you don’t want to be up against. You can make them have it, but these days ‘make them have it’ is not a good plan, because they always have it. If they didn’t have it, would they even have kept?

You also have all the obvious problems with Massacre Girl and other sweepers, with your plan being to put the game out of reach quickly enough to make that not an issue. But mostly this deck is a gamble that you won’t be facing such problems, and establishing a wide presence quickly will secure the game. We could easily spare a bunch of sideboard space, but I don’t see a good plan B in the offering – we could put in Skarrgan Hellkite or Sarkhan the Masterless or Shifting Ceratops or Biogenic Ooze or Ravager Wurm if we wanted to, but that does not seem like how we win matches.

Unfortunately our mana does not support Vivien, Arkbow Ranger. We no longer have enough food for Wicked Wolf.

I don’t think there is much to change in the main – you can change the number of Colossus to suit the situation, but either this set of cards works or it doesn’t, given that Lovestruck Beast is not where you want to be, and three toughness on Bonecrusher Giant also is not where I want to be given Clarion even if Nissa and Oko fade away. I haven’t tried Grumgully, the Generous but I doubt it’s good enough. Thrash // Threat is not impossible, but I think power levels have become too high for that approach.

The sideboard could consider Sorcerous Spyglass, and generally has plenty of room if we find worthwhile things. The issue is that you need the deck to stay mostly as it is, which is why we tune to find the right creatures rather than considering transformational or hate cards. Veil of Summer is the exception because it is too good not to play.

Will this be good enough in the new world? We don’t know. We don’t even know what the new world will ban. All I can report is that Goblin Blade is viable relatively high up the Mythic ladder, it is fun as hell, and it gets to play some messed up Magic cards to their fullest.



Evolution of Modularity

Новости LessWrong.com - 14 ноября, 2019 - 09:49
Published on November 14, 2019 6:49 AM UTC

This post is based on chapter 15 of Uri Alon’s book An Introduction to Systems Biology: Design Principles of Biological Circuits. See the book for more details and citations; see here for a review of most of the rest of the book.

Fun fact: biological systems are highly modular, at multiple different scales. This can be quantified and verified statistically, e.g. by mapping out protein networks and algorithmically partitioning them into parts, then comparing the connectivity of the parts. It can also be seen more qualitatively in everyday biological work: proteins have subunits which retain their function when fused to other proteins, receptor circuits can be swapped out to make bacteria follow different chemical gradients, manipulating specific genes can turn a fly’s antennae into legs, organs perform specific functions, etc, etc.

On the other hand, systems designed by genetic algorithms (aka simulated evolution) are decidedly not modular. This can also be quantified and verified statistically. Qualitatively, examining the outputs of genetic algorithms confirms the statistics: they’re a mess.

So: what is the difference between real-world biological evolution vs typical genetic algorithms, which leads one to produce modular designs and the other to produce non-modular designs?

Kashtan & Alon tackle the problem by evolving logic circuits under various conditions. They confirm that simply optimizing the circuit to compute a particular function, with random inputs used for selection, results in highly non-modular circuits. However, they are able to obtain modular circuits using “modularly varying goals” (MVG).

The idea is to change the reward function every so often (the authors switch it out every 20 generations). Of course, if we just use completely random reward functions, then evolution doesn’t learn anything. Instead, we use “modularly varying” goal functions: we only swap one or two little pieces in the (modular) objective function. An example from the book:

The upshot is that our different goal functions generally use similar sub-functions - suggesting that they share sub-goals for evolution to learn. Sure enough, circuits evolved using MVG have modular structure, reflecting the modular structure of the goals.

(Interestingly, MVG also dramatically accelerates evolution - circuits reach a given performance level much faster under MVG than under a fixed goal, despite needing to change behavior every 20 generations. See either the book or the paper for more on that.)

How realistic is MVG as a model for biological evolution? I haven’t seen quantitative evidence, but qualitative evidence is easy to spot. MVG as a theory of biological modularity predicts that highly variable subgoals will result in modular structure, whereas static subgoals will result in a non-modular mess. Alon’s book gives several examples:

  • Chemotaxis: different bacteria need to pursue/avoid different chemicals, with different computational needs and different speed/energy trade-offs, in various combinations. The result is modularity: separate components for sensing, processing and motion.
  • Animals need to breathe, eat, move, and reproduce. A new environment might have different food or require different motions, independent of respiration or reproduction - or vice versa. Since these requirements vary more-or-less independently in the environment, animals evolve modular systems to deal with them: digestive tract, lungs, etc.
  • Ribosomes, as an anti-example: the functional requirements of a ribosome hardly vary at all, so they end up non-modular. They have pieces, but most pieces do not have an obvious distinct function.

To sum it up: modularity in the system evolves to match modularity in the environment.


Autism And Intelligence: Much More Than You Wanted To Know

Новости LessWrong.com - 14 ноября, 2019 - 08:30
Published on November 14, 2019 5:30 AM UTC

[Thanks to Marco G for proofreading and offering suggestions]


Several studies have shown a genetic link between autism and intelligence; genes that contribute to autism risk also contribute to high IQ. But studies show autistic people generally have lower intelligence than neurotypical controls, often much lower. What is going on?

First, the studies. This study from UK Biobank finds a genetic correlation between genetic risk for autism and educational attainment (r = 0.34), and between autism and verbal-numerical reasoning (r = 0.19). This study of three large birth cohorts finds a correlation between genetic risk for autism and cognitive ability (beta = 0.07). This study of 45,000 Danes finds that genetic risk for autism correlates at about 0.2 with both IQ and educational attainment. These are just three randomly-selected studies; there are too many to be worth listing.

The relatives of autistic people will usually have many of the genes for autism, but not be autistic themselves. If genes for autism (without autism itself) increase intelligence, we should expect these people to be unusually smart. This is what we find; see Table 4 here. Of 11 types of psychiatric condition, only autism was associated with increased intelligence among relatives. This intelligence is shifted towards technical subjects. About 13% of autistic children have fathers who are engineers, compared to only 5% of a group of control children (though see the discussion here) for some debate over how seriously to take this; I am less sure this is accurate than most of the other statistics mentioned here).

Further (indirect) confirmation of the autism-IQ link comes from evolutionary investigations. If autism makes people less likely to reproduce, why would autism risk genes stick around in the human population? Polimanti and Gelemter (2017) find that autism risk genes aren’t just sticking around. They are being positively selected, ie increasing with every generation, presumably because people with the genes are having more children than people without them. This means autism risk genes must be doing something good. Like everyone else, they find autism risk genes are positively correlated with years of schooling completed, college completion, and IQ. They propose that the reason evolution favors autism genes is that they generally increase intelligence.

But as mentioned before, autistic people themselves generally have very low intelligence. One study found that 69% of autistic people had an IQ below 85 (the average IQ of a high school dropout). Only 3% of autistic people were found to have IQs above 115, even though 15% of the population should be at this level.

These numbers should be taken with very many grains of salt. First, IQ tests don’t do a great job of measuring autistic people. Their intelligence tends to be more imbalanced than neurotypicals’, so IQ tests (which rely on an assumption that most forms of intelligence are correlated) are less applicable. Second, even if the test itself is good, autistic people may be bad at test-taking for other reasons – for example, they don’t understand the directions, or they’re anxious about the social interaction required to answer an examiner’s quetsions. Third, and most important, there is a strong selection bias in the samples of autistic people. Many definitions of autism center around forms of poor functioning which are correlated with low intelligence. Even if the definition is good, people who function poorly are more likely to seek out (or be coerced into) psychiatric treatment, and so are more likely to be identified. In some sense, all “autism has such-and-such characteristics” studies are studying the way people like to define autism, and tell us nothing about any underlying disease process. I talk more about this in parts 2 and 3 here.

But even adjusting for these factors, the autism – low intelligence correlation seems too strong to dismiss. For one thing, the same studies that found that relatives of autistic patients had higher IQs find that the autistic patients themselves have much lower ones. The existence of a well-defined subset of low IQ people whose relatives have higher-than-predicted IQs is a surprising finding that cuts through the measurement difficulties and suggests that this is a real phenomenon.

So what is going on here?


At least part of the story is that there are at least three different causes of autism.

1. The “familial” genes mentioned above: common genes that increase IQ and that evolution positively selects for.

2. Rare “de novo mutations”, ie the autistic child gets a new mutation that their non-autistic parent doesn’t have. These mutations are often very bad, and are quickly selected out of the gene pool (because the people who have them don’t reproduce). But “quickly selected out of the gene pool” doesn’t help the individual person who got one of them, who tends to end up severely disabled. In a few cases, the parent gets the de novo mutation, but for whatever reason doesn’t develop autism, and then passes it onto their child, who does develop autism.

3. Non-genetic factors. The best-studied are probably obstetric complications, eg a baby gets stuck in the birth canal and can’t breathe for a long time. Pollution, infection, and trauma might also be in this basket.

These three buckets and a few other less important factors combine to determine autism risk for any individual. Combining information from a wide variety of studies, Gaugler et al estimate that about 52% of autism risk is attributable to ordinary “familial” genes, 3% to rare “de novo” mutations, 4% to complicated non-additive genetic interaction effects, and 41% “unaccounted”, which may be non-genetic factors or genetic factors we don’t understand and can’t measure. This study finds lower heritability than the usual estimates (which are around 80% to 90%; the authors are embarrassed by this, and in a later study suggest they might just have been bad at determining who in their sample did or didn’t have autism. While their exact numbers are doubtful, I think the overall finding that common familial genes are much more important than rare de novo mutations survives and is important.

Most cases of autism involve all three of these factors; that is, your overall autisticness is a combination of your familial genes, mutations, and environmental risk factors.

One way of resolving the autism-intelligence paradox is to say that familial genes for autism increase IQ, but de novo mutations and environmental insults decrease IQ. This is common-sensically true and matches previous research into all of these factors. So the only question is whether the size of the effect is enough to fully explain the data – or whether, even after adjusting out the degree to which autism is caused by mutations and environment, it still decreases IQ.

Ronemus et al (2014) evaluate this:

They find that even autistic people without de novo mutations have lower-than-average IQ. But they can only screen for de novo mutations they know about, and it could be that they just missed some.

Here’s another set of relevant graphs:

This one comes from Gardner et al (2019), which measures the cognitive ability of the fathers of autistic people and disaggregates those with and without intellectual disability. In Graph A, we see that if a child has autism (but not intellectual disability), their likelihood of having a father with any particular IQ (orange line) is almost the same as the likelihood of a neurotypical child having a father of that IQ (dotted line). Disguised in that “almost” is a very slight tendency for fathers to be unusually intelligent, plus a (statistically insignificant) tendency for them to be unusually unintelligent. For reasons that don’t entirely make sense to me, if instead we look at the likelihood of the father to be a certain intelligence (bottom graph, where dark line surrounded by gray confidence cloud is autistic people’s fathers, and dotted line is neurotypical people’s fathers) it becomes more obvious that more intelligent people are actually a little more likely to have autistic children (though less intelligent people are also more likely.

(remember that “intellectual disability” just means “IQ over 70”, and so many of these not-intellectually-disabled people may be very intellectually weak – I wish the paper had quantified this)

Graph B is the same thing, but with people have have autism with intellectual disability. Now there is a very strong effect towards their fathers being less intelligent than usual.

This confuses me a little. But for me the key point is that high-intelligence fathers show a trend (albeit not significant in this study) to be more likely than average to have children with autism and intellectual disability.

These questions interest me because I know a lot of people who are bright nerdy programmers married to other bright nerdy programmers, and sometimes they ask me if their children are at higher risk for autism. While their children are clearly at higher risk for autistic traits, I think they want to know whether they have higher risk for the most severe forms of the syndrome, including intellectual disability and poor functioning. If we take the Ronemus and Gardner studies seriously, the answer seems to be yes. The Gardner study seems to suggest it’s a very weakly elevated risk, maybe only 1.1x or 1.2x relative risk. But the Gardner study also ceilings off at 90th percentile intelligence, so at this point I’m not sure what to tell these people.


If Ronemus isn’t missing some obscure de novo mutations, then people who get autism solely by accumulation of common (usually IQ-promoting) variants still end up less intelligent than average. This should be surprising; why would too many intelligence-promoting variants cause a syndrome marked by low intelligence? And how come it’s so inconsistent, and many people have naturally high intelligence but aren’t autistic at all?

One possibility would be something like a tower-vs-foundation model. The tower of intelligence needs to be built upon some kind of mysterious foundation. The taller the tower, the stronger the foundation has to be. If the foundation isn’t strong enough for the tower, the system fails, you develop autism, and you get a collection of symptoms possibly including low intelligence. This would explain low-functioning autism from de novo mutations or obstetric trauma (the foundation is so weak that it fails no matter how short the tower is). It would explain the association of genes for intelligence with autism (holding foundation strength constant, the taller the tower, the more likely a failure). And it would also explain why there are many extremely intelligent people who don’t have autism at all (you can build arbitrarily tall towers if your foundation is strong enough).

I’ve only found one paper that takes this model completely seriously and begins speculating on the nature of the foundation. This is Crespi 2016, Autism As A Disorder Of High Intelligence. It draws on the VPR model of intelligence, where g (“general intelligence”) is divided into three subtraits, v (“verbal intelligence”), p (“perceptual intelligence”), and r (“mental rotation ability”) – despite the very specific names each of these represents ability at broad categories of cognitive tasks. Crespi suggests that autism is marked by an imbalance between P (as the tower) and V + R (as the foundation). In other words, if your perceptual intelligence is much higher than your other types of intelligence, you will end up autistic.

It doesn’t really present much evidence for this other than that autistic people seem to have high perceptual intelligence. Also, it doesn’t really look like autistic people are worse at mental rotation. Also, the Gardner paper has analyzed autistic patients’ fathers by subtype of intelligence, and there is a nonsignificant but pretty suggestive tendency for them to have higher-than-normal verbal intelligence; certainly no signs of high verbal intelligence preventing autism. I can’t tell if this is evidence against Crespi or whether since all intellectual abilities are correlated this is just the shadow of their high perceptual intelligence, and if we directly looked at perceptual-to-verbal ratio we would see it was lower than expected. Also also, Crespi is one of those scientists who constantly has much more interesting theories than anyone else (eg), and this makes me suspicious.

Overall I would be surprised if this were the real explanation for the autism-and-intelligence paradox, but it gets an A for effort.


1. The genes that increase risk of autism are disproportionately also genes that increase intelligence, and vice versa (~100% confidence)

2. People diagnosed with autism are less intelligent than average (~100% confidence, leaving aside definitional complications)

3. Some of this effect is because autism is caused both by normal genes and by de novo mutations and environmental insults, and the de novo mutations and environmental insults definitely decrease intelligence. Every autism case is caused by some combination of these three factors, and the more it is caused by normal genes, the more intelligence is likely to be preserved (~100% confidence)

4. This is not the whole story, and even cases of autism that are caused entirely or mostly by normal genetics are associated with unusually low IQ (80% confidence)

5. This can best be understood through a tower-versus-foundation model where higher intelligence that outstrips the ability of some mysterious foundation to support it will result in autism (25% confidence)

6. The specific way the model plays out may be through perceptual intelligence out of balance with verbal and rotational intelligence causing autism (3% confidence)


[Link] John Carmack working on AGI

Новости LessWrong.com - 14 ноября, 2019 - 03:08
Published on November 14, 2019 12:08 AM UTC

John Carmack, confirmed GOAT video game developer, is going to take a crack at AGI.



[Link] (EA Podcast) Social Status: The Key to the Matrix Part I

Новости LessWrong.com - 14 ноября, 2019 - 01:53
Published on November 13, 2019 9:09 PM UTC

A new episode of Global Optimum has been released! Global Optimum is a podcast aimed at making altruists more effective. This episode is about the psychology of social status. The desire for status is a fundamental human motive. Understanding status can help us understand many otherwise puzzling features of our world. In this episode, I apply our understanding of status psychology to analyze various dynamics and trends within effective altruism.

This episode features:

-How do people behave differently when they are high vs low status?

-How did human social status evolve?

-Should you try to dampen your desire for status?

-Are EAs too credential-focused?

-Is publishing in academic journals overrated?

-Can you get more done by working alone than by starting an organization?

-What causes groups to splinter?

-How has effective altruism “professionalized?” What are the upsides and downsides of this trend?

Full transcript

The podcast is available on all podcast apps.

Listen here


Instant stone (just add water!)

Новости LessWrong.com - 14 ноября, 2019 - 01:33
Published on November 13, 2019 10:33 PM UTC

Originally posted on The Roots of Progress, January 6, 2018

From the time that humans began to leave their nomadic ways and live in settled societies about ten thousand years ago, we have needed to build structures: to shelter ourselves, to store our goods, to honor the gods.

The easiest way to build is with dirt. Mud, clay, any kind of earth. Pile it up and you have walls. A few walls and a thatched roof, and you have a hut.

Earthen hut with thatched roof in Sudan - Petr Adam Dohnálek / Wikimedia

But earthen construction has many shortcomings. Dirt isn’t very strong, so you can’t build very high or add multiple stories. It tends to wash away in the rain, so it really only works in hot, dry climates. And it can be burrowed through by intruders—animal or human.

We need something tougher. A material that is hard and strong enough to weather any storm, to build high walls and ceilings, to protect us from the elements and from attackers.

Stone would be ideal. It is tough enough for the job, and rocks are plentiful in nature. But like everything else in nature, we find them in an inconvenient form. Rocks don’t come in the shape of houses, let alone temples. We could maybe pile or stack them up, if only we had something to hold them together.

If only we could—bear with me now as I indulge in the wildest fantasy—pour liquid stone into molds, to create rocks in any shape we want! Or—as long as I’m dreaming—what if we had a glue that was as strong as stone, to stick smaller rocks together into walls, floors and ceilings?

This miracle, of course, exists. Indeed, it may be the oldest craft known to mankind. You already know it—and you probably think of it as one of the dullest, most boring substances imaginable.

I am here to convince you that it is pure magic and that we should look on it with awe.

It’s called cement.

Let’s begin at the beginning. Limestone is a soft, light-colored rock with a grainy texture, which fizzes in the presence of acid. Chalk is a form of limestone. What distinguishes limestone and makes it useful is a high calcium content (“calcium” and “chalk” are cognates). Specifically, it is calcium carbonate (CaCO3), the same substance that makes up seashells. In fact, limestone, a sedimentary rock, is often formed from crushed seashells, compressed over eons.

Limestone from a quarry in southern Germany - Hannes Grobe / Wikimedia

Limestone can be used for many purposes, including fertilizer and whitewash, but its most important industrial use is in making cement. When it is heated to about 1,000 °C (e.g., in a kiln), it produces a powder called quicklime. Chemically, what’s going on is that burning calcium carbonate removes carbon dioxide and leaves calcium oxide (CaCO3 + heat → CaO + CO2).

Quicklime is a caustic substance: touching it will burn your skin (hence “quick”, meaning active, “alive”). But perhaps its strangest property is that when mixed with water, it reacts, giving off heat—enough to boil the water! The result, called “slaked” or “hydrated” lime, is calcium hydroxide (CaO + H2O → Ca(OH)2 + heat).

Further, if you pour a lime-water slurry into a mold, not too thick, and expose it to the air, a still more amazing thing happens: in a matter of hours, the mixture “sets” and becomes once again as hard as stone. The calcium hydroxide has absorbed CO2 from the air to return to calcium carbonate (Ca(OH)2 + CO2 → CaCO3 + H2O), completing what is known as the “lime cycle”.

In other words, by mixing with water and air, this powder—a basic cement—has turned back into rock! If this technology hadn’t already existed since before recorded history, it would seem futuristic.

The product of a pure lime cement is too brittle and weak to be very useful (except maybe as a grout). But we can make it stronger by mixing in sand, gravel or pebbles, called “aggregate”. Cement, water and sand produce mortar, a glue that can hold together bricks or stones in a masonry wall. Adding gravel or pebbles as well will make concrete, which can be poured into molds to set in place. (The terms “cement” and “concrete” are often conflated, but technically, cement is the powder from which mortar and concrete are made; concrete is the substance made by adding aggregate and is what constitutes sidewalks, buildings, etc.)

Brick wall with cement mortarConcrete wall with aggregate visible

This basic technology has been known since prehistoric times: the kilning of limestone is older than pottery, much older than metalworking, and possibly older than agriculture. But over the millenia, better formulas for cement have been created, with superior mixtures of ingredients and improved processes.

Pure lime cement needs air to set, so it can’t set if poured too thick, or underwater (for instance, on a riverbed to form the base of a column for a bridge). The Romans, who were great users of cement, discovered that adding volcanic ash, called pozzalana, to lime would produce a cement that sets even underwater; this is called a “hydraulic cement”. They used this “Roman cement” to build everything from aqueducts to the Colosseum. Another common hydraulic cement, called “natural cement”, is formed from a mixture of limestone and clay, which sometimes occur together in natural deposits.

Since the mid-1800s, the most widely used cement is a type called Portland cement. Without going into too much detail, this is made through an unintuitive process that involves heating a lime-clay slurry to the point where it fuses together into a hard substance called “clinker”. Clinker was originally considered waste material, a ruined product—until it was discovered that grinding it into powder produced a cement that is stronger than Roman or natural cement. (!) Today a wide variety of cements are available on the market, optimized for different conditions.

No matter the formula, however, all cements have one shortcoming: they are very strong under compression, which is the kind of strength needed in a column or wall, but weak under tension, which comes into play, for instance, when a beam buckles under load. The Romans dealt with this problem using arches, which direct forces into compression along the arch. Medieval builders created the pointed Gothic arch, which could stretch even higher than the round Roman ones, and the flying buttress, which added support to the walls of their tall cathedrals.

Pont du Gard, a Roman aqueduct bridge near Nîmes, FranceGothic window, Church of St. Helen, Lincolnshire, England - Spencer Means / Flickr


But in the twentieth century, a new way of building took over: reinforcing the concrete with steel. Steel, unlike concrete, has high tensile strength, so this “reinforced concrete” is strong under both compression and tension. The reinforcement bars created for this purpose are called “rebar.” Reinforcement allows concrete to be used not only for foundations, walls and columns, but for cantilevered structures such as the decks of Fallingwater.

Fallingwater, by Frank Lloyd Wright - Mathieu Thouvenin / Flickr

This is cement. We start with rock, crush and burn it to extract its essence in powdered form, and then reconstitute it at a place and time and in a shape of our choosing. Like coffee or pancake mix, it is “instant stone—just add water!” And with it, we make skyscrapers that reach hundreds of stories high, tunnels that go under the English channel and the Swiss Alps, and bridges that stretch a hundred miles.

If that isn’t magic, I don’t know what is.

Sources and further reading: Concrete Planet: The Strange and Fascinating Story of the World’s Most Common Man-Made Material, Geology.com, Minerals Education Coalition, Portland Cement Association, and many pages on Wikipedia. Thanks also to Doug Peltz of Mystery Science for helpful conversations.



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