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Austerity is Inefficient

Working on an emergency timetable for regional rail has made it clear how an environment of austerity requires tradeoffs that reduce efficiency. I already talked about how the Swiss electronics before concrete slogan is not about not spending money but about spending a fixed amount of money intelligently; but now I have a concrete example […]

via Pedestrian Observations February 27, 2021

Fireside Friday, February 26, 2021

Fireside this week, but next week we are diving into our long awaited series on pre-modern textile production, though we will be particularly focused on the most important clothing fibers in the Mediterranean world, wool and linen (rather than, say, silk or cotton). For this week’s musing, I want to expand on an issue that … Continue reading Fireside Friday, February 26, 2021 →

via A Collection of Unmitigated Pedantry February 26, 2021

Cut-and-Cover is Underrated

Subways can be built in two ways: cut-and-cover, and bored tunnel. Cut-and-cover means opening up the street top-down, building the system, and roofing it to restore surface traffic; bored tunnel means opening up one portal and digging horizontally, with less surface disturbance. In the last generation or two there has been a shift toward bored […]

via Pedestrian Observations February 26, 2021

Pulses (Hoisted from Comments)

Robert Jackel asked me an excellent question in comments: what is a pulse? I’ve talked about timed transfers a lot in the last almost 10 years of this blog, but I never wrote a precise definition. This is a critical tool for every public transportation operation with more than one line, making sure that trains […]

via Pedestrian Observations February 23, 2021

Density and Rail Transport (Hoisted from Social Media)

I wrote a long thread about regional rail and population density, and I’d like to explain more and give more context. The upshot is that higher population density makes it easier to run a rail network, but the effects are most visible for regional rail, rather than either urban rail or high-speed intercity rail. This […]

via Pedestrian Observations February 21, 2021

Collections: The Universal Warrior, Part III: The Cult of the Badass

This is the third and final part of a discussion (I, IIa, IIb) discussion of the notion that there is a ‘universal warrior’ – a transcendent sameness about either the experience of war or ‘warrior values’ which might provide some sort of useful blueprint for life generally or some sort of fundamental truth about the … Continue reading Collections: The Universal Warrior, Part III: The Cult of the Badass →

via A Collection of Unmitigated Pedantry February 19, 2021

How to Get Rich Off Low Construction Costs

A country or region that is good at manufacturing cars can export them globally and earn hard cash. But what about public transportation? How can a city that has the ability to build good, low-cost public transport get rich off of it? There is an answer, but it is more complicated than “export this,” mirroring […]

via Pedestrian Observations February 18, 2021

The Troubling Ethics of Writing (A Speech from Ancient Sumer)

(Translated from a transcript of an ancient Sumerian speech by Uruk's most well-respected Scriptological Ethicist) Writing is a profoundly dangerous technology: Access to writing was initially, and still remains, uneven. What's worse, the rich are more likely to be literate, so it not only creates inequalities but exacerbates existing ones. Written language embodies the biases and prejudices of the people responsible for writing. Writing makes those prejudices more permanent and influentia…

via BLOG - Cullen O'Keefe February 15, 2021

Gift ideas for preschool / early elementary children

Previously: gift ideas for young children (0-2) I thought I’d list some toys our kids have especially liked. None of these are amazing revelations that you probably couldn’t find on other sites. I’m picking things that need little or no adult supervision, unless otherwise specified. A few of these (especially the Melissa and Doug toys) […]

via The whole sky February 14, 2021

Collections: The Universal Warrior, Part IIb: A Soldier’s Lot

This is the continuation of the second part of a three part (I, IIa, III) discussion of the notion that there is a ‘universal warrior’ – a transcendent sameness about either the experience of war or ‘warrior values’ which might provide some sort of useful blueprint for life generally or some sort of fundamental truth … Continue reading Collections: The Universal Warrior, Part IIb: A Soldier’s Lot →

via A Collection of Unmitigated Pedantry February 12, 2021

Blameworthiness for Avoidable Psychological Harms

When a harm is created as a result of both external actions and a psychological reaction, how should we apportion blame?

via BLOG - Cullen O'Keefe February 9, 2021

Collections: The Universal Warrior, Part IIa: The Many Faces of Battle

This is the second part of a three part (I, II) discussion of the idea of a ‘universal warrior’ – the assumption that there is a transcendent sameness about either the experience of war or ‘warrior values’ which might provide some sort of fundamental truth for understanding war, either in the past or present, or … Continue reading Collections: The Universal Warrior, Part IIa: The Many Faces of Battle →

via A Collection of Unmitigated Pedantry February 5, 2021

Collections: The Universal Warrior, Part I: Soldiers, Warriors, and…

This is the first part of a three part (II, III) discussion of an idea I am going to term (borrowing from one of its proponents) the ‘universal warrior’ – the idea that there is a transcendent sameness about either the warrior experience or warrior values which provides some sort of useful blueprint for today … Continue reading Collections: The Universal Warrior, Part I: Soldiers, Warriors, and… →

via A Collection of Unmitigated Pedantry January 29, 2021


Today I made valentines. I made fruit valentines. There were orange fruit valentines, and grape fruit valentines, watermelon fruit valentines, and pineapple too. I made them for my classmates and teacher. They had a little jokes or puns on the back. The jokes or puns were on a sticker that we could stick on the back. I stuck on googly eyes, and I drew a mouth. I added hearts and a sticker. That's how I made the valentines. Here is a picture so you can see some of my valentines:

via Lily Wise's Blog Posts January 23, 2021

You can make maple syrup in a slow cooker

I tried to find out if anyone had successfully done this, and couldn’t find verification on the internet. So this is just to confirm: yes, you can boil maple sap into syrup in a slow cooker / crock pot. This is my third year doing it. I’m not sure if the cost of the electricity […]

via The whole sky January 15, 2021

My 2020 Giving

2020 Giving in ContextIn 2020, I donated $ 24,918.01. By organization, these were:Legal Priorities Project: $ 10,005.50Long-Term Future EA Fund: $ 8,036.00Joe Biden for President: $ 2,800GiveWell (regrant): $ 1,551Center for Election Science: $ 1,000Charter Cities Institute: $ 1,000EA Cameroon: $ 250Against Malaria Foundation: $ 120GiveDirectly: $ 83.51Malaria Consortium: $ 30Nuclear Threat Initiative: $ 22Wild Animal Initiative: $ 10MIRI: $ 10This does not include donations made on my behalf a…

via BLOG - Cullen O'Keefe January 5, 2021

Who benefits from the au pair program?

I’m writing this post from more of an economics-y perspective than usual. I used to be super suspicious of this approach because I read it as cold and selfish. I hope you’ll take me in good faith here as caring about au pairs, about people who could become au pairs if they were allowed to, […]

via The whole sky January 4, 2021

Systems design explains the world: volume 1

"Systems design" is a branch of study that tries to find universal architectural patterns that are valid across disciplines. You might think that's not a possibility. Back in university, students used to tease the Systems Design Engineers, calling it "boxes and arrows" engineering. Not real engineering, you see, since it didn't touch anything tangible, like buildings, motors, hydrochloric acid, or, uh, electrons. I don't think the Systems Design people took this critici…

via apenwarr December 29, 2020

Against essential and accidental complexity

In the classic 1986 essay, No Silver Bullet, Fred Brooks argued that there is, in some sense, not that much that can be done to improve programmer productivity. His line of reasoning is that programming tasks contain a core of essential/conceptual1 complexity that's fundamentally not amenable to attack by any potential advances in technology (such as languages or tooling). He then uses an Ahmdahl's law argument, saying that because 1/X of complexity is essential, it's impossible to …

via Posts on Dan Luu December 29, 2020

Thoughts you mightn't'a thunk about remote meetings

Welcome to this week's edition of "building a startup in 2020," in which all your meetings are suddenly remote, and you probably weren't prepared for it. I know I wasn't. We started a "fully remote" company back in 2019, but that was supposed to mean we still got together in person every month or two to do strategic planning, share meals, and resolve any accumulated conflicts. Well, not this year. Instead, we had to learn to have better remote meetings, all while build…

via apenwarr December 27, 2020

Milk Experiments

I mixed milk with some colored pigment. First, the color spread a little tiny bit. And then when we added we added some dish soap the colors spread and a big colorful wave.

via Lily Wise's Blog Posts December 27, 2020

Media I Liked: Q4 2020

Inspired by Luke Muehlhauser, I'm going to try to start using my blog to highlight some media I've enjoyed over the past ~quarter. Since this is my first post, this contains some stuff especially I liked in Q3 as well. Music Will Wood, The Normal Album (2020) ミラクルミュージカル, Hawaii: Part II (2012) Lots of stuff by Billy Cobb, especially: Zerwee (2020) Zerwee, Pt. 2 (2020) Rocky Horror, on Strokes of Incarceration (2018) Lots of stuff by Beach Bunny, especially: Prom Queen, on Prom Queen (2…

via BLOG - Cullen O'Keefe December 26, 2020

My favorite essays of life advice

Life is short • There is no speed limit • How to Be Successful • You and your research • Becoming a Magician • 95th percentile isn’t that good

via December 23, 2020

To listen well, get curious

When I’ve listened the most effectively to people, it’s because I was intensely curious—I was trying to build a detailed, precise understanding of what was going on in their head.

via December 12, 2020

In defense of blub studies

Why it’s worth it to deeply understand the fiddly, boring-seeming details of the computer systems you use every day.

via December 5, 2020

My Giving Tuesday 2020 Plans

$1,000 to the Charter Cities Institute $1,000 to the Center for Election Science $10,000 to the Legal Priorities Project Approximately $8,000 to the EA Long-Term Future Fund

via BLOG - Cullen O'Keefe November 25, 2020

Can I work for a bad company and still be a good person?


via apenwarr November 23, 2020

It’s not economically inefficient for a UBI to reduce recipient’s employment

A UBI (e.g. paying every adult American $8k/year) would reduce recipient’s need for money and so may reduce their incentive to work. This is frequently offered as an argument against a UBI (or as an argument for alternative policies like the EITC that directly incentivize work). This argument is sometimes presented as economically hard-headed realism. … More It’s not economically inefficient for a UBI to reduce recipient’s employment

via The sideways view November 22, 2020

Children’s podcast recommendations

I’ve emailed my list to enough friends that I should really just post it. Podcasts have been a big part of Lily’s life since around age 4. Before that, she spent a lot of her time demanding of any available adult, “READ. READ TO ME” (once she literally asked the cat, who did not read […]

via The whole sky October 11, 2020

Review of two Rhiannon Giddens songs

I listened to the “Folk Songs” album from Kronos Quartet, partly because of the two Rhiannon Giddens songs. I was interested to know the backstory on her songs, but I got annoyed by reading reviews of these songs that seemed to miss critical pieces. The only review I could find of “Lullaby” called it “sprightly”, […]

via The whole sky October 11, 2020

How to make video calls almost as good as face-to-face

I spent way too long figuring out the how to make video calls feel natural. Here’s the best advice I came up with.

via September 27, 2020

Distributed public goods provision

Most people benefit significantly from privately funded public goods (e.g. Wikipedia). If we all contribute to such public goods, then we can all end up better off. But as an individual it’s almost never a good return on investment. I think of supporting such public goods as being a good citizen, but that leaves open … More Distributed public goods provision

via The sideways view September 26, 2020

Learning Game

I came up with this game. In the game one person thinks of something and then gives the other person a clue. And the other person writes a guess down on a blackboard or a piece of paper. Or really anything you have that's laying around that's available for writing on. The other person says whether it's right or wrong. And then when they get it right the other person takes a turn. When they get it wrong the other person gives them another clue and they guess again. It has to be clos…

via Lily Wise's Blog Posts September 17, 2020


This is jewelry I made, but I didn't really make all of them. My au pair Erika made a few of them but I made most of them. I made at least six of them. Erika made two. Free delivery within a half hour bike ride of West Somerville. Otherwise I will send it to you in the mail. You pay for shipping. Email my dad, Jeff ( if you want to buy something. Butterfly Bracelet It costs $8. I was thinking about butterflies when I made this bracelet. Pom-pom Bracelet I was thinking about pom-p…

via Lily Wise's Blog Posts August 27, 2020

Pony Podcast

For kids one to ten. I might add some other episodes later. Part 1 Part 2 Part 3

via Lily Wise's Blog Posts August 18, 2020

Tools for keeping focused

no badges • close slack • check email 1x/day • keep todos visible • use rss • kindle + rss • hide phone apps • block ui elements • block sites • better window switcher • no tabs

via August 4, 2020

IPv4, IPv6, and a sudden change in attitude

A few years ago I wrote The World in Which IPv6 was a Good Design. I'm still proud of that article, but I thought I should update it a bit. No, I'm not switching sides. IPv6 is just as far away from universal adoption, or being a "good design" for our world, as it was three years ago. But since then I co-founded a company that turned out to be accidentally based on the principles I outlined in that article. Or rather, from turning those principles upside-down. In that article, I exp…

via apenwarr July 22, 2020

How do cars fare in crash tests they're not specifically optimized for?

Any time you have a benchmark that gets taken seriously, some people will start gaming the benchmark. Some famous examples in computing are the CPU benchmark specfp and video game benchmarks. With specfp, Sun managed to increase its score on (a sub-benchmark of specfp) by 12x with a compiler tweak that essentially re-wrote the benchmark kernel, which increased the Sun UltraSPARC’s overall specfp score by 20%. At times, GPU vendors have added specialized benchmark-detecting code to their…

via Posts on Dan Luu June 30, 2020

A simple way to get more value from tracing

A lot of people seem to think that distributed tracing isn't useful, or at least not without extreme effort that isn't worth it for companies smaller than FB. For example, here are a couple of public conversations that sound like a number of private conversations I've had. Sure, there's value somewhere, but it costs too much to unlock. I think this overestimates how much work it is to get a lot of value from tracing. At Twitter, Rebecca Isaacs was able to lay out a vision for how…

via Posts on Dan Luu May 31, 2020

A simple way to get more value from metrics

We spent one day1 building a system that immediately found a mid 7 figure optimization (which ended up shipping). In the first year, we shipped mid 8 figures per year worth of cost savings as a result. The key feature this system introduces is the ability to query metrics data across all hosts and all services and over any period of time (since inception), so we've called it LongTermMetrics (LTM) internally since I like boring, descriptive, names. This got started when I was looking for a st…

via Posts on Dan Luu May 30, 2020

Several grumpy opinions about remote work at Tailscale

As a "fully remote work" company, we had to make some choices about the technologies we use to work together and stay in touch. We decided early on - about the time we realized all three cofounders live in different cities - that we were going to go all-in on remote work, at least for engineering, which for now is almost all our work. As several people have pointed out before, fully remote is generally more stable than partly remote. In a partially remote team, the remote workers seem to …

via apenwarr March 11, 2020

How (some) good corporate engineering blogs are written

I've been comparing notes with people who run corporate engineering blogs and one thing that I think is curious is that it's pretty common for my personal blog to get more traffic than the entire corp eng blog for a company with a nine to ten figure valuation and it's not uncommon for my blog to get an order of magnitude more traffic. I think this is odd because tech companies in that class often have hundreds to thousands of employees. They're overwhelmingly likely to be better …

via Posts on Dan Luu March 11, 2020

It's ok to feed stray cats

Before we had kids, Jeff and I fostered a couple of cats. One had feline AIDS and was very skinny. Despite our frugal grocery budget of the time, I put olive oil on her food, determined to get her healthier. I knew that stray cats were not a top global priority, and that this wasn’t even the best way of helping stray cats, but it was what I wanted to do.. . . . .The bike path near where I live has a lot of broken glass on the ground nearby. My family likes to go barefoot in the summer, and a lo…

via Giving Gladly January 27, 2020

Hedonic asymmetries

Creating really good outcomes for humanity seems hard. We get bored. If we don’t get bored, we still don’t like the idea of joy without variety. And joyful experiences only seems good if they are real and meaningful (in some sense we can’t easily pin down). And so on. On the flip side, creating really … More Hedonic asymmetries

via The sideways view January 26, 2020

Moral public goods

Suppose that a kingdom contains a million peasants and a thousand nobles, and: Each noble makes as much as 10,000 peasants put together, such that collectively the nobles get 90% of the income. Each noble cares about as much about themselves as they do about all peasants put together. Each person’s welfare is logarithmic in … More Moral public goods

via The sideways view January 26, 2020

Prediction markets for internet points?

Using real money in prediction markets is all-but-illegal, and dealing with payments is a pain. But using fake money in prediction markets seems tricky, because by default players have no skin in the game. Here’s a simple proposal that I think might work reasonably well without being too hard to try: Create a service that … More Prediction markets for internet points?

via The sideways view October 27, 2019

You have more than one goal, and that's fine

When people come to an effective altruism event for the first time, the conversation often turns to projects they’re pursuing or charities they donate to. They often have a sense of nervousness around this, a feeling that the harsh light of cost-effectiveness is about to be turned on everything they do. To be fair, this is a reasonable thing to be apprehensive about, because many youngish people in EA do in fact have this idea that everything in life should be governed by cost-effectiveness. I&…

via Giving Gladly February 19, 2019

No one is a statistic

I’m late to the party, but I've been thinking about the documentary “The Life Equation” about how people use data to decide make life-and-death decisions. The central example is a woman named Crecencia, a mother of seven who lives in rural Guatemala and has cervical cancer. The doctor treating her knows that screening other women for cancer is more cost-effective than treating this woman, and that the community doesn’t have enough money to fully fund both. The filmmaker writes: “Crecencia’s…

via Giving Gladly October 10, 2018

Two standard donations and one new one

Here are three places Jeff and I are donating this year. The first two are similar to what we’ve been doing for years, and the third represents a change.Direct workJeff and I want to support work that directly makes the world a better place. (Some arguments against falling into a “meta trap” here.) As usual for us, this year we’ve given just over half our donations to direct work. We made these donations to the Against Malaria Foundation, one of GiveWell’s top picks, except for small amounts th…

via Giving Gladly December 30, 2016

Practical steps for self-care

Last week the Boston Effective Altruism group had a discussion on self-care for altruists. I've written about the topic before, but I wanted to share some of the more practical advice people had. Think beyond day-to-day choicesSelf-care isn’t just short-term decisions like whether to make time for yoga tonight. It’s larger life decisions too, like what job to take, where to live, how to budget money, and how to make time for partners, friends, and family.For me, having children was self-car…

via Giving Gladly June 15, 2016

via openring