Missile lock-on!

Friday, August 31st, 2018

I was listening to the audio version of David Suarez’s techno-thriller Kill Decision, when the pilot of the good guys’ C-130 announced “missile lock-on!” How exactly does missile lock-on work, and how does the target know it’s locked on?

Aircraft radars typically have two modes: search and track. In search mode, the radar sweeps a radio beam across the sky in a zig-zag pattern. When the radio beam is reflected by a target aircraft, an indication is shown on the radar display. In search mode, no single aircraft is being tracked, but the pilot can usually tell generally what a particular radar return is doing because with each successive sweep, the radar return moves slightly.


In track mode, the radar focuses its energy on a particular target. Because the radar is actually tracking a target, and not just displaying bricks when it gets a reflection back, it can tell the pilot a lot more about the target.


An important thing to note is that a radar lock is not always required to launch weapons at a target. For guns kills, if the aircraft has a radar lock on a target, it can accurately gauge range to the target, and provide the pilot with the appropriate corrections for lead and gravity drop, to get an accurate guns kill. Without the radar, the pilot simply has to rely on his or her own judgement.


And what about missiles? Again, a radar lock is not required. For heat-seeking missiles, a radar lock is only used to train the seeker head onto the target. Without a radar lock, the seeker head scans the sky looking for “bright” (hot) objects, and when it finds one, it plays a distinctive whining tone to the pilot. The pilot does not need radar in this case, he just needs to maneuver his aircraft until he has “good tone,” and then fire the missile. The radar only makes this process faster.

Now, radar-guided missiles come in two varieties: passive and active. Passive radar missiles do require a radar lock, because these missiles use the aircraft’s reflected radar energy to track the target.

Active radar missiles however have their own onboard radar, which locks and tracks a target. But this radar is on a one-way trip, so it’s considerably less expensive (and less powerful) than the aircraft’s radar. So, these missiles normally get some guidance help from the launching aircraft until they fly close enough to the target where they can turn on their own radar and “go active.” (This allows the launching aircraft to turn away and defend itself.) It is possible to fire an active radar missile with no radar lock (so-called “maddog”); in this case, the missile will fly until it’s nearly out of fuel, and then it will turn on its radar and pursue the first target it sees. This is not a recommended strategy if there are friendly aircraft in close proximity to the enemy.


Radar is just radio waves, and just as your FM radio converts radio waves into sound, so can an aircraft analyze incoming radio signals to figure out who’s doing what. This is called an RWR, or radar warning receiver, and has both a video and audio component.


Each time a new radar signal is detected, it is converted into an audio wave and played for the pilot. Because different radars “sound” different, pilots learn to recognize different airborne or surface threats by their distinctive tones. The sound is also an important cue to tell the pilot what the radar is doing: If the sound plays once, or intermittently, it means the radar is only painting our aircraft (in search mode). If a sound plays continuously, the radar has locked onto our aircraft and is in track mode, and thus the pilot’s immediate attention is demanded. In some cases, the RWR can tell if the radar is in launch mode (sending radar data to a passive radar-guided missile), or if the radar is that of an active radar-guided missile. In either of these cases, a distinctive missile launch tone is played and the pilot is advised to immediately act to counter the threat. Note that the RWR has no way of knowing if a heat-seeking missile is on its way to our aircraft.

Who cares how much carbon dioxide is on Mars?

Thursday, August 30th, 2018

The whole argument over how much carbon dioxide is on Mars now is totally irrelevant, since we need to import far, far more nitrogen to terraform the planet:

The surface pressure on Mars now averages about 0.6 percent of our own sea level pressure, or about 0.087 psi (600 pascals), and is thus a “physiological vacuum”. This means the pressure is less than a tenth of the “Armstrong Limit” of about 0.9 psi (6,200 pascals) where blood boils and far below what is needed to survive even with pure oxygen. You would need to wear a pressure suit to survive on the surface, just like on the Moon. Fortunately, though chilly, the temperatures on Mars are much milder than those on the Moon.

In addition, the surface of Mars is exposed to about 250 millisieverts (mSv) per Earth year of solar and galactic (cosmic) radiation, composed partly of dangerous high-speed atomic nuclei that can leave a trail of dead brain cells behind. Due to these particles, cosmic radiation is more dangerous than “regular” radiation. Crews and early civilian settlers would need to live underground in heavily shielded, pressurized habitat buildings to prevent the cosmic ray nuclei from reaching them. For reference, you would experience some radiation sickness if you got a dose of 1000 mSv all at once. In interplanetary space, you would get about 657 mSv per year without shielding, but on Mars, the planet itself blocks half of the radiation and the thin atmosphere absorbs another 20 percent of what remains. At this lower but constant rate, you would not get sick but there would be cumulative cell damage and a slow increase in cancer risk. On Earth, at sea level, we have in effect a layer of air equivalent in mass to 10.3 meters of water over our heads, which absorbs virtually all of the dangerous high-energy particles. On Mars, that layer is equivalent to about 20 centimeters of water, barely enough to shield anyone from a dangerous solar “proton storm” radiation outburst.

So there are three main reasons we need significant air pressure on Mars: to remove the need for pressure suits when working outside (and so that we would no longer need to live in pressurized habitats), to allow water to exist as a liquid on the surface, and to block the ubiquitous cosmic radiation so that buildings can be right on the surface and so that people can work on the surface without being irradiated. We can look at this issue from two points of view: radiation blocking mass and air pressure. So how much air mass and pressure do we really need?

From the radiation perspective, this is primarily a matter of sheer mass. On Earth at sea level, we have enough air over our heads so that only a tiny fraction of the natural background radiation most people get per year, totaling 3 to 6 mSv, is from space. To duplicate that very good level of protection on Mars requires a comparable amount of air mass (10.3 metric tons) over every square meter of Mars surface, ignoring the great altitude differences. Multiply this by the number of square meters of Mars surface and you get the required air mass: 1.493 trillion metric tons. This amount would create about 6.14 psi of air pressure or about 0.42 of Earth sea level pressure. More importantly, essentially all of the dangerous cosmic radiation from space would be blocked. This compares to the paltry 25 trillion metric tons of air currently in place at Mars, almost all of it CO2.

Some may note that for the same air column mass (the mass of air over a given surface area), we are not getting as much air pressure as we do on Earth. With Mars lower gravity, about 38% of Earths, it takes more air mass per square meter than it does on Earth to produce the same amount of pressure. So with the radiation threat now (theoretically) dealt with, how much air pressure do we need and what kind?

Right now, the air you are breathing is about 78 percent nitrogen and only about 21 percent oxygen. Carbon dioxide is a trace gas, at only 0.04 percent. You actually breathe 25 times more argon than carbon dioxide. If you are old enough, or are a space history buff, you may remember the Apollo 1 fire. The first Apollo spacecraft being prepared to be launched with a crew had about 16 psi of pure oxygen inside it during a pre-launch test, and all of the metal and plastic surfaces were saturated with oxygen. The capsule interior was like a fire bomb waiting for one tiny spark. The three astronauts were quickly asphyxiated by smoke within a minute of that spark and most of the interior of the capsule was incinerated. This horrific accident illustrates how dangerous high levels of oxygen are.

So future colonists would have little use for an atmosphere of almost all carbon dioxide, and they would not want an atmosphere mostly of oxygen due to the huge fire risk it would create. It turns out that the oxygen in any future nitrogen-oxygen atmosphere should be less than 50 percent of the total air pressure, but with the 42 percent pressure described above, we would still need a future 50-50 oxygen and nitrogen mix. (The amount of nitrogen delivered should be related to the future oxygen component.) So if we increase the air column mass to about 12.3 metric tons over each meter of surface, we get almost exactly half sea level pressure, or about 7.35 psi. To create this half-atmosphere of pressure (almost all of nitrogen) we need to add 1,784 trillion tons of nitrogen. However, this is equivalent to an altitude on Earth of about 5,200 meters, the altitude of the highest community on Earth in the Andes.

We assume, once we have a half-atmosphere of pressure, early settlers would be using oxygen helmets when working outside, and living inside slightly pressurized habitats, which could then be on the surface, with a nitrogen-oxygen mix. In addition, those in charge of the terraforming process would want to find ways to slowly add oxygen to the atmosphere, such as using the oxygen in some of the carbon dioxide and the existing water on Mars. This may take a long time, but adding oxygen will also add to the atmospheric pressure. Eventually, perhaps after centuries, there would be enough oxygen to breath and green plants could grow outside, but not so much as to be dangerous. A reasonable mix at about 10 psi would obviously be 70 percent nitrogen and 30 oxygen oxygen, providing the needed 3 psi of oxygen. This would be similar to being at about 3,000 meters on Earth, which the majority of people can obviously tolerate. For example, the town of Leadville, Colorado, is at an altitude of 3,100 meters. This is why we want the nitrogen in place first as it is a non-reactive gas.

Wait, I have a question:

Now, of course, many people will wonder where do we get all of these trillions of tons of nitrogen to import onto Mars. The planet has very little of it: just a few percent of what is needed, as most of it was lost during the last 3.5 billion years. However, It turns out that the outer solar system has huge amounts of nitrogen, both as a gas, such as on Titan, and as a semi-solid slush or ice on Pluto, Triton, and very probably the other large Kuiper Belt dwarf planets. Small asteroids would not have significant amounts of nitrogen as their gravity would have been too low to hold an atmosphere. We should be able to mine some of this nitrogen and move it to Mars where it can help support life. The current atmospheric loss rate from Mars would be very low.

Right now, it is true we have no means of moving the nitrogen, but chances are, with the new private investments in fusion power, that we will have it before we are ready to start terraforming. Fusion rocket powered tugs would only need to thrust for a few days to a couple weeks to send huge loads of nitrogen—as much as 100 million tons in each load—into the inner solar system at low speeds and carefully intersect the atmosphere of Mars. Ten such loads would deliver a billion tons of nitrogen, as much mass as a cubic kilometer of water, and 10,000 loads would deliver a full trillion tons.

The image at the top of this article shows a load of 100,000 chunks of nitrogen (shown as cubes but they could be in huge plastic bags.) Each chunk is about 10 meters across and weighs about 1,000 tons. By aiming these large loads of nitrogen ice so that they come in exactly horizontally at the high atmosphere of Mars over the desired areas, instead of impacting on Mars surface, there are no craters formed and all of the nitrogen is turned into gas and added to the atmosphere over an entry path of hundreds of kilometers. Very large amounts of heat, but no dangerous radiation, are created by these entries, which would occur many times a day and go on for over 100 years.

The entries could be targeted over the ice caps or glaciers and would easily melt them totally, as each entry produces as much radiant heat as a hydrogen bomb but with no dangerous radiation. Thus, the ice cap melting can be done by these repeated entry events, instead of a few, very dangerous cratering events. The fusion tugs back away from their loads before entry and head back to the outer solar system at high speed since they now have no load. Climatologists may have to hurry to get valuable ice cores of all the ice cap areas before they are melted to form a new, but initially shallow, Boreal Ocean and other bodies of water.

Easy-peasy then!

Everything about Stratolaunch is supersized

Wednesday, August 29th, 2018

Everything about Stratolaunch is supersized:

It has six screaming Pratt & Whitney turbofan jet engines, salvaged from three 747s. Its maximum takeoff weight is 1.3 million pounds. It’s got more than 80 miles of wiring. Most astounding is its 385-foot wingspan, the spec that puts Stratolaunch in the history books.


One problem with ground-based rockets is that they can take off from only a small number of facilities, like the Kennedy Space Center or Vandenberg Air Force Base, where competition for launch time creates long delays. A plane-based launch would create new possibilities.

But a plane that big had other challenges. Rutan’s analysis concluded that to deliver the weight of the rocket Elias was talking about—up to 640,000 pounds—you’d need a wingspan of almost 400 feet. That wing had to be strong too. In addition to two fuselages and tons of fuel, it would be carrying a set of jet engines and that massive vehicle. Rutan planned to build the plane from nonmetal composites, rather than aluminum, to keep the weight down, but making the composite strong enough presented another problem. Rutan solved this dilemma in part with a process called pultrusion, in which a machine pulls a material at a constant rate and then bakes it until it hardens, a way to mold huge segments of the plane with a consistent strength. This technique let the engineers manufacture the very long spars that fortify the giant wing.

Rutan began working on a design, even as he realized that the odds were against it ever being built. Using traditional construction methods and materials, the price tag might stretch past a billion, perhaps even reaching the cost of a nuclear aircraft carrier. He figured he could build it more cheaply, especially if he took his scavenger mentality to the limit. “I reasoned that if I could lift out engines, pylons, landing gear, actuators, electricals, and cockpit stuff from 747s, it was doable for us,” he says.


The team worked to speed up construction by using off-the-shelf parts whenever possible, the most conspicuous example being the repurposing of three 747s. But the surface of the plane had to be created from scratch. “This vehicle has some of the largest composite components ever built in the world, made by hand by fabricators, all made by our guys,” says Jacob Leichtweisz­-Fortier, who works on the plane. The most massive pieces were 285-foot spars that give the wing its resiliency, each one weighing 18,000 pounds. The team first constructed the wing out of the gargantuan spars and built the rest of the plane around it.

The plane’s extreme size led to some unexpected complications: The scaffolding needed to assemble the wing had to be about 40 feet high. “It starts to look like a building,” Stinemetze says. “In fact, the way California treats it, it is a building. It has to meet codes for sprinklers and electrical power.” When the plane was ready to emerge from its scaffolding and get towed out of the hangar, just lowering it 2 feet to the ground took eight hours, Floyd says.


Sharing their road map publicly for the first time, Thornburg and Floyd laid out their plans for Stratolaunch: Its first custom rocket ship will be considerably bigger than the Pegasus, able to transport multiple satellites or other payloads. This medium-size rocket is nicknamed Kraken, after the legendary Icelandic sea monster. Floyd says customers will be able to use it to get satellites into low Earth orbit for less than $30 million, a competitive price and about half of what SpaceX charges for a launch of its Falcon 9 rocket. Floyd estimates that Kraken will be operational in 2022.

Release the Kraken!

Collaborate on complex problems, but only intermittently

Tuesday, August 28th, 2018

A new study suggests that teams should collaborate on complex problems, but only intermittently:

Bernstein, Assistant Professor Jesse Shore of the Questrom School of Business at Boston University, and Professor David Lazer of Northeastern University put together and studied a number of three-person groups performing a complex problem-solving task. The members of one set of groups never interacted with each other, solving the problem in complete isolation; members of another set constantly interacted, as we do when equipped with always-on technologies; and members of the third set of groups interacted only intermittently.

From prior research, the researchers anticipated that the groups whose members never interacted would be the most creative, coming up with the largest number of unique solutions — including some of the best and some of the worst — and a high level of variation that sprang from their working alone. In short, they expected the isolated individuals to produce a few fantastic solutions but, as a group, a low average quality of solution due to the variation. That proved to be the case.

The researchers also anticipated that the groups whose members constantly interacted would produce a higher average quality of solution, but fail to find the very best solutions as often. In other words, they expected the constantly interacting groups’ solutions to be less variable but at the cost of being more mediocre. That proved to be the case as well.

But here’s where the researchers found something completely new: Groups whose members interacted only intermittently preserved the best of both worlds, rather than succumbing to the worst. These groups had an average quality of solution that was nearly identical to those groups that interacted constantly, yet they preserved enough variation to find some of the best solutions, too.

Perhaps the most interesting result was that when their interactions were intermittent, the higher performers were able to get even better by learning from the low performers. When high and low performers interacted constantly, the low performers tended to simply copy high performers’ solutions and were in turn generally ignored by the high performers. But when their interactions were intermittent, the low performers’ ideas helped the high performers achieve even better solutions.

Bernstein and his co-authors see a number of workplace implications for these findings, including the advantages of alternating independent efforts with group work over a period of time. In some ways, that’s how work traditionally has been done in organizations — with individuals working alone, then coming together in a meeting, then returning to work alone. But advancing technology has changed those cycles.

A Golden Era of live-action sitcoms for six-year-olds

Monday, August 27th, 2018

If you are a mid-Baby Boomer born in the late 1950s, Steve Sailer suggests, you probably have a memory of the mid-1960s as a Golden Era of live-action sitcoms for six-year-olds, such as Gilligan’s Island, Get Smart, Adams Family, Munsters, Green Acres, I Dream of Jeannie, and Bewitched:

It’s not clear if it really was a halcyon era or if all six-year-olds look back fondly on the TV shows when they were six. In the defense of the former view, I don’t recall that many animated shows from the same era. (I was a big fan of Johnny Quest, though.)

I think it’s plausible that a lot of money and talent poured into sitcoms in 1964-65, creating a brief period of shows that appealed both to grown-ups and kids. Bewitched, for instance, started out as a relatively straightforward study of the sociological stresses of a mixed marriage. (Marrying a shiksa was a huge theme looming just below the surface in 1960s TV, although in Bewitched the allegory is kept ambiguous. Elizabeth Montgomery, for example, was the daughter of Hollywood Republican stalwart Robert Montgomery.) But the network kept demanding more goofy magic For the Kids.

The latter two shows involved ladies in mixed (magical/human) relationships who use magic to get their housekeeping chores done (a concept that greatly appealed to my future wife at the time), while the man of the house disapproves of the woman taking unfair advantage of her powers to make his life better, but the woman knows best what he really needs.

Also, both magical ladies have relatives who disapprove of the man of the house, such as Darren’s mother-in-law Endora (Agnes Moorhead), brunette evil twin Serena (Elizabeth Montgomery in a dual role), and Uncle Arthur (Paul Lynde — I was surprised to see the memorable Lynde only appeared in 10 of the 254 episodes).

If you’re a bit younger than Sailer, you probably remember all the shows from that Golden Era of live-action sitcoms for six-year-olds as childhood favorites, only in reruns.

Anyway, Sailer was spurred to write about this after reading about a potential Bewitched remake from Black-ish creator Kenya Barris:

In Bewitched, written by Barris and Taylor, Samantha, a hardworking black single mom who happens to be a witch, marries Darren, a white mortal who happens to be a bit of a slacker. They struggle to navigate their differences as she discovers that even when a black girl is literally magic, she’s still not as powerful as a decently tall white man with a full head of hair in America.


Call it moxie

Monday, August 27th, 2018

Gregory Clark finds that social status is strongly heritable, and Gregory Cochran runs with this:

Combined with a very high degree of assortative mating for the genetic factors behind this heritability, social mobility is surprisingly low. This happens without anyone particularly trying to make it this way — although it can happen less if people do try to stop it. An interesting example out of Plomin’s group: genetics explains “twice as much variance in educational attainment and occupational status in the post-Soviet era compared with the Soviet era.”

Plomin (or maybe more exactly his student Kaili Rimfeld) says that “The extent of genetic influence on these social outcomes can be viewed as an index of success in achieving meritocratic values of equality of opportunity by rewarding talent and hard work, which are to a large extent influenced by genetic factors, rather than rewarding environmentally driven privilege. ”

I don’t think that statement is entirely wrong. Estonia today is better run than it was in 1953, or 1990. But I am just as sure that it isn’t entirely right. We’re talking about genetic factors that tend to increase social status: intelligence helps, sure, but the people at the top, the people running the show are rarely the smartest — or the most decent, or the most effective. If we define ‘merit’ as a tendency to effective action that favors the best interest of society as a whole — surely what high-status people have more of is only loosely associated with ‘merit’. They have more of what works for themselves. Call it moxie.

So the ideal social policy would attempt — and succeed — at picking people for high-status job that were good at getting the job done — not just good at getting the job. Talent and hard work are influenced by genetic factors, but then so is being a back-stabbing, credit-stealing asshole.

I don’t think it would be easy: nature’s agin it. But it’s possible. I think. To a degree.

What should the Classical Greeks have done with Alcibiades, who surely had enough genetic moxie for a platoon? Answer: shoot the bastard. Him better off dead.

Its aerial roots drip with a thick, clear, glistening mucus that’s loaded with bacteria

Sunday, August 26th, 2018

Corn, or maize, originated in southern Mexico, when it was domesticated from a wild cereal called teosinte, and the region is still home to the greatest diversity of the crop, including a unique variety that uses air as fertilizer:

For thousands of years, people from Sierra Mixe, a mountainous region in southern Mexico, have been cultivating an unusual variety of giant corn. They grow the crop on soils that are poor in nitrogen — an essential nutrient — and they barely use any additional fertilizer. And yet, their corn towers over conventional varieties, reaching heights of more than 16 feet.

A team of researchers led by Alan Bennett from UC Davis has shown that the secret of the corn’s success lies in its aerial roots — necklaces of finger-sized, rhubarb-red tubes that encircle the stem. These roots drip with a thick, clear, glistening mucus that’s loaded with bacteria. Thanks to these microbes, the corn can fertilize itself by pulling nitrogen directly from the surrounding air.

Aerial roots of corn from Sierra Mixe

The Sierra Mixe corn takes eight months to mature — too long to make it commercially useful. But if its remarkable ability could be bred into conventional corn, which matures in just three months, it would be an agricultural game changer.

All plants depend on nitrogen to grow, and while there’s plenty of the element in the air around us, it’s too inert to be of use. But bacteria can convert this atmospheric nitrogen into more usable forms such as ammonia — a process known as fixation. Legumes, like beans and peas, house these nitrogen-fixing bacteria in their roots. But cereals, like corn and rice, largely don’t. That’s why American farmers need to apply more than 6.6 million tons of nitrogen to their corn crops every year, in the form of chemical sprays and manure.

Incentives boost effort on IQ tests

Saturday, August 25th, 2018

Will intelligence test-taking performance increase if people are paid $75 to do well on the test? James Thompson takes a look:

This is an interesting question, because critics of intelligence testing have argued that some groups get low scores because they are not interested in the test, and can’t see the point of solving the problems. Perhaps so, although if you don’t get motivated by trying to solve problems that might be diagnostic in itself.

Gilles Gignac decided to have a look at this argument, seeing whether the offer of winning $75 Australian dollars boosted intelligence test scores in university students. For once, I am not too bothered by the subjects being university students, because they tend to have modest funds and healthy appetites.


The financial incentive was observed to impact test-taking effort statistically significantly. By contrast, no statistically significant effects were observed for the intelligence test performance scores.


One reason why test-taking motivation is correlated with intelligence test scores may be that bright people like solving problems. If they have to take a test, they look forward to it, knowing they usually do well, and are interested in finding out precisely how well they do. Less able students don’t like tests, and particularly get discouraged when they relate to difficult subjects.

Doomsday prepping for less crazy folk

Friday, August 24th, 2018

Michal Zalewski discusses doomsday prepping for less crazy folk:

The prepper culture begs to be taken with a grain of salt. In a sense, it has all the makings of a doomsday cult: a tribe of unkempt misfits who hoard gold bullion, study herbalism, and preach about the imminent collapse of our society.

Today, we see such worries as absurd. It’s not that life-altering disasters are rare: every year, we hear about millions of people displaced by wildfires, earthquakes, hurricanes, or floods. Heck, not a decade goes by without at least one first-class democracy lapsing into armed conflict or fiscal disarray. But having grown up in a period of unprecedented prosperity and calm, we take our way of life for granted – and find it difficult to believe that an episode of bad weather or a currency crisis could destroy almost everything we worked for to date.

I suspect that we dismiss such hazards not only because they seem surreal, but also because worrying about them makes us feel helpless and lost. What’s more, we follow the same instincts to tune out far more pedestrian and avoidable risks; for example, most of us don’t plan ahead for losing a job, for dealing with a week-long water outage, or for surviving the night if our home goes up in smoke.

For many, the singular strategy for dealing with such dangers is to pray for the government to bail us out. But no matter if our elected officials prefer to school us with passages from Milton Friedman or from Thomas Piketty, the hard truth is that no state can provide a robust safety net for all of life’s likely contingencies; in most places, government-run social programs are severely deficient in funding, in efficiency, and in scope. Large-scale disasters pit us against even worse odds; from New Orleans in 2005 to Fukushima in 2011, there are countless stories of people left behind due to political dysfunction, poorly allocated resources, or lost paperwork.

And so, the purpose of this guide is to combat the mindset of learned helplessness by promoting simple, level-headed, personal preparedness techniques that are easy to implement, don’t cost much, and will probably help you cope with whatever life throws your way.

Moses the Microbiologist

Thursday, August 23rd, 2018

John Durant’s Paleo Manifesto is neither paleo, nor a manifesto — and that’s not a bad thing.

I recently revisited Chapter 4, titled Moses the Microbiologist.

I highlighted these passages:

  • However the books were actually written by multiple authors, include stories borrowed from neighboring cultures, sometimes diverge from the best history of the era, and weren’t compiled until long after Moses allegedly lived. Seen in that light, the story of Moses is more than the story of one man; it’s the collective memory of half the world’s people.

    Location: 740

  • Jewish scholars count 613 commandments (248 do’s and 365 don’ts), with thousands of long-standing interpretations and implications for daily life.

    Location: 749

  • How curious that one of those commandments ordered Jewish priests to wash their hands—one of the simplest and most effective forms of hygiene ever discovered—right at the moment in history when infectious disease was exploding. And this commandment came just after the part of the story where the Jewish people distinguish themselves as being impervious to plague.

    Location: 750

  • The flight from Egypt is also the moment in the story when the Jewish people transition from being pastoral herders to urban dwellers. If there is one people who not only made the transition to living in cities but also developed a reputation for thriving in cities, it is the Jewish people. Jewish culture has survived for some 3,000 years—arguably the oldest non-isolated culture with significant permanence—which suggests that it contains features that have allowed it to persist through the Agricultural Age and helped Jews adapt to life in the big city.

    Location: 753

  • Whether or not early agriculturalists realized it, many ancient cultural practices were adaptations against pathogens. For example, spices have antimicrobial properties, which made them a healthy addition to food in an era before refrigeration. It’s not a coincidence that equatorial ethnic cuisines are particularly spicy (food spoils faster in hot climates) and recipes for meat dishes tend to call for more spices than do vegetable dishes (meat spoils faster than plants). Water in early cities was often filthy, which helps explain the emergence of sterile alternatives such as wine (microbes can’t survive in alcohol) and hot tea (boiling kills microbes). Early people didn’t know that invisible bacteria were causing their cavities, but many still ended up using “toothbrushes”—wooden chewing sticks containing a natural antiseptic or treated with one.

    Location: 778

  • In reading the Torah, one thing becomes immediately clear: life was rife with disease. Not only does the Torah describe pestilence and plague in a general sense, it also mentions dozens of distinct diseases and illnesses. Yet the Jewish people seem miraculously exempt from pestilence—when they obey God’s laws.

    Location: 808

  • There’s much in the Law of Moses that remains mysterious or defies a simple explanation, but it is remarkable how much makes sense from a single point of view: infectious disease.

    Location: 814

  • Some of the rules unambiguously address infectious disease, with priests explicitly playing the role of healer. For example, the laws concerning “leprosy” read like a medical text (Leviticus 13–14). Though the modern condition known as leprosy isn’t itself described, the laws help healer-priests discern between multiple skin diseases and determine the appropriate treatment. The…

    Location: 815

  • immediate quarantine, washing, and in some cases hair removal. The laws also specify how to deal with “leprous” garments or dwellings. Garments had to be quarantined and washed; if that failed to halt the spread of infection, they had to be burned. Dwellings had to be emptied, contaminated stones had to be replaced, and the walls had to be…

    Location: 819

  • Far beyond the laws on leprosy, it’s fair to say the Mosaic Law is obsessed with cleanliness, stipulating a lengthy code of personal hygiene and public health—accounting for some 15–20% of the 613 commandments. Though many commandments applied only to priests, the practices often came to permeate Jewish culture, fulfilling the injunction: “ ‘And you shall be to Me a kingdom of priests and a holy nation’ ” (Exodus 19:6). Jewish scholars have written about the importance of ritual hygiene in Judaism for a very long time (it’s one of the oldest themes in…

    Location: 822

  • The Jewish hygiene code appears to be based on four…

    Location: 828

  • First, certain people, animals, or things are inherently “unclean.” Inorganic matter alone, such as dirt, doesn’t make someone “unclean” in the literal sense of “dirty.” Uncleanliness comes from organic matter, such as corpses, bodily fluids, insects, and certain animals. In many cases what the Jews call…

    Location: 828

  • Second, this “unclean” status is transferable through physical contact. In the same way that germs are transmissible, “unclean” things are…

    Location: 832

  • Third, an “unclean” person or object could become “clean” again through various purification rituals. It was as if these cleansing rituals were able to “…

    Location: 834

  • Fourth, individual “uncleanliness” affects the entire community. Akin to mandatory public health measures, the Mosaic Law applies to all Jews—and the text makes clear that Jews’ collective adherence to the Mosaic Law…

    Location: 836

  • However, ineffective rules may have been the price of a generalized obsession with potential routes of infection, and such a mindset would lead to practices that are genuinely hygienic.

    Location: 844

  • Honoring the dead benefited the living: quick burials make hygienic sense given how rapidly corpses decompose in a hot climate like that of the Middle East.

    Location: 855

  • Showing a similar wariness of corpses, Jews were not allowed to eat any animal that either died of its own accord or was killed by wild beasts (Leviticus 7:24, 11:39–40). Animals weakened by disease are more likely to drop dead or be picked off by predators, and, as with humans, a corpse lying out for long enough becomes a literal breeding ground for pathogens.

    Location: 858

  • With so many people dropping dead from disease, cannibalism was a recipe for infection—thus an ancient indigenous method of honoring the dead turned into an unthinkable taboo, used in curses as a sign of the ultimate defilement (Leviticus 26:29; Deuteronomy 28:52–57).

    Location: 862

  • The result was an ancient form of food inspection: the carcass and internal organs had to be examined for defects, signs of disease, or anything that might have caused the animal to die of its own accord in the near future. Later in history, Jews even inflated the lungs and submerged them in water to look for any leaks—a telltale sign of tuberculosis.

    Location: 867

  • Avoiding vermin and insects like the plague, as it were, would have been a simple and effective rule to avoid infectious disease.

    Location: 878

  • The “unclean” lizards and amphibians (Leviticus 11:29–30) are low disease risks, but they do perform a useful function: They eat scads of insects, which carry disease.

    Location: 888

  • The prohibitions against eating birds of prey appear to follow a similar ecological logic (Leviticus 11:13–19). Birds of prey eat vermin and other pests. Carrion fowl, such as the forbidden vultures, conveniently dispose of corpses (Leviticus 11:13–19), as do four-pawed carnivorous mammals (Leviticus 11:27).

    Location: 890

  • By excluding cats from the dinner menu, even the American diet reveals the influence of protecting a species that eats vermin.

    Location: 896

  • Zoroastrianism explicitly stipulated that all human corpses must be taken to a mountaintop, chained to the ground, and left to be devoured by corpse-eating wild dogs and birds (Avesta, Vendidad 6:44–51).

    Location: 899

  • Any direct contact with an unclean person (or thing) made someone (or something) unclean. For example, if a rodent carcass touched household objects or fell into food or water, it all became unclean (Leviticus 11:32–38). The idea that germs were transferable by even the slightest physical touch may seem obvious today, but it was an astonishing inference thousands of years before the formal discovery of the germ theory of disease in the late nineteenth century.

    Location: 923

  • As a result of water’s dual nature (easily transmitting uncleanliness, yet itself a source of purification), Jews became fixated on ensuring the purity of their water supply.

    Location: 932

  • One of those purification rituals requires an unclean person to take both hands and rinse them in clean water (Exodus 30:17–21; Leviticus 15:11; Deuteronomy 21:6).

    Location: 940

  • Another form of “ritual” purification required Jews to immerse themselves in a pool of water—also known as taking a bath.

    Location: 947

  • Observing the Sabbath was very important: the penalty for not observing a day of rest—taking a vacation day—was death (Exodus 31:12–17). In preparation, Jews had to undergo multiple purification rituals: take a bath, wash their hands, launder their clothes, and clean their home.

    Location: 954

  • The Jewish people also knew about at least one form of sterilization: fire.

    Location: 957

  • Here’s how to make that “water of purification”: slaughter a cow, burn it whole, and throw some “cedar wood and hyssop and scarlet” into the fire. Then take the ashes and add water (Numbers 19). Water, ash, and animal fat are ingredients for soap.

    Location: 961

  • Even though Jews stopped sacrificial slaughter thousands of years ago, Jewish rabbis offered a different interpretation of “water of purification”: scalding hot water (Talmud, Avodah Zarah 75b). As a result, Jews sterilized their dishes and eating utensils by submerging them in water that had been brought to a boil.

    Location: 965

  • Earthenware pots, which are porous and difficult to sterilize, had to be broken and could never be used again if they became unclean (Leviticus 6:28, 11:33). In contrast, bronze pots could be scoured and washed (Leviticus 6:28). Items made from wool, linen, leather, and wood could usually be washed (Leviticus 11:32, 13:53–59, 15:12; Numbers 31:20), though sometimes they had to be destroyed with fire (Leviticus 13:47–52).

    Location: 968

  • (In fact, this passage in Numbers became the basis for many rules governing any type of contact with Gentiles and their possessions, which were assumed to be unclean. This wariness of contact with filthy foreigners, plus an obsession with hand washing, would have given Jews an advantage in commerce, both as middlemen—as hubs in trade networks—and long-distance merchants visiting lands with novel pathogens—key edges in trade networks. Another people similarly distinguished are the Parsis of India; curiously, they are some of the last remaining followers of Zoroastrianism.)

    Location: 977

  • Not only did the physical plunder have to be cleaned of infection, so did the captive women (all the men were killed). Female captives were forced to shave their heads and trim their fingernails (Deuteronomy 21:10–12),

    Location: 981

  • Only virgin women could be captured; all other women had to be killed (Numbers 31:15–18). This was a direct result of past experience—see “the Peor incident” (Numbers 25)—when the Jewish soldiers kept all the conquered women alive, had sex with them, and brought a plague upon themselves.

    Location: 986

  • Early agricultural sex cults—of which there were more than a few—tended to die out. Religions that placed restrictions on our sexual impulses did not.

    Location: 995

  • The connection between cervical cancer and sexual activity was discovered by observing that celibate nuns were unafflicted by cervical cancer, whereas the affliction was relatively common among prostitutes.

    Location: 1006

  • Follow God’s hygiene rules and emerge unscathed from the great plagues that destroy rival peoples: a sign of God’s favor. Disobey God’s hygiene rules and be struck down by pestilence: a sign of God’s displeasure.

    Location: 1034

  • In Europe, from the Black Death onward, Fishberg uncovered reports of Jewish people dying at lower rates than Christians during major epidemics: a typhus epidemic in 1505; fevers in Rome in 1691; dysentery in Nimègue in 1736; and typhus in Langeons in 1824. By the nineteenth century, public health statistics revealed not only that the effect was real, but that it was enormous: a ten-year advantage in life expectancy in many European cities. This disparity was even more remarkable considering that Jews were often forced to live in crowded and damp urban ghettos—places conducive to the spread of disease.

    Location: 1076

Relying on the priests’ potentially corrupt interpretation

Wednesday, August 22nd, 2018

Sociologist Francesca Tripodi takes an ethnographic approach to studying how partisan groups interact with media:

There is a narrative out there, floating around the executive offices at Google and Facebook, lurking in the halls of prominent publications like The New York Times or The Washington Post, and emerging from the mouths of most cable news pundits that “fake news” has ruined democracy. Tied up in this narrative is an accusation that supporters of President Trump were “tricked” into voting for him because Russian bots fed them a steady stream of misinformation. If only, the story goes, there was some way to reach Trump supporters — who, according to a study by the Oxford University Computational Propaganda Project, more frequently like and share “fake news.” Why don’t they do their research? some bemoan. Don’t they check the facts? The assumption: If only they could learn to think critically, accessing, analyzing, and evaluating a variety of sources, then they would be informed voters.

The thing is — they do, and they are. During 2017, I began regularly attending Republican events associated with two upper-middle class communities in the Southeastern United States: a women’s group and a college group. [...] At one point during the meeting, the Pastor turned from the Bible to the new tax reform bill, where he encouraged the group to apply the same “deep reading.” The group poured over the text together, helping each other decide what it really meant rather than relying on mainstream media coverage of the bill. In that moment, I realized that this community of Evangelical Christians were engaged in media literacy, but used a set of reading practices secular thinkers might be unfamiliar with. I’ve seen hundreds of Conservative Evangelicals apply the same critique they use for the Bible, arguably a postmodern method of unpacking a text, to mainstream media — favoring their own research on topics rather than trusting media authorities.


Distrust in translation of text also explains why the debate-watching parties I attended favored television stations without pundits, like C-SPAN. They did not need CNN to tell them who had won; they relied on Trump’s words to signify that the values they described to me as “faith, family, the constitution, and national security” would be protected. The style of media literacy that I witnessed among Conservative groups helps explain the strategy of several prominent Conservative media organizations. These organizations stress that liberal ideology is formed by disputable claims and emotional appeals instead of fact-based evidence.


Herein lies the problem with media literacy approaches. Based on my data, upper-middle class Conservatives did not vote for Trump because they were “fooled” into doing so by watching, reading, or listening to “fake news.” Rather, they consumed a great deal of information and found inconsistencies, not within the words of Trump himself, but rather within the way mainstream media “twisted his words” to fit a narrative they did not agree with. Not unlike their Protestant ancestors, doing so gave them authority over the text rather than relying on the priests’ (i.e. “the elites’”) potentially corrupt interpretation.

Cresson H. Kearny’s survival skills

Tuesday, August 21st, 2018

Eugene P. Wigner, physicist, Nobel laureate, and, in May, 1979, the only surviving initiator of the Nuclear Age, wrote this about Cresson H. Kearny, the author of Nuclear War Survival Skills:

When the U.S. Atomic Energy Commission authorized me in 1964 to initiate the Civil Defense Project at Oak Ridge National Laboratory, one of the first researchers I recruited was Cresson H. Kearny. Most of his life has been preparation, unplanned and planned, for writing this guide to help people unfamiliar with the effects of nuclear weapons improve their chances of surviving a nuclear attack. During the past 15 years he has done an unequaled amount of practical field work on basic survival problems, without always conforming to the changing civil defense doctrine.

After I returned to my professional duties at Princeton in 1966, the civil defense effort at Oak Ridge National Laboratory was first headed by James C. Bresee. and is now headed by Conrad V. Chester. Both have wholeheartedly supported Kearny’s down-to-earth research. and Chester was not only a codeveloper of several of the survival items described in this book, but also participated in the planning of the experiments testing them.

Kearny’s concern with nuclear war dangers began while he was studying for his degree in civil engineering at Princeton — he graduated summa cum laude in 1937. His Princeton studies had already acquainted him with the magnitude of an explosion in which nuclear energy is liberated, then only a theoretical possibility. After winning a Rhodes Scholarship, Kearny earned two degrees in geology at Oxford. Still before the outbreak of World War II. he observed the effective preparations made in England to reduce the effects of aerial attacks. He had a deep aversion to dictatorships, whether from the right or left, and during the Munich crisis he acted as a courier for an underground group helping anti-Nazis escape from Czechoslovakia.

Following graduation from Oxford, Kearny did geological exploration work in the Andes of Peru and in the jungles of Venezuela. He has traveled also in Mexico, China. and the Philippines.

A year before Pearl Harbor, realizing that the United States would soon be at war and that our jungle troops should have at least as good personal equipment. food, and individual medical supplies as do exploration geologists. he quit his job with the Standard Oil Company of Venezuela. returned to the United States, and went on active duty as an infantry reserve lieutenant. Kearny was soon assigned to Panama as the Jungle Experiment Officer of the Panama Mobile Force. In that capacity he was able to improve or invent, and then thoroughly jungle-test, much of the specialized equipment and rations used by our jungle infantrymen in World War II. For this work he was promoted to major and awarded the Legion of Merit.

To take his chances in combat, in 1944 the author volunteered for duty with the Office of Strategic Services. As a demolition specialist helping to limit the Japanese invasion then driving into the wintry mountains of southern China, he saw mass starvation and death first hand. The experiences gained in this capacity also resulted in an increased understanding of both the physical and emotional problems of people whose country is under attack.

Worry about the increasing dangers of nuclear war and America’s lack of civil defense caused the author in 1961 to consult Herman Kahn, a leading nuclear strategist. Kahn, who was at that time forming a nonprofit war-research organization, the Hudson Institute, offered him work as a research analyst. Two years of civil defense research in this “think tank” made the author much more knowledgeable of survival problems.

In 1964 he joined the Oak Ridge civil defense project and since then Oak Ridge has been Kearny’s base of operations, except for two years during the height of the Vietnam war. For his Vietnam work on combat equipment, and also for his contributions to preparations for improving survivability in the event of a nuclear war, he received the Army’s Decoration for Distinguished Civilian Service in 1972.

This book draws extensively on Kearny’s understanding of the problems of civil defense acquired as a result of his own field testing of shelters and other survival needs, and also from an intensive study of the serious civil defense preparations undertaken by other countries, including Switzerland. Sweden, the USSR, and China. He initiated and edited the Oak Ridge National Laboratory translations of Soviet civil defense handbooks and of a Chinese manual, and gained additional knowledge from these new sources. Trips to England, Europe, and Israel also expanded his information on survival measures. which contributed to the Nuclear War Survival Skills. However, the book advocates principally those do-it-yourself instructions that field tests have proved to be practical.

Quickly breach without heat or sparks

Monday, August 20th, 2018

I feel like I need a PyroLance now:

The historical inspiration for the novel was not, actually, the American Revolution

Sunday, August 19th, 2018

Travis Corcoran’s The Powers of the Earth recently won the Prometheus Award (for best libertarian sci-fi novel of the year), and he penned this acceptance speech:

I’m sorry I couldn’t be here tonight, but I live on a farm and it’s harvest season in the Granite State. Live free or die!

I first heard of the Prometheus Award a quarter century ago and put “writing a novel worthy of winning it” on my bucket list. It was an amazing honor to be nominated alongside so many other worthy authors, and I can still barely wrap my head around having won.

Eric S Raymond said it best: “Hard SF is the vital heart of the field”. The core of hard science fiction is libertarianism: “ornery and insistent individualism, veneration of the competent man, instinctive distrust of coercive social engineering”.

I agree; science fiction is best when it tells stories about free people using intelligence, skills and hard work to overcome challenges.


The Powers of the Earth is a novel about many things.

It’s a war story about ancaps, uplifted dogs, and AI fighting against government using combat robots, large guns, and kinetic energy weapons.

It’s an engineering story about space travel, open source software, tunnel boring machines, and fintech.

It’s a cyberpunk story about prediction markets, CNC guns, and illegal ROMs.

It’s a story about competent men who build machines, competent women who pilot spaceships, and competent dogs who write code.

It’s a novel that pays homage to Heinlein’s The Moon is a Harsh Mistress, which in turn pays homage to the American Revolution.

…But the historical inspiration for the novel was not, actually, the American Revolution. It’s the founding of the Icelandic Free State almost a thousand years earlier. The difference is subtle, but important.

The American Revolution was an act of secession: one part of a government declaring itself independent and co-equal, and continuing to act as a government. The establishment of the Icelandic Free State is different in two important particulars. First, it did not consist of people challenging an existing government, but of people physically leaving a region governed by a tyrant. And second, the men and women who expatriated themselves from the reign of Harald Fairhair did not create a government — they wanted to flee authoritarianism, not establish their own branch of it!

(The Kindle edition is currently 99 cents.)

Highlights from James Gleick’s Genius: The Life and Science of Richard Feynman

Sunday, August 19th, 2018

I was recently reminded of Feynman’s anecdote about an early wartime engineering job he had, recounted in Surely You’re Joking, Mr. Feynman!, and that nudged me to move James Gleick’s biography, Genius: The Life and Science of Richard Feynman, to the front of my reading queue.

Since I had the Kindle version, I was able to export my “highlights” — although that required a third-party tool called Bookcision:

  • The adult Feynman asked: If all scientific knowledge were lost in a cataclysm, what single statement would preserve the most information for the next generations of creatures? Location: 705
  • “All things are made of atoms—little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another,” Location: 707
  • Heat had seemed to flow from one place to another as an invisible fluid—“phlogiston” or “caloric.” But a succession of natural philosophers hit on a less intuitive idea—that heat was motion. Location: 725
  • In Switzerland Daniel Bernoulli derived Boyle’s law by supposing that pressure was precisely the force of repeated impacts of spherical corpuscles, and in the same way, assuming that heat was an intensification of the motion hither and thither, he derived a link between temperature and density. Location: 728
  • Visitors less interested in science could pay to see an unemployed actress named Sally Rand dance with ostrich-feather fans. Location: 781
  • When there are a dozen Babe Ruths, there are none. Location: 809
  • They went to the Egyptian section, first studying glyphs in the encyclopedia so that they could stand and decode bits of the chiseled artifacts, a sight that made people stare. Location: 869
  • In just over a decade of full-scale commercial production, the radio had penetrated nearly half of American households. Location: 872
  • If a boy named Morrie Jacobs told him that the cosine of 20 degrees multiplied by the cosine of 40 degrees multiplied by the cosine of 80 degrees equaled exactly one-eighth, he would remember that curiosity for the rest of his life, and he would remember that he was standing in Morrie’s father’s leather shop when he learned it. Location: 892
  • For now, knowledge was scarce and therefore dear. Location: 896
  • Richard spent fifteen dollars on a special entrance examination for Columbia University, and after he was turned down he long resented the loss of the fifteen dollars. MIT accepted him. Location: 939
  • Mathematics is always where they begin, for no other school course shows off their gifts so clearly. Location: 958
  • The theories must make reasonably good predictions about experiments. That is all. Location: 999
  • It follows the path of least time. (Fermat, reasoning backward, surmised that light must travel more slowly in denser media. Later Newton and his followers thought they had proved the opposite: that light, like sound, travels faster through water than through air. Fermat, with his faith in a principle of simplicity, was right.) Location: 1057
  • “Our friend Dirac, too, has a religion, and its guiding principle is ‘There is no God and Dirac is His prophet.’” Location: 1067
  • Having chosen a fraternity, one instantly underwent a status reversal, from an object of desire to an object of contempt. Location: 1147
  • Fortunately they had calculators, a new kind that replaced the old hand cranks with electric motors. Location: 1432
  • In Germany a young would-be theorist could spend his days hiking around alpine lakes in small groups, playing chamber music and arguing philosophy with an earnest Magic Mountain volubility. Location: 1449
  • Feynman had developed an appetite for new problems—any problems. He would stop people he knew in the corridor of the physics building and ask what they were working on. Location: 1535
  • The committee had seen its share of one-sided applicants but had never before admitted a student with such low scores in history and English on the Graduate Record Examination. Feynman’s history score was in the bottom fifth, his literature score in the bottom sixth; and 93 percent of those who took the test had given better answers about fine arts. Location: 1565
  • We have no definite rule against Jews but have to keep their proportion in our department reasonably small because of the difficulty of placing them. Location: 1570
  • In the close, homogenous university communities, code words were attractive or nice. Location: 1592
  • “Surely you’re joking, Mr. Feynman!” Location: 1798
  • Feynman quietly nursed an attachment to a solution so radical and straightforward that it could only have appealed to someone ignorant of the literature. Location: 1851
  • Implicit in Feynman’s attitude was a sense that the laws of nature were not to be discovered so much as constructed. Location: 1860
  • They assured their readers that these were analogies, though analogies with the newly formidable weight of mathematical rectitude. Location: 1868
  • Another was John Tukey, who later became one of the world’s leading statisticians. Location: 1898
  • Seventeen years later, in 1956, the flexagons reached Scientific American in an article under the byline of Martin Gardner. “Flexagons” launched Gardner’s career as a minister to the nation’s recreational-mathematics underground, through twenty-five years of “Mathematical Games” columns and more than forty books. Location: 1917
  • They discovered that Feynman could read to himself silently and still keep track of time but that if he spoke he would lose his place. Tukey, on the other hand, could keep track of the time while reciting poetry aloud but not while reading. Location: 1934
  • But in the inverse case, when water is sucked in, there are no jets. The water is not organized. It enters the nozzle from all directions and therefore applies no force at all. Location: 1989
  • If there is a disease whose symptom is the belief in the ability of logic to control vagarious life, it afflicted Feynman, along with his chronic digestive troubles. Even Arline Greenbaum, sensible as she was, could spark flights of reason in him. Location: 2122
  • A movie showing a drop of ink diffusing in a glass of water looks wrong when run backward. Yet a movie showing the microscopic motion of any one ink molecule would look the same backward or forward. Location: 2181
  • “You Americans!” he said. “Always trying to find a use for something.” Location: 2379
  • In preparing for his oral qualifying examination, a rite of passage for every graduate student, he chose not to study the outlines of known physics. Instead he went up to MIT, where he could be alone, and opened a fresh notebook. On the title page he wrote: Notebook Of Things I Don’t Know About. Location: 2392
  • When he told a university dean that his fiancée was dying and that he wanted to marry her, the dean refused to permit it and warned him that his fellowship would be revoked. Location: 2493
  • Not so much as a grain of uranium 235 existed in pure form. Location: 2510
  • In one way or another, by the time the United States entered the war in December, one-fourth of the nation’s seven-thousand-odd physicists had joined a diffuse but rapidly solidifying military-research establishment. Location: 2537
  • Graduate students were being pressed into service with the help of a simple expedient—Princeton called a halt to most degree work. Location: 2585
  • To physicists Oppenheimer’s command of Sanskrit seemed a curiosity; to General Groves it was another sign of genius. Location: 2908
  • If Feynman says it three times, it’s right. Location: 3029
  • the Bethe Bible, the three famous review articles on nuclear physics, had provided the entire content of MIT’s course. Location: 3061
  • Cosmic rays alone sparked enough fission to make uranium 235 noticeably hotter in the high altitudes of Los Alamos than in sea-level laboratories. Location: 3075
  • He told them he could spot wrong results even when he had no idea what was right—something about the smoothness of the numbers or the relationships between them. Location: 3223
  • “It’s twenty-three hundred and four. Don’t you know how to take squares of numbers near fifty?” Location: 3240
  • Bethe knew instinctively, as did Feynman, that the difference between two successive squares is always an odd number, the sum of the numbers being squared. Location: 3245
  • He had simply added the first four terms in his head—that was enough for two decimal places. Location: 3259
  • The manufacturers of such equipment—the International Business Machines Corporation already preeminent among them—considered the scientific market to be negligible. Location: 3286
  • “He is a second Dirac,” Wigner said, “only this time human.” Location: 3385
  • People are predictable. They tend to leave safes unlocked. They tend to leave their combinations at factory settings such as 25-0-25. They tend to write down the combinations, often on the edge of their desk drawers. They tend to choose birthdays and other easily remembered numbers. Location: 3482
  • Experimentalists assembled perfect shining cubes of uranium into near-critical masses by hand. Location: 3618
  • Feynman’s first visit to Oak Ridge was his first ride on an airplane, and the thrill was heightened by his special-priority military status on the flight, with a satchel of secret documents actually strapped to his back under his shirt. Location: 3674
  • When he comes in, tell him Johnny von Neumann called.) Location: 3726
  • He estimated that a Hiroshima bomb in mass production would cost as much as one B-29 superfortress bomber. Its destructive force surpassed the power of one thousand airplanes carrying ten-ton loads of conventional bombs. Location: 3747
  • Before the war the government had paid for only a sixth of all scientific research. By the war’s end the proportions had flipped: only a sixth was financed by all nongovernment sources combined. Location: 3811
  • To have worked on the bomb gave a scientist a stature matched only by the Nobel Prize. By comparison it was nothing to have created radar at the MIT Radiation Laboratory, though by a plausible calculus radar had done more to win the war. Location: 3816
  • Unlike most of the Ivy League universities, Cornell had accepted women as undergraduates since its founding, after the Civil War, though they automatically matriculated in the College of Home Economics. Location: 3870
  • Feynman’s spacecraft would use the outer edges of the earth’s atmosphere as a sort of warm-up track and accelerate as it circled the earth. Location: 3983
  • Cornell’s 1946 fall-term enrollment was its largest ever, nearly double prewar levels. Location: 4022
  • Dyson’s war could hardly have been more different from Feynman’s. The British war organization wasted his talents prodigiously, assigning him to the Royal Air Force bomber command in a Buckinghamshire forest, where he researched statistical studies that were doomed, when they countered the official wisdom, to be ignored. The futility of this work impressed him. He and others in the operational research section learned—contrary to the essential bomber command dogma—that the safety of bomber crews did not increase with experience; that escape hatches were too narrow for airmen to use in emergencies; that gun turrets slowed the aircraft and bloated the crew sizes without increasing the chances of surviving enemy fighters; and that the entire British strategic bombing campaign was a failure. Location: 4293
  • Dyson saw the scattershot bomb patterns in postmission photographs, saw the Germans’ ability to keep factories operating amid the rubble of civilian neighborhoods, worked through the firestorms of Hamburg in 1943 and Dresden in 1945, and felt himself descending into a moral hell. Location: 4300
  • “Other people publish to show how to do it, but Julian Schwinger publishes to show you that only he can do it.” Location: 4750
  • Caltech made itself the American center of systematic earthquake science; one of its young graduates, Charles Richter, devised the ubiquitous measurement scale that carries his name. Location: 5094
  • The school moved quickly into aeronautic science, and a group of enthusiastic amateurs firing off rockets in the hills about the Rose Bowl became, by 1944, the Jet Propulsion Laboratory. Location: 5096
  • You have only told what a word means in terms of other words. Location: 5140
  • Science is a way to teach how something gets to be known, what is not known, to what extent things are known (for nothing is known absolutely), how to handle doubt and uncertainty, what the rules of evidence are, how to think about things so that judgments can be made, how to distinguish truth from fraud, and from show. Location: 5154
  • susurrus Location: 5247
  • The main rule is to treat the women with disrespect. Location: 5258
  • noetic Location: 5264
  • The year before, Schrieffer had listened intently as Feynman delivered a pellucid talk on the two phenomena: the problem he had solved, and the problem that had defeated him. Schrieffer had never heard a scientist outline in such loving detail a sequence leading to failure. Location: 5502
  • It fell to Schrieffer to transcribe Feynman’s talk for journal publication. He did not quite know what to do with the incomplete sentences and the frank confessions. He had never read a journal article so obviously spoken aloud. So he edited it. But Feynman made him change it all back. Location: 5510
  • a Caltech experimenter told Feynman about a result reached after a complex process of correcting data, Feynman was sure to ask how the experimenter had decided when to stop correcting, and whether that decision had been made before the experimenter could see what effect it would have on the outcome. Location: 5561
  • Sometimes it was not clear whether Feynman’s lightning answers came from instantaneous calculation or from a storehouse of previously worked-out—and unpublished—knowledge. Location: 5753
  • The Chicago astrophysicist Subrahmanyan Chandrasekhar independently produced Feynman’s result—it was part of the work for which he won a Nobel Prize twenty years later. Feynman himself never bothered to publish. Location: 5759
  • “I am suggesting that anyone who is transcendentally great as a scientist is likely also to have personal qualities that ordinary people would consider in some sense superhuman.” Location: 5780
  • So many of his witnesses observed the utter freedom of his flights of thought, yet when Feynman talked about his own methods he emphasized not freedom but constraints. Location: 5912
  • “The gravitational force is weak,” he said at one conference, introducing his work on quantizing gravity. “In fact, it’s damned weak.” At that instant a loudspeaker demonically broke loose from the ceiling and crashed to the floor. Feynman barely hesitated: “Weak—but not negligible.” Location: 6435
  • There is a great deal of “activity in the field” these days, but this “activity” is mainly in showing that the previous “activity” of somebody else resulted in an error or in nothing useful or in something promising. Location: 6469
  • He talked about DNA (fifty atoms per bit of information) and about the capacity of living organisms to build tiny machinery, not just for information storage but for manipulation and manufacturing. Location: 6498
  • He concluded by offering a pair of one-thousand-dollar prizes: one for the first microscope-readable book page shrunk 25,000 times in each direction, and one for the first operating electric motor no larger than a 1/64th-inch cube. Location: 6505
  • Learn by trying to understand simple things in terms of other ideas—always honestly and directly. Location: 6533
  • Then when you have learned what an explanation really is, you can then go on to more subtle questions. Location: 6535
  • If, in some cataclysm, all of scientific knowledge were to be destroyed, and only one sentence passed on to the next generation of creatures, what statement would contain the most information in the fewest words? I believe it is the atomic hypothesis (or the atomic fact, or whatever you wish to call it) that all things are made of atoms—little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another. Location: 6557
  • What we really cannot do is deal with actual, wet water running through a pipe. That is the central problem which we ought to solve some day. Location: 6593
  • “I’ve spoken to some of those students in recent times, and in the gentle glow of dim memory, each has told me that having two years of physics from Feynman himself was the experience of a lifetime.” Location: 6643
  • As the course wore on, attendance by the kids at the lectures started dropping alarmingly, but at the same time, more and more faculty and graduate students started attending, so the room stayed full, and Feynman may never have known he was losing his intended audience. Location: 6645
  • Nature uses only the longest threads to weave her pattern, so each small piece of the fabric reveals the organization of the entire tapestry. Location: 6689
  • “None of the entities that appear in fundamental physical theory today are accessible to the senses. Even more … there are phenomena that apparently are not in any way amenable to explanation in terms of things, even invisible things, that move in the space and time defined by the laboratory.” Location: 6700
  • “Questions about a theory which do not affect its ability to predict experimental results correctly seem to me quibbles about words.” Location: 6707
  • What can you explain that you didn’t set out to explain? Location: 6752
  • I’m not answering your question, but I’m telling you how difficult a why question is. You have to know what it is that you’re permitted to understand … and what it is you’re not. Location: 6779
  • I really can’t do a good job—any job—of explaining the electromagnetic force in terms of something you’re more familiar with, because I don’t understand it in terms of anything else that you’re more familiar with. Location: 6792
  • He told reporters that he planned to spend his third of the $55,000 prize money to pay his taxes on his other income (actually he used it to buy a beach house in Mexico). Location: 6952
  • “If you give more money to theoretical physics,” he added, “it doesn’t do any good if it just increases the number of guys following the comet head. So it’s necessary to increase the amount of variety … and the only way to do it is to implore you few guys to take a risk with your lives that you will never be heard of again, and go off in the wild blue yonder and see if you can figure it out.” Location: 7004
  • Dr. Crick thanks you for your letter but regrets that he is unable to accept your kind invitation to:
    ☐ send an autograph
    ☐ help you in your project
    ☐ provide a photograph
    ☐ read your manuscript
    ☐ cure your disease
    ☐ deliver a lecture
    ☐ be interviewed
    ☐ attend a conference
    ☐ talk on the radio
    ☐ act as chairman
    ☐ appear on TV
    ☐ become an editor
    ☐ speak after dinner
    ☐ write a book
    ☐ give a testimonial
    ☐ accept an honorary degree
    Location: 7011
  • I. I. Rabi once said that physicists are the Peter Pans of the human race. Feynman clutched at irresponsibility and childishness. He kept a quotation from Einstein in his files about the “holy curiosity of inquiry”: “this delicate little plant, aside from stimulation, stands mainly in need of freedom; without this it goes to wrack and ruin without fail.” Location: 7077