Learn at night and relearn in the morning

Friday, October 12th, 2018

We already know that (1) spacing practice out results in better learning and long-term retention than cramming it all together, and (2) sleep enhances learning and long-term retention.

A team of French researchers combined these two effects into a simple practice scheduling hack:

Two groups of 20 participants were tasked with learning the French translations of 16 Swahili words. All 40 participants went through the same exact training, but there was one teensy difference.

One group (“wake” group) had their first study session at 9am, and their relearning session at 9pm on the same day. The other group (“sleep” group) had their first study session at 9pm, and their relearning session at 9am the following morning.


The researchers kept track of how much practice the participants needed to get all 16 translations correct. The sleep group got to perfect recall in about half the time that it took the wake group (3.05 cycles through the list vs. 5.80 cycles). Plus, every single participant in the sleep group got a perfect score within 5 attempts, whereas 75% of the wake group needed more practice.


A full half a year later, the sleep group continued to out-remember the wake group (8.67 correct vs. 3.35).

Dementia starts in the ICU

Thursday, October 11th, 2018

Doctors are gradually realizing that a trip to the intensive care unit can lead to serious memory problems:

This dementia, a side-effect of intensive medical care, can be permanent. And it affects as many as half of all people who are rushed to the ICU after a medical emergency. Considering that 5.7 million Americans end up in intensive care every year, this is a major problem which, until recently, has been poorly appreciated by medical caregivers.


“This is a huge problem,” says Dr. E. Wesley “Wes” Ely, an intensive care specialist who heads that effort. He says post-ICU syndrome — a cluster of cognitive symptoms that can include anxiety, depression and PTSD, as well as delirium — affects 30 to 50 percent of all patients who are rushed to the ICU because of a medical emergency. That’s including younger patients who had no prior mental challenges. And in some of those patients, dementia soon follows.

“You have somebody coming into the ICU with a previously very well-working brain and they leave critical care not being able to have a good conversation,” Ely says. “They can’t balance their checkbook, they can’t find the names of people at a party and they get very embarrassed, so they start socially secluding themselves. Our patients tell us what a misery this form of dementia is.”

Ely has been tracking his patients for more than a decade through scientific studies such as the BRAIN-ICU study. He says about one third of patients who have cognitive problems following their ICU stay fully recover; another third stay about the same after their dementia sets in — and a third continue to go downhill.

For many, the damage to mental processing is akin to what’s seen with a traumatic brain injury, or in a condition called mild cognitive impairment — or even Alzheimer’s disease.

Researchers don’t yet know how the brain is changing to give rise to these symptoms, or how extended delirium leads to that brain damage; Ely is launching a large study to help tease out some of those mechanisms. What parts of the brain are affected, and how does the damage differ from that caused by other forms of dementia such as Alzheimer’s? One idea he will explore is whether tiny blood clots might be forming in the brain and playing a role the long-term damage.

In the meantime, Ely says, one thing the doctors treating these patients with sudden dementia are certain of is that their mental problems are linked to the degree of delirium they experience while in the ICU.

“Every day you’re delirious, you have about a 35 percent increased risk of this dementia,” he says. “So if you do the math on that — [after] three days of delirium, you have almost a sure thing you’re going to have some elements of the dementia.”

We are willing to suffer more to keep what we have now

Thursday, October 4th, 2018

T. Greer reviews two books by Kenneth Payne on the psychology of strategy — The Psychology of Strategy: Exploring Rationality in the Vietnam War and Strategy, Evolution, and War: From Apes to Artificial Intelligence:

Payne isolates several aspects of human psychology that are especially relevant to strategic decision making. Payne divides these aspects into three broader themes: unconscious biases that affect strategic decision making, interaction between emotions and strategic action, and the critical role that social esteem plays in the psychology of strategy.


For example, there is strong evidence humans become more certain in our beliefs and in our decisions when angry; the strategic calculations of an angry decision maker will be fundamentally different from a sorrowful one. One of the more intriguing ideas in Payne’s catalog of biases is his interpretation of Clausewitz’s dictum that the defense is stronger than the offense. This is true, Payne argues, because humans are loss averse. We are willing to suffer more to keep what we have now than we are to earn something new. If humans think about territory or international prestige this way, then commanders will be bolder when trying to recover lost ground, and their soldiers will be more determined in defense than on the attack.

The most interesting part of this discussion is Payne’s analysis of honor and esteem. Humans are social animals. The need for the esteem of other humans seems deeply ingrained in human psychology, and statesmen and strategists are not immune to this. In The Psychology of Strategy Payne provides scores of examples of strategic decisions made by Lyndon Johnson, Richard Nixon, and other officials that were made more to bolster the social esteem of the decision maker than to defeat the enemy. For Johnson and his officials, esteem and reputation were often explicitly described as the most important objective in the war — one administration official estimated in a memo that 70% of the reason the U.S. was escalating in Vietnam was to avoid humiliation; the other 30% was divided between the need to keep Vietnam out of Chinese hands and to help the people of South Vietnam live a freer life.


Esteem, emotion, and cognitive biases are human phenomena. If wars were fought by non-humans they would be fought differently. This is exactly what Payne imagines for the future of war. Artificial intelligence will be a revolution in warfare, Payne claims, because for the first time in man’s evolutionary history, strategy will be freed from the limits of human psychology: “Rather than creating a danger from AI acting strategically against humans, the main effects of AI are likely to be felt from AI acting in our interests.”

Nature has won

Sunday, September 30th, 2018

In reviewing Robert Plomin’s Blueprint: How DNA Makes Us Who We Are, Gregory Cochran says, forget Nature versus Nurture. Nature has won:

Assuming that this work is correct, what does it mean? What are the implications?

It means that we have to completely rethink and rebuild the social sciences. Steven Pinker said: “For most of the twentieth century it was assumed that psychological traits were caused by environmental factors, called nurture.” This was completely wrong. Problems like p-value fishing and the current ‘replication crisis’ are nothing compared to the tsunami that’s coming.

Indeed, social scientists have done such a terrible job that it’s hard to see how the field can be repaired. They wanted the false results they got, and they still do. I’m sure their descendants will as well. Isn’t heritability grand?

We need a different kind of social science researcher, smarter, less emotional, and more curiosity-driven. Intellects vast and cool and unsympathetic. But where will we find them?

Giving Mars a magnetosphere

Thursday, September 20th, 2018

Brandon Weigel talks about the potential for supplying Mars with an artificial magnetic field:

By placing a satellite equipped with technology to produce a powerful magnetic field at Mars L1 (a far orbit around Mars where gravity from the Sun balances gravity from Mars, so that the satellite always remains between Mars and the Sun), we could encompass Mars in the resulting magnetic sheath.

Martian Magnetosphere

Earth’s magnetic field, originating at it’s core, has a strength of ~6*10^-5 Teslas at the distance of the Earth’s surface. This is the force which deflects compass needles. It is also the strength required to defend our atmosphere against deadly solar wind. However, a space-based magnetic field at Mars does not have to be quite this powerful. First of all, our goal is only to encompass Mars in the magnetosheath of the field; it does not need to extend as far as the Earth’s does. Earth’s magnetosheath extends to ~6 million kilometers. Mars L1 is only about 1 million km from Mars. Of course, we are going to want to allow some leeway for potential solar flare events, but extending the field ~1.5 million km is probably sufficient.

Another thing to take into account is the fact that the intensity of solar wind at Mars’ distance is less than half that at 1 AU. This means that we only need a magnetic field half as powerful as what we would have needed to defend a planet at Earth’s distance from the sun. Taking both of these factors into account, a space-based magnetic field around Mars only needs to have a strength of roughly 11% that of Earth’s. This will create a magnetosheath long enough to extend 500,000 kilometers beyond Mars.

Using the magnetic field magnitude equation, we can now solve for the amperage of the “wire” required to produce such a field. This yields a current of ~200 Mega-amperes. Any electrician knows right now that we are going to need a BIG ASS wire.


Some things to note are the exceptionally low voltage for the system of about 2 volts, and the dimensions/mass of the copper solenoid which come out to a torus with a total diameter of ~3.5 meters and a mass of ~57 tonnes. This is a big copper doughnut. It would fill the average living room area wall-to-wall and weigh more than 6x the legal mass of a loaded semi truck on the freeway. A magnetic field of ~81 Teslas is generated at the surface of the solenoid; nearly twice the strength of the strongest artificial continuous magnetic field ever produced to date. Another thing to note is the fact that a fission reactor of this size will require over 40 tonnes of uranium every two years to remain in operation. This may be the biggest problem for any future Martian-magnetosphere endeavor, seeing as a launch to Mars from Earth takes about 18 months and the abundance of uranium on Mars itself is unknown.

Hamsters really do love wheels

Sunday, September 9th, 2018

Like other rodents, hamsters are highly motivated to run in wheels:

It is not uncommon to record distances of 9 km (5.6 mi) being run in one night. Other 24-h records include 43 km (27 mi) for rats, 31 km (19 mi) for wild mice, 19 km (12 mi) for lemmings, 16 km (9.9 mi) for laboratory mice, and 8 km (5.0 mi) for gerbils.

Hypotheses to explain such high levels of running in wheels include a need for activity, substitute for exploration, and stereotypic behaviour. However, free wild mice will run on wheels installed in the field, which speaks against the notion of stereotypic behaviour induced by captivity conditions. Alternatively, various experimental results strongly indicate that wheel-running, like play or the endorphin or endocannabinoid release associated with the ‘runner’s high’, is self-rewarding. Wheel use is highly valued by several species as shown in consumer demand studies which require an animal to work for a resource, i.e. bar-press or lift weighted doors. This makes running wheels a popular type of enrichment to the captivity conditions of rodents.

Captive animals continue to use wheels even when provided with other types of enrichment. In one experiment, Syrian hamsters that could use tunnels to access five different cages, each containing a toy, showed no more than a 25% reduction in running-wheel use compared to hamsters housed in a single cage without toys (except for the running wheel).

In another study, female Syrian hamsters housed with a nest-box, bedding, hay, paper towels, cardboard tubes, and branches used a wheel regularly, and benefited from it as indicated by showing less stereotypic bar-gnawing and producing larger litters of young compared to females kept under the same conditions but without a wheel. Laboratory mice were prepared to perform more switch presses to enter a cage containing a running wheel compared to several meters of Habitrail tubing or a torus of Habitrail tubing.

Running in wheels can be so intense in hamsters that it may result in foot lesions, which appear as small cuts on the paw pads or toes. Such paw wounds rapidly scab over and do not prevent hamsters from continuing to run in their wheel.

A hamster in a running wheel equipped with a generator can generate up to 500 mW electric power, enough for illuminating small LED lamps.

(Hat tip to our Slovenian Guest.)

Scientists identify a new kind of human brain cell

Friday, September 7th, 2018

Scientists have identified a new kind of human brain cell:

The research team, co-led by Lein and Gábor Tamás, Ph.D., a neuroscientist at the University of Szeged in Szeged, Hungary, has uncovered a new type of human brain cell that has never been seen in mice and other well-studied laboratory animals.

Tamás and University of Szeged doctoral student Eszter Boldog dubbed these new cells “rosehip neurons” — to them, the dense bundle each brain cell’s axon forms around the cell’s center looks just like a rose after it has shed its petals, he said. The newly discovered cells belong to a class of neurons known as inhibitory neurons, which put the brakes on the activity of other neurons in the brain.

The study hasn’t proven that this special brain cell is unique to humans. But the fact that the special neuron doesn’t exist in rodents is intriguing, adding these cells to a very short list of specialized neurons that may exist only in humans or only in primate brains.

The researchers don’t yet understand what these cells might be doing in the human brain, but their absence in the mouse points to how difficult it is to model human brain diseases in laboratory animals, Tamás said. One of his laboratory team’s immediate next steps is to look for rosehip neurons in postmortem brain samples from people with neuropsychiatric disorders to see if these specialized cells might be altered in human disease.

Every specimen is arguably irreplaceable

Thursday, September 6th, 2018

Brazil’s National Museum in Rio de Janeiro burned down, which is terrible, but not terribly surprising:

The burned building was the largest natural-history museum in Latin America, but it had never been completely renovated in its 200-year history. It had long suffered from obvious infrastructure problems including leaks, termite infestations, and — crucially — no working sprinkler system. Recognizing these problems in the 1990s, museum staff began planning to move the collection into a different site, but without stable funding, those plans proceeded in fits and starts.


The museum’s herbarium, its main library, and some of its vertebrates were housed in a different building that was untouched by the fire. But together, these reportedly account for just 10 percent of the museum’s collection. For comparison, the remaining 90 percent includes twice as many specimens as the entire British Museum. Museum staff carried out whatever they could by hand, including parts of the mollusk collection. Time will tell what else survived, and some losses are already clear: The floor beneath the entomology collection collapsed, for example, and the 5 million butterflies and other arthropods within were likely lost.

The museum’s archeological collection had frescoes from Pompeii, and hundreds of Egyptian artifacts, including a 2,700-year-old painted sarcophagus. It housed art and ceramics from indigenous Brazilian cultures, some of whose populations number only in their thousands. It contained audio recordings of indigenous languages, some of which are no longer spoken; entire tongues went up in flames. It carried about 1,800 South American artifacts that dated back to precolonial times, including urns, statues, weapons, and a Chilean mummy that was at least 3,500 years old.

Older still was the museum’s rich trove of fossils, from crocodile relatives like Pepesuchus to one of the oldest relatives of today’s scorpions. It harbored some of the oldest human remains in the Americas: the 11,500-year-old skull and pelvis of a woman who was unearthed in 1975 and nicknamed Luzia. “The skull is very fragile,” the artist Maurilio Oliveira told The New York Times. “The only thing that could have saved it is if a piece of wood or something fell and protected it.”

One might think that fossils, being rock, would be immune to fire. But as Mariana Di Giacomo, a paleontologist from the University of Delaware, described in a Twitter thread, fires can reach temperatures that are high enough to crack stone. It destroys buildings, causing walls and ceilings to fall on fragile specimens. It burns the labels attached to fossils and the numbers that are painted onto them, turning something that’s part of the scientific record into uninformative rock. “Without data, we only have old bones/shells/logs,” wrote Di Giacomo. Even the water that’s used to quench the flames can make things worse, causing fossils to swell and crack, dissolving adhesives, ruining labels even further, and stimulating the growth of mold.

The burned building housed skeletons of several dinosaurs, including Maxakalisaurus, a 44-foot-long, armor-backed, long-necked titan, and Santanaraptor, a lithe predator that contained beautifully preserved soft tissues in its legs, down to individual muscle fibers. “That really stabs me in the heart as a scientist,” said John Hutchinson from the Royal Veterinary College. “I always wanted to go study that specimen. It could have been revelatory. Now that probably will be impossible for anyone.”

The museum was also home to an irreplaceable collection of pterosaurs — flying reptiles that soared over the dinosaurs’ heads. Brazil was something of a “heaven for pterosaurs,” and the discovery of spectacular creatures such as Tapejara, Tupandactylus, and Tupuxuara, with their marvelously complete skeletons and improbably ornate crests, helped to reshape our understanding of these animals. “We may have lost dozens of the best preserved pterosaurs in the world,” said the paleontologist Mark Witton. “There really is no collection comparable … We find them elsewhere in the world, but the quality of the Brazilian material is remarkable.”

Many of these presumably lost specimens were holotypes — the first, best, and most important examples of their kind. Every specimen is arguably irreplaceable, but holotypes are especially so. Losing them is like losing the avatar of an entire species. Some of these specimens have been drawn and described in the scientific literature, but that information is often patchy, which is why scientists frequently return to holotypes to study them with their own eyes.

I’m reminded of all the Middle Eastern artifacts housed in London — where they’re a good deal safer.

Fitbit heart data reveals its secrets

Monday, September 3rd, 2018

Fitbit has now logged 150 billion hours’ worth of heart-rate data from tens of millions of people, all over the world:

Fitbit Heart Data 1 Resting Heart Rate by Age

Fitbit Heart Data 2 BMI vs. HR by Gender

Fitbit Heart Data 3 Resting Heart Rate with Exercise

Fitbit Heart Data 4 Activity Effect on Resting Heart Rate by Age

Fitbit Heart Data 5 Resting Heart Rate with Sleep

Fitbit Heart Data 6 Activity vs. Heart Rate by Country

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!

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.

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

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