Why We Touch Our Mouths So Much: Evidence From Ants

In a recent post I proposed that we touch our mouths so much to transfer germs from our hands to our immune system. It’s an early warning system. The full sequence is: 1. Hands. 2. Skin around mouth. 3. Tongue (lick lips). 4. Tonsils (immune system). Forewarned is forearmed: exposure to a tiny amount of Germ X makes you much more likely to survive exposure to a large amount of Germ X.

Ants have a similar early-warning system, says a new study described here.

Cremer and her colleagues began by investigating how nestmates encountering an infected ant acted. They infected Lasius neglectus ants with Metarhizium anisopliae, a fungus that sticks to the insects’ outer cuticles and causes infection only after it has worked its way into the body, which takes a day or more. The researchers then placed infected or non-infected ants in a box with five nestmates, and watched what happened. . . .  Ants without the spores were groomed at a constant rate over 5 days, while Cremer saw a spike in grooming of the fungus-infected ants in the first day or two of infection, suggesting that the pathogen was prompting a behavior change in the nestmates.

The grooming was protective:

But even though they’d been exposed, only 2 percent of nestmates died from fungal infections, even though half of the initially infected ants, which had been dipped in solvent with M. anisopliae spores, died within 5 days. When ants were exposed to a dose of fungus expected to cause a 2 percent death rate, Cremer’s group saw an increase in antifungal activity, suggesting that this low level of infection was indeed enough to stimulate a protective immune response.

Earlier studies had shown what is called “social immunization” (“a protection of naive individuals of a colony after social contact to exposed individuals”) among insects. This study was about how social immunization happens.

After I thought of this explanation of mouth touching, I became much less concerned about contact with sick people. I hadn’t known about social immunization.

Carl Willat Suffers From the Willat Effect

Carl Willat, for whom the Willat Effect is named, wrote to me:

I had two cartons of half and half in the fridge, neither had reached its expiration date but one was three days newer. I wondered if I could taste the difference between them, and I found that I could. Neither was sour, but one tasted fresher. I made a batch of vanilla ice cream out of each of them, figuring that together with the other ingredients I was adding (vanilla, egg yolks, cream, salt and sugar) the difference in taste would be less noticeable. After putting both mixtures through the ice cream freezer I tasted them [side by side] and one tasted a lot better. I gave a friend of mine a spoonful of each and she immediately noticed the difference. She correctly identified the good one and described it as tasting fresher and lighter. I can’t bear to eat the less good batch and I don’t know what to do with it. I don’t want to give it away for fear someone will think it representative of what my ice cream tastes like. I’m sure in the past I’ve made plenty of ice cream of this same quality that I and everyone else thought was perfectly acceptable, even delicious.

The fascinating part is “can’t bear to eat the less good batch”. Same thing with me and tea: In the last half year or so, I’ve made hundreds of side-by-side comparisons of tea. I now throw away cups of tea I don’t like. I never used to do that.

Why Language Began: Words Say What We Want

My theory of human evolution posits that many features of human nature began because they increased specialization and trade. One is language. Language began with single words, I assume. The use of single words began and grew because they helped the two sides of trade find each other. The first language, in other words, was the first advertising. Advertising has two sides: (a) saying what you have too much of and (b) saying what you have too little of.

Single words are still used this way. Stores are often adorned with single words that say what they sell. When you go to an unfamiliar store, you may use single words to find what you want (“thermometers?”). The use of single words to convey desires is clear in a paper by Alexander Graham Bell, which I learned about from Electric Universe by David Bodanis. Bell (the inventor of the telephone) was a teacher of the deaf and wrote a paper about teaching deaf children language. His method involved labeling objects around the house with their names. One of his students was a five-year-old boy:

One morning he came downstairs in high spirits, very anxious to play with his doll. He frantically beat his shoulder with his hands, but I could not understand what he meant. I produced a toy-horse; but that was not what he wanted. A table; still he was disappointed. . . . At last, in desperation, he went to the card-rack, and, after a moment’s consideration, pulled out the word “doll” and presented it to me.

For a different view of why language evolved, see this paper by Hauser, Chomsky and Fitch.

Christmas: An Evolutionary Explanation (repost)

I wrote this five years ago. Perhaps it is a holiday tradition to repost old posts about the deadweight loss of gifts.

In a kitchenware store a few years ago I came across the Rotary Nutcracker, a futuristic-looking device that cracks nuts in a new way. The girl at the cash register gave me a few walnuts to test it. It didn’t crack any of them. This was a curious product, I thought. Who would buy it? The salesperson told me that they’d stocked it for less than a year. I was the first person to test it. It had sold well during holiday season. Now I understood: people didn’t buy it for themselves, they bought it as a gift. As a gift, it mattered much less how well it worked — “it’s the thought that counts.” No wonder I was the first to test it.

Here, I saw, was my theory of human evolution in . . . well, a nutshell. Part of it. Humans are the only animals with occupational specialization — we specialize, and trade. It started with hobbies. Hobbies became part-time jobs. Part-time jobs became full-time jobs. To support full-time jobs — to generate enough demand for the products of this or that specialization — there has to be enough expertise, which builds up slowly. To build up expertise, our brains changed so as to cause creation of special events like Christmas, Japanese New Year, Spring Festival (in China), and a thousand other examples around the world. Such events increase the demand for high-end craftsmanship, thus helping the most skilled craftsmen — the ones most likely to advance the state of their art — make a living. Christmas increases the demand for Christmas cards (fine printing) and Christmas-tree ornaments, for example. Traditional gift-giving has the same effect: It increases demand for “the better things in life.” Most gifts, if you follow the usual norms, are (a) not something you would buy for yourself and (b) not something the recipient would buy. (As Alex Tabarrok has noticed.) They are harder to make — and thus reward skilled craftsmen more — than the stuff we buy for ourselves, just as Christmas ornaments are harder to make than common household objects and Christmas-card printing is more difficult than most printing. Weddings, with the gifts, finery, invitations, etc., are another example. The Rotary Nutcracker didn’t work in my tests but it almost worked. If enough people bought it as a gift, that would finance the research needed to improve it.

Marginal Revolution and James Surowiecki have recently written about the “deadweight loss of Christmas” — about how gifts tend to be worth less than their cost. I think they see this as bad thing but I see it as a good thing — at least, in our evolutionary past it was a good thing. Deadweight loss = research grant. Likewise, the denizens of The Devil Wears Prada appear slightly defensive about the social value of fashion. They seem to believe that fashion is less useful than “curing cancer” (by which they mean doing research to learn how to cure cancer). Actually, high fashion, with its hard-to-make skirts, belts, and accessories, is the same as curing cancer — they’re two ways of increasing the human skill set. Art is the old Science.

Assorted Links

  • Harvard professors behaving badly: Alan Dershowitz. “In a phone interview Dershowitz denied writing to the Governor [of California], declaring, “My letter to the Governor doesn’t exist.” But when pressed on the issue, he said, “It was not a letter. It was a polite note.”” Dershowitz wrote the Governor of California to try to keep the University of California Press from publishing Beyond Chutzpah by Norman Finkelstein, which calls The Case for Israel by Dershowitz “among the most spectacular academic frauds ever published on the Israel-Palestine conflict”. Finkelstein’s book says nothing about whether Dershowitz actually wrote it. According to a statement from the UC Press, “[Finkelstein] wondered why Alan Dershowitz, in recorded appearances after [The Case For Israel] was published, seemed to know so little about the contents of his own book.”
  • Umami Burger takes Manhattan.
  • The trouble with measuring students on only one dimension: South Korea
  • Why do twins differ? Both twins have autism spectrum disorder, but one has the disorder much more than the other. Guess which one  was “given powerful drugs to battle an infection”?

Taobao Cashes In on Singles Day

All cultures, as far as I know, have festivals and special celebratory days. At least they are extremely widespread — I believe they have a genetic basis. The underlying genes evolved because they increased sales of high-end “useless” stuff. This helped skilled artisans — a big source of technological innovation — make a living. Economists speak of the “deadweight loss” of Christmas because people buy stuff that would otherwise not be bought.

China retail giant Taobao (like Ebay, except better) has shown a shrewd understanding of the festival/shopping link. On Chinese campuses since the 1970s there has been a joke holiday called Singles Day (11-11). For people who are not in a relationship. In 2010 Taobao started having a sitewide sale on that day. This year total sales were $500 million. One retailer, one day. (For comparison, all US online retail sales for the 2010 holiday season were $33 billion.) No crowds, no difficulty parking, no long lines. Still stressful, yes, but in a good way: “This is so exciting – a war and a carnival at the same time,” said one shopper.


Danny Kahneman’s Decision Making

A lovely article by Michael Lewis about Daniel (“Danny”) Kahneman, my former Berkeley colleague, emphasizes his indecision whether to write a popular book about his work. Should I or shouldn’t I? He doesn’t like what he’s written so far. Finally he decides to pay some experts for their opinion:

He called a young psychologist he knew well and asked him to find four experts in the field of judgment and decision-making, and offer them $2,000 each to read his book and tell him if he should quit writing it. “I wanted to know, basically, whether it would destroy my reputation,” he says. He wanted his reviewers to remain anonymous, so they might trash his book without fear of retribution. The endlessly self-questioning author was now paying people to write nasty reviews of his work. The reviews came in, but they were glowing.

Uh, why would anonymous experts trash his book? They gain in two ways from having it published: 1. It draws attention to their field, making them more important. 2. They can use it as a textbook. I love that Michael Bailey wrote The Man Who Would Be Queen (pdf). It allows me to assign my students a book I admire.

I think Danny has raised two great questions here:

  1. How can we set up a situation so that others will tell us the truth (= what they actually think)?
  2. How can we tell if we’ve succeeded — if they’ve told the truth?

The answers aren’t obvious, at least to me. The best answer I can give to Question 1 (what situation?) is write a blog. I take positive and negative comments to be what their authors actually think.  Variations on Question 1 are common. my recent post about E-Cat was  poorly-informed (unintentionally). The comments quickly and overwhelmingly said so. That supports my belief. In contrast to Question 1, Question 2 is rare.

The last time I talked to Danny was in the 90s. I was thinking of writing a book based on my introductory psychology lectures. I wrote a sample chapter based on my possessiveness lecture. The center of that lecture was the endowment effect (we value what we possess much more than the same thing when we do not possess it). Danny had written about it and loss aversion is part of prospect theory. By then Danny was at Princeton. I spoke to him on the phone. Does the endowment effect affect your everyday life? Does it affect what you do?  I asked. He thought about it.  No, he said. Or at least he couldn’t think of examples. In contrast, Richard Thaler chatted happily about the everyday implications.

One everyday sign of the endowment effect is a car in front of a big garage. The car isn’t in the garage because the garage is full of “junk”. Another is garage sales (also called yard sales). Such sales are held when the clutter becomes unbearable. They illustrate the everyday relevance of the effect. My point isn’t that Danny was unobservant, it’s the difference between his answer and Thaler’s. There is definitely room for two answers to my question. Humans are traders. We specialize and trade. This is central to economic life. Early papers about the endowment effect (I haven’t looked at recent papers) didn’t notice the problem/puzzle. How can we both (a) hold on to stuff tightly (= the endowment effect, loss aversion) and (b) trade easily?  John List noticed.

My friend Michel Cabanac, whose research was behind the Shangri-La Diet, has criticized Danny. In a book (p. 140), Michel wrote:

At a lecture in Jerusalem on January 19, 2001, he [Danny] was kind enough to inform the audience that the recent reorientation of his research toward what he calls “experienced utility,” which he acknowledged to be a synonym of pleasure, had been inspired by my 1993 lecture at Princeton University and by previous readings of my publications on pleasure.

In an email he elaborated:

However the “lecture” [at Princeton] was a only an invited seminar in his laboratory with an audience limited to him and his team. If I remember well, he reimbursed my travel and housing expenses. Yet, the Jerusalem mentioning of my contributions was only verbal [i.e., spoken], as I failed and still fail to find reference to Cabanac in his publications.

Michel’s whole research career has centered on the idea that pleasure guides our actions,  including “cognitive” ones. Faced with an arithmetic problem (2 + 7 = ?), for example, some answers will seem more pleasant than others. (2 + 7 = 9 is more pleasant than 2 + 7 = 10, not just more familiar.) He has especially stressed that changes in pleasure — the same events become more or less pleasant — help us self-regulate. We stop eating when food becomes unpleasant, for example. The food stays the same, we change. No one has understood the role of pleasure — which is at the center of all human decision making  — better than Michel.

When I get a copy of Danny’s new book, Thinking Fast and Slow, I will be curious to see what he says about the endowment effect, loss aversion, and Michel Cabanac.

More  Via scrbd, I have found that Danny’s new book does reference Michel — see p. 488. And, in a chapter about the endowment effect, I found this: “Knetsch, Thaler, and I set out to design an experiment that would highlight the contrast between goods that are held for use and for exchange.”  He goes on to discuss List’s research. I am unable to find anything like the phrase “the contrast between goods that are held for use and for exchange” in the paper that the three of them wrote about the effect. Jack Knetsch began to study the effect because different ways of trying to establish the value of the environment (e.g., clean water) produced enormously different answers. The endowment-effect chapter is weak on everyday examples — nothing about garage sales — but does include an unsourced quote: “She didn’t care which of the two offices she would get, but a day after the announcement was made, she was no longer willing to trade. Endowment effect!”

Thanks to Dave Lull, who suggested online searching.

The Willat Effect: More Consequences

A month ago I bought three identical tea pots to compare tea side by side. I hoped to take advantage of the Willat Effect (side-by-side comparisons create connoisseurs) to become a tea connoisseur.

It worked. Side-by-side tea comparisons are fun, easy, and have taught me a lot. When I drink tea I notice more and like it more. I do about three comparisons per day. I blogged about the first results here. The most useful idea about these comparisons came from Carl Willat himself: Compare the same tea brewed differently (e.g., different amounts of tea, different brewing times, different water temperatures). Most of my comparisons vary amount of tea or brewing time.

These many  comparisons have had several effects: Continue reading “The Willat Effect: More Consequences”

Even More About The Willat Effect

I have had tea daily for the last ten years, ever since I discovered the Shangri-La Diet. A few weeks ago, I started doing side-by-side comparisons of similar teas or the same tea prepared two ways (e.g., different brewing times). Would the Willat Effect make me a tea connoisseur?

Since then I have done at least one side-by-side comparison every day. It’s almost as easy as making an ordinary cup of tea and a lot more fun. These comparisons have taught me more about tea preparation than the previous ten years. I’ve learned:

1. The black tea I have (an Earl-Grey variant) tastes better when brewed for 3.5 minutes than 4.0 minutes.

2. The black tea tastes better when I use 1.5 grams of tea than when I use 2.0 grams of tea. (After starting these comparisons, I bought a scale for weighing tea.)

3. One of the green teas I have tastes better when “rinsed” for 30 seconds before brewing 1 minute than when simply brewed for 1 minute. In China, this preference (rinse green tea before brewing) is common. I was reminded of it by this comment and Paul Jaminet’s post about tea. Black tea is different, as I noted earlier.

4. I have a caffeine-free tea blend called Choco Late made of cacao husks, vanilla, and rooibos. The package says brew 5 minutes. Which is nonsense. It tastes better (fuller, more rounded) when brewed 30 minutes than when brewed 15 minutes. (I’ve noticed the same thing with caffeine-free chai blends. Enormous brewing times, like 60 minutes, produce much better results than short times.)

5. My most interesting discovery is when I brew Choco Late for 30 minutes it tastes so good I no longer want to sweeten it. It is pleasant enough already and sweetness would distract from the complexity, fullness, and slight bitterness. (At first I wrote “lovely complexity, fullness …”) I was shocked when I noticed this. It has never happened before.

This tea-selling website mentions the Willat Effect under the heading “Do you want to be a tea connoisseur?” I hope this means the idea will spread among the fancy-food community. They have a lot to gain from better understanding of how to make people connoisseurs. Many times I have asked people in that community what makes someone a connoisseur? The usual answer is education. In my case, Willat-Effect comparisons (side-by-side comparisons of similar teas) were far more powerful than reading about tea, drinking a variety of teas, going on tea tours, going to ordinary tea tastings (where you taste a wide range of teas), and talking about tea with experts. I have been to five or six Fancy Food Shows and have visited thousands of booths. Exactly one booth offered side-by-side comparisons of similar products. It was their product made with and without a special ingredient.

Willat-Effect comparisons are mini-science. They aren’t quantitative but they include three other things central to science: 1. Close comparisons. This is the essence of experimentation. 2. You don’t know the answer. 3. You care about the answer.

More About The Willat Effect

The Willat Effect is the hedonic change produced by side-by-side comparisons of similar products — for example, two green teas. It happens in seconds: Suddenly the differences matter more. Some versions become more pleasant, other versions less pleasant.  I first noticed it with limoncello that my friend Carl Willat offered me. Here are some reactions to my recent post about it: Continue reading “More About The Willat Effect”

Willat Effect Experiments With Tea

The Willat Effect is the hedonic change caused by side-by-side comparison of similar things. Your hedonic response to the things compared (e.g., two or more dark chocolates) expands in both directions. The “better” things become more pleasant and the “worse” things become less pleasant. In my experience, it’s a big change, easy to notice.

I discovered the Willat Effect when my friend Carl Willat offered me five different limoncellos side by side. Knowing that he likes it, his friends had given them to him. Perhaps three were homemade, two store-bought. I’d had plenty of limoncello before that, but always one version at a time. Within seconds of tasting the five versions side by side, I came to like two of them (with more complex flavors) more than the rest. One or two of them I started to dislike. When you put two similar things next to each other, of course you see their differences more clearly. What’s impressive is the hedonic change.

The Willat Effect supports my ideas about human evolution because it pushes people toward connoisseurship. (I predict it won’t occur with animals.) The fact that repeating elements are found in so many decorating schemes and patterns meant to be pretty (e.g., wallpapers, textile patterns, rugs, choreography) suggests that we get pleasure from putting similar things side by side — the very state that produces the Willat Effect. According to my theory of human evolution, connoisseurship evolved because it created demand for hard-to-make goods, which helped the most skilled artisans make a living. Carl’s limoncello tasting made me a mini-connoisseur of limoncello. I started buying it much more often and  bought more expensive brands, thus helping the best limoncello makers make a living. Connoisseurs turn surplus into innovation by giving the most skilled artisans more time and freedom to innovate.

Does the Willat Effect have practical value? Could it improve my life? Recently I decided to see if it could make me a green tea connoisseur. Ever since I discovered the Shangri-La Diet (calories without smell), I’d been drinking tea (smell without calories) almost daily but I was no connoisseur. Nor had I done many side-by-side comparisons. At home, I had always made one cup at a time.

In Beijing, where I am now, I can easily buy many green teas. I got three identical tea pots (SAMA SAG-08) and three cheap green teas. I drink tea every morning. Instead of brewing one pot, I started making two or three pots at the same time and comparing the results. I compared different teas and the same tea brewed different lengths of time (Carl’s idea).

I’ve been doing this about two weeks. The results so far:

1. The cheapest tea became undrinkable. I decided to never buy it again and not to drink the  rest of my purchase. I will use it for kombucha. Two of the three teas cost about twice the cheapest one. After a few side by side comparisons I liked the more expensive ones considerably more than the cheaper one. The two more expensive ones cost about the same but, weirdly, I liked the one that cost (slightly) more a little better than the one that cost less. (Tea is sold in bulk with no packaging or branding so the price I pay is closely related to what the grower was paid. The buyers taste it and decide what it’s worth.)

2. I decided to infuse the tea leaves only once. (Usual practice is to infuse green tea two or more times.)  The quality of later infusions was too low, I decided. Before this, I had found second and later infusions had been acceptable.

The Willat Effect is working, in other words. After a decade of drinking tea, my practices suddenly changed.  I will buy different teas and brew them differently. I will spend a lot more per cup since (a) each cup will require fresh tea, (b) I won’t buy the cheapest tea, and (c) I have become far more interested in green tea, partly because each cup tastes better, partly because I am curious if more expensive varieties taste better. When I bought the three varieties I have now I didn’t bother to learn their names; I identified them by price. In the future I will learn the names.

To get the Willat Effect, the things being compared must be quite similar. For example, comparing green tea with black tea does nothing. I have learned a methodological lesson: That tea is a great medium for studying this not only because it’s cheap but also because you can easily get similar tasting teas by brewing the same tea different lengths of time. I haven’t yet tried different water temperatures but that too might work.

I have done similar things before. I bought several versions of orange marmalade, did side-by-side tastings, and indeed became an orange marmalade connoisseur. After that I bought only expensive versions. After a few side-by-side comparisons of cheese that included expensive cheeses, I stopped buying cheap cheese. You could say I am still an orange marmalade and cheese connoisseur but this has no effect on my current life. Because I avoid sugar, I don’t eat orange marmalade. Because of all the butter I eat, I rarely eat cheese. My budding green tea connoisseurship, however, is making a  difference because I drink tea every day.

My posts about human evolution.

Jane Jacobs and Amazon.com

How did air-breathing evolve? In The Nature of Economies (p. 87), Jane Jacobs uses it to illustrate the developmental pattern she calls “bifurcation” (air-breathing isn’t a refinement of water-breathing). She speculates on how it started:

Lungfish had both gills and a primitive lung, suggesting that their habitat was swampland. The earliest to take to dry land may have inhabited swamps subject to severe droughts or perhaps they were escaping fearsomely-jawed predators who couldn’t follow them to dry land.

According to Steve Yegge’s already-famous “psst, Googlers” memo, something much like this was why Amazon started selling web computing services, which wasn’t a refinement of their earlier business (selling books, toys, etc.):

Amazon was a product company too, so it took an out-of-band force to make Bezos understand the need for a platform. That force was their evaporating margins; he was cornered and had to think of a way out. But all he had was a bunch of engineers and all these computers… if only they could be monetized somehow… you can see how he arrived at AWS [Amazon Web Services], in hindsight.

People say necessity is the mother of invention. That isn’t even close to true. Trial and error is the mother of true, profound invention. The Bezos story, and Jacobs’s generalization of it, suggest what is actually true: necessity is the mother of development. Necessity pushes people to use, and thereby develop, inventions they had ignored.

Chapter 1 of The Nature of Economies.

Assorted Links

Thanks to Tim Lundeen, J.C. and Ben Casnocha.

The Willat Effect: Side-by-Side Comparisons Create Connoisseurs

About ten years ago, while visiting my friend Carl Willat, he presented me with five versions of connoisseurs were important in human evolution because they helped support skilled artisans. Our design preference for repeated elements (e.g., wallpaper, textiles) evolved so that we would put similar things side by side. Continue reading “The Willat Effect: Side-by-Side Comparisons Create Connoisseurs”

Unofficial Beer Tasting Winner: Uncommon Brewers

Last night I went to a beer tasting in San Francisco. I didn’t taste all the beers but of the 15-odd I did taste the best were by Uncommon Brewers — especially their Siamese Twin (“the floral notes of lemongrass and sharper bite of kaffir lime blend with the deep malt”) and Baltic Porter (“whole licorice root and star anise”).

Five or six years ago I went to a sake-tasting event in San Francisco called “The Joy of Sake”. About 140 sakes. In a few hours I became such a sake connoisseur that the sake I could afford  — and used to buy regularly — I now despised. The only sake I now liked was so expensive ($80/bottle) that I never bought another bottle of sake.


Sterilities of Scale and What They Say About Economics

You have surely heard the phrase economies of scale — meaning that when you make many copies of something each instance costs less than when you make only a few copies. Large companies are said to benefit from “economies of scale” — so there is pressure to become bigger. Every introductory economics textbook says something like this. Continue reading “Sterilities of Scale and What They Say About Economics”

Downward Spiral of Whole Foods House Brand

whole foods balsamic vinegar

My friend Carl Willat sent me this photo with the comment “noticeably worse” — meaning that the new version (on the right) is noticeably worse than the old version (on the left). 365 is the Whole Foods house brand. Years ago,the label of 365 balsamic vinegar said “aged 5 years”. Then one day it didn’t. The younger vinegar (aged 1 year?) tasted noticeably worse. In a side-by-side comparison, it was obvious.

Side-by-side comparisons, I discovered thanks to Carl, are powerful — and I could use that power to improve my life. A long time ago at his apartment I tasted five versions of limoncello (Italian lemon liqueur) side by side. Of course the differences became clearer–that’s obvious. The surprise was that all of a sudden I cared about the differences. Before that tasting, I had had plenty of limoncello. But only at the side-by-side tasting did I develop a liking for the good stuff (more complex flavor) and a dislike for the cheaper stuff (simpler flavor). I stopped buying cheap limoncello and started buying expensive limoncello. I got a lot of pleasure out of it. I still do this. A few weeks ago I bought some rum to flavor my yogurt. I started with the cheapest brand. A week later, to compare, I got a more expensive brand. Side-by-side tasting showed it was clearly better. Now I sort of relish it — the side-by-side comparison made rum drinking more enjoyable. Soon I will get an even more expensive rum, to see how it stacks up.

I’m pretty sure such side-by-side comparisons are how connoisseurs are made. The evolutionary reason for this effect, I believe, is that connoisseurs will pay more than other people for well-made stuff, thus helping skilled artisans — during the Stone Age, the main source of innovation — make a living.

In Carl’s picture the new vinegar looks much cheaper than the old vinegar. The previous change (from aged 5 years to not aged 5 years) wasn’t accompanied by a cheaper-looking label. Maybe Whole Food headquarters had received complaints from manufacturers of other balsamic vinegars: Your house brand is too good. And they replied: Okay, we’ll cheapen it.

Danger of Low-Carb Diet: Not Enough Vitamin C

I eat a low-carb diet for reasons that have nothing to do with weight loss: To keep my blood sugar down. I am sure high blood sugar is bad. A few months ago, I noticed that my lips were chapped, which was unusual. I suspected it was due to lack of Vitamin C. About two months before that, I had stopped doing two things that I usually did: taking a multi-vitamin pill (which had Vitamin C) and eating fruit. I don’t know if the Vitamin C in the pill is absorbed but I’m sure the Vitamin C in fruit is. I started eating kumquats — the skins of four kumquats/day. (One kumquat contains about 15% of the recommended daily allowance of Vitamin C). My lips returned to normal.

Paul Jaminet, author of Perfect Health Diet, had a similar experience, which I knew nothing about when I noticed my chapped lips. While eating “a lot of vegetables but no starches and hardly any fruit,” he developed outright scurvy, including wounds that wouldn’t heal.  This happened while he was taking a multi-vitamin pill with 90 mg Vitamin C (my four kumquats contain only 35 mg Vitamin C). “Four grams a day of vitamin C for two months cured all the scurvy symptoms,” he found.

Why do we like sweet foods? The usual answer (so that we will eat more calories) is nonsense (except for children). The striking thing about our liking for sweetness is that it disappears when we are really hungry, which is the opposite of what the calorie-seeking explanation predicts. Desserts are served at the end of a meal because they taste much better then. But our liking for sweetness (when we’re not hungry) is so strong and obvious it must mean something important. I think it is pushing us to eat more fruit so that we will get enough Vitamin C. Fruits are much sweeter than other food groups and they are much higher in Vitamin C. We don’t like sweet things when we are hungry because a high-fruit diet is terrible (it is low in omega-3, other necessary fats, several minerals, and microbes, for example). But a small amount of fruit may be a big help. Paul and my experiences suggest it may be hard to get enough Vitamin C in other ways.

More Paul has a different idea about why we like sweetness.

Climate Model Predictions and What Happened

In a comment on a previous post about lack of convincing evidence for climate models — the ones that predict catastrophe — I wrote:

At any time — right now, 5 years ago, 10 years, 15 years ago –” the people who work with those models and claim we should pay attention to their predictions could make/have made a set of predictions: next year, the year after that, and so on. Then, as time passed, we would have found out if the models predict correctly. The modelers haven’t done that.

From this talk by Richard Muller, a Berkeley physicist, I learned of two instances where the modelers did what I said they haven’t done. Continue reading “Climate Model Predictions and What Happened”

Memory Palaces and the Walking/Learning Connection

In this excellent article, Joshua Foer describes how he got really good at competitive memory tests, such as remembering the order of a deck of cards. He competed in the national championships.

Foer writes a lot about using “memory palaces” to remember stuff. You take a familiar building or neighborhood and vividly imagine what you want to remember at different places within it. To retrieve the memories, you mentally visit each place.

This is an ancient and famous method. I knew about it but had not realized until I read the article that it sheds light on my discovery that treadmill walking makes learning Chinese pleasant. (A commenter named Tom also noticed the connection.) Foer gives the obvious evolutionary explanation for why the memory palace method works so well: long ago, we needed to remember where to find important stuff (water, food, special plants, useful materials). So we evolved a memory system well-suited for doing so.

Less obvious is another evolutionary idea: why stop there? It’s a system. When you design a car for a certain sort of driving, you don’t stop with the engine. You adjust the drive train, the tires, and so on. If evolution shaped our brains for a certain sort of data (things in places), surely it also shaped our brains to collect that data. Pointless to design a car no one drives.

Two more changes would help make use of the system:

1. Hedonic. Make it pleasant to fill the system with data. This is what I noticed — dry knowledge (such as the order of cards in a deck) became pleasant to learn. Long ago, the hedonic change I noticed would have pushed people to walk in new places rather than old ones.

2. Efficiency.  Make learning more efficient (= more learning per unit time). Several confounded comparisons point in this direction. For example, I found that 15 minutes studying flashcards while riding the subway was a lot less help than spending 15 minutes while walking on my treadmill. Of course there are many differences between the two situations. Likewise, using Anki is working much better now than in the past, when I used it sitting down. I will try to study this more carefully.

Years ago, evolutionary explanations such as these were mocked as “just so stories” by prominent scientists, such as Stephen Jay Gould, Noam Chomsky, and Richard Lewontin. It’s now clear they were wrong.