Adam Victor Brandizzi

Summer is upon us and you are almost certainly planning at least one trip to the beach. This year, as you lie back in the sun, put down your book or magazine and sift the sand through your fingers - and take a moment to reflect upon how much of the world economy is built on the stuff.

I don't mean "built on sand" in a philosophical sense, however true that may be. I'm talking about three technological revolutions that are literally based on sand, one of which is only just beginning and, if it lives up to its potential, has mind-boggling implications.

You've probably already guessed the element at the heart of these revolutions - silicon, the main component of sand.

The original silicon revolution was of course, glass. Man first began to explore its properties a million and a half years ago - that's when our ancient ancestors discovered that obsidian, the almost jet black glass which is sometimes formed when lava cools rapidly, was useful.

Obsidian breaks leaving a very keen edge, so was good for weapons and tools including, in some ancient cultures, knives used for ritual circumcisions.

But it wasn't until the first civilizations arose in the plains of Mesopotamia that we learned to actually make glass.

The recipe is simple, but must be followed carefully. The main ingredient, silicon dioxide or silica, is everywhere. Three-quarters of the earth's crust is made up of this compound of oxygen and silicon. Silica is the basis of most rocks, the reason they all seem so different is because of the different processes by which they are formed and the different crystals silica creates with other compounds.

Having got your silica, usually in the form of sand, you heat it until it melts - about 1,600C. You melt in a little soda ash and dash of limestone and then cool the mixture fairly quickly.

With any luck - and it has taken 5,000 years to perfect the process - you'll have created an "amorphous solid", which is what glass is.

What that means is that the atoms in glass are locked in place but, instead of forming neat orderly crystals, they are arranged randomly - so glass is rigid, like a solid, but has the disordered arrangement of molecules of a liquid.

Once we'd discovered we could create this incredible tough-but-see-through stuff there was no stopping us. Think what life would be like without glass windows, windscreens and bottles and what would the world's scientists do without the lenses in their microscopes or telescopes?

Flemish or German miniature depicting a 15th Century glass-blowing factory

And chemistry is very dependent on glass too, as Prof Andrea Sella of University College London - the king of our chemical sandcastle - was keen to point out as I make my now ritual visit to his lab.

He ushers me into the university's glass workshop, where the glass beakers and burettes, and test tubes and pipettes, are created by UCL's glassblower-in-chief, John Cowley. But while he inflates a spectacular ball flask over a roaring gas jet, Sella explains that the next silicon revolution was based on a very different form of the element.

We are talking, of course, about the computing revolution driven by microprocessors etched into silicon chip. The silicon in these chips uses silica that has been stripped of its two oxygen molecules and refined into one of the purest materials on the planet.

Sella pulls a silver-grey metallic-looking lump from a box by his side. It is, he tells me with a note of awe in his voice, 99.9999999% pure silicon - the standard level of purity in the microprocessor industry.

But why silicon?

The answer is the fact that it is a semiconductor - a substance whose electrical conductivity can be manipulated. Computer chips are in essence tiny assault courses for electrons.

"The whole of the semiconductor industry," explains Sella, "is based on deliberately adding impurities to tweak the behaviour of the silicon. These impurities create tiny obstacles for the electrons to negotiate. You can turn the obstacles on and off to tweak the behaviour of the electrons and vast numbers of these obstacles allow us to do all of the logic functions associated with a computer processor."

The obstacles are known as transistors.

The first integrated circuit - as computer chips were originally known - was a relatively simple affair. It was created by an engineer named Jack Kilby at Texas Instruments and demonstrated on 12 September 1958. Kilby's chip was made of germanium, another semiconducting element.

But within months a team led by Robert Noyce at a rival company, Fairchild Electronics, created a chip based on silicon. The entire modern computing industry can trace its lineage back to this one chip, though modern chips are millions of times more complex.

Indeed, the miracle of the modern microprocessor is the vast number of transistors the industry has learned to pack on to a tiny wafer of silicon. It's why even tiny devices can have incredible computing power these days.

It was a colleague of Noyce's, Robert Moore, who first realised how quickly the power of computers would multiply. A few years after that first silicon chip was created, he predicted that the number of transistors on a chip would double roughly every two years.

Even he didn't expect what became known as Moore's Law to hold for more than a couple decades, but it has - thanks, in good part, to the innovations of company that he and Noyce founded, Intel, the biggest computer chip manufacturer in the world in terms of revenue.

In the company's in-house museum there is a display that graphically illustrates Moore's law in action. The first chip, produced in 1969, contains 1,200 transistors. By 1972 that had almost doubled to 2,500. It went on doubling and then doubling again - Intel's latest chips have two billion transistors or more packed on to a single tiny chip of silicon - and almost 50 years after he first formulated his law we are still asking how long this incredible miniaturisation can continue.

"I've been in the industry long enough to remember when the experts were saying you cannot make devices smaller than 100 nanometres," says Mark Bohr, the man in charge of working out how Intel can pack even more transistors on to even smaller slices of silicon. "Now we are making devices that are 10 nanometres in size and we don't see an end to it yet."

To give you a sense of scale, a human red blood cell is about 4,000 nanometres across.

But he admits that operating at this nano scale does produce weird and fascinating new challenges. One is a phenomenon called "quantum tunnelling". That happens when the circuits are so small that you can't say with any certainty where an electron is, you can only attach a probability to where it might be.

It means electrons "jump" or "tunnel" across all those carefully created obstacles. And this creates all sorts of problems. It can lead to power draining or "leaking" from chips, it can stop your chip working at all, and it can make your chips get very hot.

In response, the computer industry has had to completely redesign the transistors. New materials have been introduced - including the element hafnium - and new more complicated layered structures.

But Bohr acknowledges that tackling these challenges isn't delivering the same increases in processing speed we used to see. That's why, as you may have noticed, desktop computers haven't got much better in the last 10 years or so, but you can now cram the same processing power into a much smaller device, like a smartphone.

Jack Kilby's original notebook and the two first integrated circuits, manufactured from germanium

• Jack St Clair Kilby came up with the idea of the integrated circuit during the summer of 1958. According to Texas Instruments, most of his colleagues had left for the traditional two-week holiday period, but Kilby "as a new employee with no vacation, stayed to man the shop"
• Left to his own devices at work, Kilby decided to try and crack the "tyranny-of-numbers" issue facing the industry
• Kilby's first integrated circuit was about half the size of a paper clip - it's now possible to get about 100 million transistors in the same space
• The invention led Texas Instrument to win a contract to supply chips for Minuteman intercontinental ballistic missiles

Completely new technologies will be needed, he says, if chips are continue to shrink. New devices may not be based on the flow of large numbers of electrons - as they are today - but by modulating the spin of electrons, for example.

"If I think ahead 20 years from now," he says, "it's not so much how many transistors you can pack on a chip but how many transistors you can pack into a cubic volume."

Until now all microchips have been circuits etched on to a two-dimensional plane, if it becomes possible to manufacture a three-dimensional chip that would open up the possibility of far greater connectivity. The chip would function more like a human brain, Bohr says.

But he wonders whether silicon will retain its stranglehold on the world of high technology. There is a lot of research into alternative materials - compounds containing gallium, carbon, molybdenum, indium and arsenic among others. But the low costs and easy availability of silicon mean it may still be the foundation on to which these new elements are deposited.

Silicon also remains the foundation of the final of my three technological revolutions - the only one you probably haven't already guessed. This technology is already one of America's fastest-growing industries, creating tens of thousands of jobs, and it is no coincidence that, like the computer industry, it has been nurtured in Silicon Valley.

The first consumers weren't techno-nerds, however, but a bunch of cannabis-growing hippies, way up in the California hills... They were entranced by solar panels.

The man who turned them on to the sun's power was John Schaeffer, a counter-culturalist who had left San Francisco in the 70s for a hippy commune in the backwoods. Pretty soon he realised his fellow adventurers in alternative lifestyles needed somewhere to buy the shovels and lentils with which new utopias are constructed, so he opened up a general store - and one morning a guy drove up in a Porsche and asked if he was interested in a new line of business. Curious, John walked over to the car.

Blocks of silicon being prepared for the manufacture of solar panels

"He pulled out a couple of photovoltaics he'd rescued from the Space Programme," John recounts with a chuckle. "We hooked them up, and pretty soon all these hippies from the woods started filtering into the store and started going crazy about these things."

Those first solar panels were pretty modest by modern standards.

At just nine watts they would barely power even the tiniest torch and they were pricy - he sold them at $900 a pop - but his customers were rich from the profits of their pot plantations and full of tree-hugging zeal. Within a few weeks he'd sold more than 1,000 panels.

"Before long these executives from Arco Solar, the first solar company down in LA, flew up in Lear Jets in business suits to this hippy general store in Willets find out what was going on," John remembers, still laughing at the ridiculousness of it all.

But unfortunately the rest of the world was neither as wealthy nor as idealistic, and after that initial flurry of interest the development of the industry was to be a long slow slog.

The problem was the first solar panels were just too expensive.

We've already learned how Moore's Law powered an exponential increase in the number of transistors on a silicon chip. Well, another exponential law explains why the price of solar panels has fallen a hundredfold since that man in Porsche first pulled up outside John's store.

The law was first formulated by an engineer and photovoltaic pioneer called Dick Swanson, who I met in the factory down in Silicon Valley where his company Sun Power constructs solar panels.

Swanson explains that, like the computer chip, photovoltaic cells exploit the fact that pure silicon is a semiconductor.

"Silicon has the interesting property that when light hits it, it can knock loose the electrons that are bonding the atoms together," he says. Those electrons are now free to wander around.

They can go from one edge of the wafer to another, he explains. "They have no idea where they are supposed to go, so they wander aimlessly."

It's his job, as a photovoltaic cell designer, to give those electrons a sense of purpose.

"We put materials on the surface of the cell so that if an electron gets close to it, it pulls it out," he says. Every electron the sunlight knocks out leaves what he calls "a hole".

"The whole game in designing an efficient solar cell is to convince the electrons to come out one wire and the holes to come out the other," he says.

And the challenge for engineers is to do that progressively more efficiently and more cheaply.

Swanson flushes with embarrassment when I mention "Swanson's Law". He doesn't want to claim credit, but he was the first to realise just how quickly solar prices might fall.

"If you look at refrigerators, pencils or aeroplanes", he says, "they all tend to come down in cost as you make more of them, because you learn how to drive costs out and you get efficiencies as volumes increase."

Just as Moore's law forecast an exponential increase in the number of transistors on a chip, Swanson's Law predicts an exponential decrease in the price of solar. What he forecast is that every time the number of solar cells in the world doubles, the cost of making one would fall 20%.

And this law too has proved remarkably accurate. Prices have fallen like a stone since - from $100 per watt in the 70s, down to less than $1 per watt now.

That exponential fall in price is why the solar industry is beginning to really take off now. To use the jargon, solar has reached "grid parity". What that means is that in sunny places with relatively high electricity costs - like Hawaii (LINK to Vanadium), California, Japan or Italy - the cost of supplying a watt of electricity from a solar cell to the electricity grid is now very similar to the cost of generating power from coal, gas or nuclear energy.

And according to Dick Swanson there's room to cut prices still further. He thinks the price per watt could fall to 35 cents. What that means is that solar could be on the verge of delivering plentiful cheap power to much of the world, and it's very hard to understate just how important that is.

That means solar could pretty soon deliver cheap, plentiful power without- it almost goes without saying - all the consequences of the pollution of other forms of electricity generation.

Now that really would be revolutionary - and all thanks to the potential locked away in the sand of your holiday beach.

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I was raised as a Methodist and I was a believer until the age of eleven. Then I lost faith and became an annoying atheist for decades. In recent years I've come to see religion as a valid user interface to reality. The so-called "truth" of the universe is irrelevant because our tiny brains aren't equipped to understand it anyway.

Our human understanding of reality is like describing an elephant to a space alien by saying an elephant is grey. That is not nearly enough detail. And you have no way to know if the alien perceives color the same way you do. After enduring your inadequate explanation of the elephant, the alien would understand as much about elephants as humans understand about reality.

In the software world, user interfaces keep human perceptions comfortably away from the underlying reality of zeroes and ones that would be incomprehensible to most of us. And the zeroes and ones keep us away from the underlying reality of the chip architecture. And that begs a further question: What the heck is an electron and why does it do what it does? And so on. We use software, but we don't truly understand it at any deep level. We only know what the software is doing for us at the moment.

Religion is similar to software, and it doesn't matter which religion you pick. What matters is that the user interface of religious practice "works" in some sense. The same is true if you are a non-believer and your filter on life is science alone. What matters to you is that your worldview works in some consistent fashion.

If you're deciding how to fight a disease, science is probably the interface that works best. But if you're trying to feel fulfilled, connected, and important as you navigate life, religion seems to be a perfectly practical interface. But neither science nor religion require an understanding of reality at the detail level. As long as the user interface gives us what we need, all is good.

Some of you non-believers will rush in to say that religion has caused wars and other acts of horror so therefore it is not a good user interface to reality. I would counter that no one has ever objectively measured the good and the bad of religion, and it would be impossible to do so because there is no baseline with which to compare. We only have one history. Would things have gone better with less religion? That is unknowable.

If you think there might have been far fewer wars and atrocities without religion, keep in mind that some of us grow up to be Josef Stalin, Pol Pot, and Genghis Khan. There's always a reason for a war. If you add up all the people who died in holy wars, it would be a rounding error compared to casualties from wars fought for other reasons.

What I know for sure is that plenty of people around me are reporting that they find comfort and social advantages with religion. And science seems to support a correlation between believing, happiness, and health. Anecdotally, religion seems to be a good interface.

Today when I hear people debate the existence of God, it feels exactly like debating whether the software they are using is hosted on Amazon's servers or Rackspace. From a practical perspective, it probably doesn't matter to the user one way or the other. All that matters is that the user interface does what you want and expect.

There are words in nearly every language to describe believers, non-believers, and even the people who can't decide. But is there a label for people who believe human brains are not equipped to understand reality so all that matters is the consistency and usefulness of our user interface?

  _____________________________________________

Scott Adams

Co-founder of CalendarTree.com

Author of this book

P.S. Yesterday was the sixth anniversary of my surgery to fix my voice problem (spasmodic dysphonia). There was some question at the time about whether the surgery would be a permanent fix. So far, my voice has improved each year since the surgery.

I was raised as a Methodist and I was a believer until the age of eleven. Then I lost faith and became an annoying atheist for decades. In recent years I've come to see religion as a valid user interface to reality. The so-called "truth" of the universe is irrelevant because our tiny brains aren't equipped to understand it anyway.

Our human understanding of reality is like describing an elephant to a space alien by saying an elephant is grey. That is not nearly enough detail. And you have no way to know if the alien perceives color the same way you do. After enduring your inadequate explanation of the elephant, the alien would understand as much about elephants as humans understand about reality.

In the software world, user interfaces keep human perceptions comfortably away from the underlying reality of zeroes and ones that would be incomprehensible to most of us. And the zeroes and ones keep us away from the underlying reality of the chip architecture. And that begs a further question: What the heck is an electron and why does it do what it does? And so on. We use software, but we don't truly understand it at any deep level. We only know what the software is doing for us at the moment.

Religion is similar to software, and it doesn't matter which religion you pick. What matters is that the user interface of religious practice "works" in some sense. The same is true if you are a non-believer and your filter on life is science alone. What matters to you is that your worldview works in some consistent fashion.

If you're deciding how to fight a disease, science is probably the interface that works best. But if you're trying to feel fulfilled, connected, and important as you navigate life, religion seems to be a perfectly practical interface. But neither science nor religion require an understanding of reality at the detail level. As long as the user interface gives us what we need, all is good.

Some of you non-believers will rush in to say that religion has caused wars and other acts of horror so therefore it is not a good user interface to reality. I would counter that no one has ever objectively measured the good and the bad of religion, and it would be impossible to do so because there is no baseline with which to compare. We only have one history. Would things have gone better with less religion? That is unknowable.

If you think there might have been far fewer wars and atrocities without religion, keep in mind that some of us grow up to be Josef Stalin, Pol Pot, and Genghis Khan. There's always a reason for a war. If you add up all the people who died in holy wars, it would be a rounding error compared to casualties from wars fought for other reasons.

What I know for sure is that plenty of people around me are reporting that they find comfort and social advantages with religion. And science seems to support a correlation between believing, happiness, and health. Anecdotally, religion seems to be a good interface.

Today when I hear people debate the existence of God, it feels exactly like debating whether the software they are using is hosted on Amazon's servers or Rackspace. From a practical perspective, it probably doesn't matter to the user one way or the other. All that matters is that the user interface does what you want and expect.

There are words in nearly every language to describe believers, non-believers, and even the people who can't decide. But is there a label for people who believe human brains are not equipped to understand reality so all that matters is the consistency and usefulness of our user interface?

  _____________________________________________

Scott Adams

Co-founder of CalendarTree.com

Author of this book

P.S. Yesterday was the sixth anniversary of my surgery to fix my voice problem (spasmodic dysphonia). There was some question at the time about whether the surgery would be a permanent fix. So far, my voice has improved each year since the surgery.

(watch the process for this image and more on The Realist Patreon page.)

Last fall, work on my coding side projects came to a head: I wasn’t making adequate progress and I couldn’t find a way to get more done without sacrificing my ability to do effective work at Khan Academy.

There were a few major problems with how I was working on my side projects. I was primarily working on them during the weekends and sometimes in the evenings during the week. This is a strategy that does not work well for me, as it turns out. I was burdened with an incredible amount of stress to try and complete as much high quality work as possible during the weekend (and if I was unable to it felt like a failure). This was a problem as there’s no guarantee that every weekend will be free – nor that I’ll want to program all day for two days (removing any chance of relaxation or doing anything fun).

There’s also the issue that a week between working on some code is a long time, it’s very easy to forget what you were working on or what you left off on (even if you keep notes). Not to mention if you miss a weekend you end up with a two week gap as a result. That massive multi-week context switch can be deadly (I’ve had many side projects die due to attention starvation like that).

Inspired by the incredible work that Jennifer Dewalt completed last year, in which she taught herself programming by building 180 web sites in 180 days, I felt compelled to try a similar tactic: working on my side projects every single day.

I decided to set a couple rules for myself:

1. I must write code every day. I can write docs, or blog posts, or other things but it must be in addition to the code that I write.
2. It must be useful code. No tweaking indentation, no code re-formatting, and if at all possible no refactoring. (All these things are permitted, but not as the exclusive work of the day.)
3. All code must be written before midnight.
4. The code must be Open Source and up on Github.

Some of these rules were arbitrary. The code doesn’t technically need to be written before midnight of the day of but I wanted to avoid staying up too late writing sloppy code. Neither does the code have to be Open Source or up on Github. This just forced me to be more mindful of the code that I was writing (thinking about reusability and deciding to create modules earlier in the process).

Thus far I’ve been very successful, I’m nearing 20 weeks of consecutive work. I wanted to write about it as it’s completely changed how I code and has had a substantial impact upon my life and psyche.

With this in mind a number of interesting things happened as a result of this change in habit:

Minimum viable code. I was forced to write code for no less than 30 minutes a day. (It’s really hard to write meaningful code in less time, especially after remembering where you left off the day before.) Some week days I work a little bit more (usually no more than an hour) and on weekends I’m sometimes able to work a full day.

Code as habit. It’s important to note that that I don’t particularly care about the outward perception of the above Github chart. I think that’s the most important take away from this experiment: this is about a change that you’re making in your life for yourself not a change that you’re making to satisfy someone else’s perception of your work. The same goes for any form of dieting or exercise: if you don’t care about improving yourself then you’ll never actually succeed.

Battling anxiety. Prior to starting this experiment I would frequently feel a high level of anxiety over not having completed “enough” work or made “enough” progress (both of which are relatively unquantifiable as my side projects had no specific deadlines). I realized that the feeling of making progress is just as important as making actual progress. This was an eye-opener. Once I started to make consistent progress every day the anxiety started to melt away. I felt at peace with the amount of work that I was getting done and I no longer had the over-bearing desire to frantically get any work done.

Weekends. Getting work done on weekends use to be absolutely critical towards making forward momentum (as they were, typically, the only time in which I got significant side project coding done). That’s not so much the case now – and that’s a good thing. Building up a weeks-worth of expectations about what I should accomplish during the weekend only ended up leaving me disappointed. I was rarely able to complete all the work that I wanted and it forced me to reject other weekend activities that I enjoyed (eating dim sum, visiting museums, going to the park, spending time with my partner, etc.) in favor of getting more work done. I strongly feel that while side projects are really important they should not be to the exclusion of life in general.

Background processing. An interesting side effect of writing side project code every day is that your current task is frequently running in the back of your mind. Thus when I go for a walk, or take a shower, or any of the other non-brain-using activities I participate in, I’m thinking about what I’m going to be coding later and finding a good way to solve that problem. This did not happen when I was working on the code once a week, or every other week. Instead that time was consumed thinking about some other task or, usually, replaced with anxiety over not getting any side project work done.

Context switch. There’s always going to be a context switch cost when resuming work on a side project. Unfortunately it’s extremely hard to resume thinking about a project after an entire week of working on another task. Daily work has been quite helpful in this regard as the time period between work is much shorter, making it easier to remember what I was working on.

Work balance. One of the most important aspects of this change was in simply learning how to better balance work/life/side project. Knowing that I was going to have to work on the project every single day I had to get better at balancing my time. If I was scheduled to go out in the evening, and not get back until late, then I would need to work on my side project early in the day, before starting my main Khan Academy work. Additionally if I hadn’t finished my work yet, and I was out late, then I’d hurry back home to finish it up (instead of missing a day). I should note that I’ve been finding that I have less time to spend on hobbies (such as woodblock printing) but that’s a reasonable tradeoff that I’ll need to live with.

Outward perception. This has all had the added benefit of communicating this new habit externally. My partner understands that I have to finish this work every day, and thus activities sometimes have to be scheduled around it. It’s of considerable comfort to be able to say “Yes, we can go out/watch a movie/etc. but I have to get my coding in later” and have that be understood and taken into consideration.

How much code was written? I have a hard time believing how much code I’ve written over the past few months. I created a couple new web sites, re-wrote some frameworks, and created a ton of new node modules. I’ve written so much I sometimes forget the things I’ve made – work from even a few weeks prior seem like a distant memory. I’m extremely pleased with the amount of work that I’ve gotten done.

I consider this change in habit to be a massive success and hope to continue it for as long as I can. In the meantime I’ll do all that I can to recommend this tactic to others who wish to get substantial side project work done. Let me know if this technique does, or doesn’t, work for you – I’m very interested in hearing additional anecdotes!

Discuss this post on Hacker News.

Aécio Neves prometeu uma "simplificação tributária" e anunciou a meta de levar de 18% do PIB para 24% do PIB a taxa de investimento da economia (que se gaste esse tanto da renda nacional em ampliação da capacidade produtiva). Foi o que disse a empresários, em sabatina promovida pela Confederação Nacional da Indústria.

Não é razoável exigir do candidato detalhes de programas em entrevista com tantos assuntos. Mas fica a curiosidade de saber como o senador tucano trocará em miúdos suas promessas.

"Simplificação tributária" pode significar de quase nada a um excesso de ambições. A meta de levar o investimento a 24% do PIB em parte não depende do governo, em parte depende de um governo muito capaz.

Os dois assuntos estarão especialmente enredados nos próximos anos. Será também especialmente difícil lidar com tais problemas, pois o governo chegou à pindaíba, vide o resultado das contas federais do primeiro semestre, anunciado ontem: o pior desde o ano 2000.

Simplificação tributária pode significar a medicação do manicômio burocrático dos impostos. É importante, difícil, mas não custa muito além de inteligência e trabalho.

Simplificar, reduzir e esclarecer procedimentos já seria um ganho de produtividade. Mas é preciso que exista uma autoridade poderosa a cargo da tarefa, com o apoio presidencial. Os burocratas são uma montanha no meio do caminho. O governo de Dilma Rousseff fez algum progresso na redução da burocracia nos portos. Não fez mais porque, mesmo com regulamentações e normas aprovadas, a coisa empacou em burocratas e na descoordenação do governo.

Simplificação tributária pode significar também algo como reforma tributária. Trata-se de tarefa politicamente muito mais complicada (envolve Estados e municípios) e que exige algum dinheiro no caixa do governo, o que não haverá nos próximos dois anos.

Uma reforma tributária mesmo mínima, no presente caso do Brasil, exige que o governo federal compense Estados e municípios (banque perdas de receita devida à racionalização dos tributos). Pode implicar perda direta de receita federal, pois é difícil calcular, a princípio, o efeito de impostos novos.

Repita-se: não haverá dinheiro, pois o Brasil crescerá pouco em 2015 e talvez em 2016. Não haverá dinheiro, de resto, porque o governo tem de aumentar sua poupança, de modo a colocar a economia nos trilhos elementares (isto é, tem de poupar mais a fim de ajudar a controlar a inflação, baixar juros etc).

Aliás, medida razoável e talvez inevitável do próximo governo será aumentar algum imposto de modo a fechar as contas com sobra bastante para evitar o aumento da dívida pública.
A perspectiva de inflação e juros mais baixos (custos menores e estabilidade) é uma condição mínima para a retomada da confiança empresarial e dos investimentos.

Em suma, não haverá condição de reforma tributária mínima ou de aumento da taxa de investimentos sem um plano imediato que coloque ordem nas contas públicas e que crie a expectativa de baixa gradual da inflação e juros. Sem passar por essa primeira barreira, a coisa desanda.

Weekly protest in Bil'in, June 2011 (Anna Paq, courtesy of ActiveStills.org)

Writing on July 19 in a column intended to “correct a few common misconceptions” about the Israeli-Palestinian conflict, Nicholas Kristof perpetuated one of his own. Offering unsolicited advice to Palestinian political leaders, Mr. Kristof wrote: “If Palestinians turned to huge Gandhi-style nonviolence resistance campaigns [sic], videos would reverberate around the world and Palestine would achieve statehood and freedom.” Mr. Kristof’s sentiment is admirable. His glaring ignorance of ongoing Palestinian peaceful grassroots campaigns is not.

At a time of colossal regional violence, the growth of peaceful grassroots campaigns for Palestinian statehood and civil rights is one of the few uplifting stories in Israeli-Palestinian politics. Over the past decade, these campaigns have originated in communities with particular grievances, and slowly transformed into weekly marches for civil rights and statehood. In Bil’in, Palestinians have marched every Friday since February 2005, when community members first organized in defiance of the expropriation of half of the village’s farmland by the neighboring Modiin Illit settlement (the Israeli High Court returned one-half of the stolen land in 2007). Those demonstrations were featured in the Academy Award–nominated documentary 5 Broken Cameras, one of the few instances of global media attention on Palestinian peaceful protests. In Nabi Saleh, weekly marches have protested a similar expropriation of land, and the denial of basic civil rights by military rule. Other active villages include Budrus, Jayyous, Beit Surik, Biddo, Al-Wlajeh, Ni’lin, Ma’sara, Beit Ummar, and Iraq Burin, among others. Weekly demonstrations include anywhere from several dozen to several hundred protesters.

Weekly marches have not been the only Palestinian peaceful campaigns. Other methods include barricading roads on which Palestinians are not permitted to drive, mass prayer events, and hunger strikes. The Popular Struggle Coordination Committee serves as an umbrella organization for these efforts, coordinating “marches, strikes, demonstrations, direct actions and legal campaigns, as well as supporting boycott, divestment and sanctions,” according to its website. Some peaceful protesters have also worked with American and European counterparts to organize international demonstrators, such as a series of demonstrations on April 15, 2014, to protest use of U.S. tax funds to support the Israeli occupation.

The leaders who have emerged from these movements speak the Gandhian language of transformative nonviolence that Mr. Kristof implores them to employ. When I was in Bil’in last month, leading activist Iyad Burnat explained his philosophy of nonviolence to me: “I want my freedom, and I am not free if I harm another person.” Another activist in Bil’in, who preferred not to be named for fear of reprisal, told me: “If you want to visit my home, I do not care if you are Muslim, Jewish, or Christian. But you cannot bring violence with you, you cannot solve disputes with violence. That is our message to the Israelis who occupy us.”

While Mr. Kristof is wrong that Palestinians have yet to learn the value of peaceful grassroots campaigns, he is right that the Gandhi-like Palestinian movement is not “huge.” Why haven’t more Palestinians joined the movement? One theory is that Palestinians refuse to reject militancy. Another is that they fear the draconian violence visited upon peaceful protesters by the Israel Defense Force.

To understand why more Palestinians haven’t joined weekly peaceful protests, it’s important to consider something that Mr. Kristof likely overlooked in formulating his advice: Israeli Military Executive Order 101 outlaws political gatherings of more than ten Palestinians in the West Bank, meaning that Palestinian peaceful gatherings inherently amount to illegal civil disobedience. Unsurprisingly, the Israel Defense Forces responds to these protests with force as a matter of policy. Nearly every Friday in the Palestinian villages in which demonstrations occur, the IDF unleashes an occasionally lethal, always perilous, combination of tear gas, rubber-coated bullets, water cannon–fired “skunk” liquid, and—sometimes—live fire. One study found that between 2004 and 2011, thirteen Palestinian civilians were killed in nonviolent demonstrations; Iyad Burnat, the Bil’in organizer, puts the overall figure at closer to forty.

The IDF also punishes villages known for nonviolent civil disobedience campaigns in other ways. Nonviolent demonstrators have been arrested and imprisoned for “incitement”; children can be detained and processed in the IDF’s notoriously gruesome military court system, whose treatment of children UNICEF has called “cruel, inhumane and degrading”; and permits for work in Israel can be revoked. The IDF has confirmed that it uses collective punishment against villages in which these protests occur. It turns out that there are substantial costs to even peaceful resistance against the state that controls your access to water, electricity, transportation, employment, and freedom of mobility. In this context, what seems remarkable is not that more Palestinians do not join the demonstrations, but that so many have persevered over the past decade.

These harsh IDF responses are not provoked by Palestinian violence. A leaked 2010 U.S. State Department memo records Israel’s top military official in the West Bank, General Avi Mizrahi, promising to use skunk water and mass arrests to quell “even demonstrations that appear peaceful.” As one senior Israeli military official told an American counterpart in 2011: “We don’t do Gandhi very well.”

While Israel’s response to Gandhi-style tactics has been utterly condemnable, Palestinians have certainly not perfected the tactic. Kristof writes that “too many Palestinians define nonviolence to include rockthrowing. No, that doesn’t cut it.” Mr. Kristof is right that occasional rock-throwing does occur, but he is thoroughly wrong to define and dismiss the movement by this practice. Stone-throwing is not employed as an organized strategy of demonstrators, who use marches and sit-ins to make their point; those who throw stones tend to act alone or in small groups, and often after the IDF initiates violence against peaceful demonstrators.

The relentless emphasis on stone-throwing cedes any sense of proportionality, ignoring the egregious violence with which the IDF crushes Palestinian demonstrations by official policy. As Iyad Tamimi, a leading organizer in Nabi Saleh, told me when I visited the village last month: “After one day of protest, we pick up 1,500 tear gas canisters. Are the Israelis nonviolent?”

To substantiate his claim about rock-throwing, Mr. Kristof turns not to a third-party report, but instead links to the official IDF blog. On that page, the IDF misleadingly boasts of “protecting the right of Palestinians to protest peacefully,” despite the fact that Israeli military law explicitly denies Palestinians the right to political demonstration.

Of course, it would be ideal for no rock-throwing to occur, just as it would be ideal for the IDF not to resort to violence in crushing popular demonstrations, just as it would be ideal, writ large, for the IDF to withdraw from the West Bank, which it occupies in contravention of international law. But demanding that Palestinians absorb the tremendous personal costs of nonviolent civil disobedience, then dismissing the promising movement because of marginal stone-throwing, all while ignoring the vast IDF violence against Palestinian civilians—this is not the empathy Mr. Kristof has offered to others struggling for human rights around the globe.

This brazen disproportionality is precisely why Mr. Kristof’s advice is so insulting. In the past decade, Palestinians living under a grinding military occupation have undertaken profound personal and community sacrifices to organize peaceful demonstrations for civil rights and statehood. Instead of empowering these courageous moderates by sharing their stories, Mr. Kristof turns a blind eye, dismissing the cost of their courage while arrogantly suggesting that he will pay attention when Palestinians learn to behave perfectly.

It’s this type of superficial media coverage that makes so preposterous Mr. Kristof’s prediction that “the resulting videos [of nonviolence resistance campaigns] would reverberate around the world and Palestine would achieve statehood and freedom.” The videos are here, here, here, and here, among other places, Mr. Kristof. Will you start sharing them?

Sam Sussman co-directs Extend, an American start-up non-profit organization that offers five-day educational tours of the West Bank to young American Jews. He is an M.Phil. candidate in International Relations at Oxford. He tweets @SamSussman1.

Algebraic data types are the fundamental building blocks of programs in ML-style languages like Haskell and OCaml. Since they play such an important role in these languages, it is well worth understanding how they work and where they come from—at first, the design may feel a bit arbitrary, but in reality it flows naturally from a reasonable starting point.

Algebraic data types are made up of two components: products (also known as structs, records or tuples) and variants (also known as tagged unions, sums or coproducts). Let’s take a look at each of these in turn, how they can be combined and how they’re related.

Products

Products are a construct that appears in most programming languages: it’s a type that contains multiple values. The simplest example in OCaml would be a pair (just like an ordered pair in mathematics):

# let pair = (1, 2);;
val pair : int * int = (1, 2)

This pair has the type int * int which means it has two members, both integers. In prose rather than code, this is often written as int × int because it corresponds to a cross-product of sets. Fundamentally, we can do two interesting things with a pair: get the first element or get the second element:

# let first (x, y) = x;;
val first : 'a * 'b -> 'a = <fun>
# let second (x, y) = y;;
val second : 'a * 'b -> 'b = <fun>

In OCaml, pattern matching makes the definitions pretty visual. The functions first and second are often abbreviated as fst and snd or π₁ and π₂ (π is used because these are projection functions).

Of course, we want to be able to build up more complicated types than pairs, so most languages support having any number of fields

let tuple = (1, 2, 3, 4);;
val tuple : int * int * int * int = (1, 2, 3, 4)

and giving fields names

# type blarg = { foo : int; bar : int };;
type blarg = { foo : int; bar : int; }
# let x = { foo = 1; bar = 2 };;
val x : blarg = {foo = 1; bar = 2}

This is very useful for actual programming, but does not really give us any new capabilities. Both larger tuples and records are isomorphic to constructions made up of just pairs; for example, we can go back and forth between int * int * int * int and int * (int * (int * int)) (made up of nested pairs):

let from (a, b, c, d) = (a, (b, (c, d)));;
let to' (a, (b, (c, d))) = (a, b, c, d);;

This is good news: it means that to understand products in their full generality, we just need to understand pairs. Other constructs like larger tuples and records come “for free” because we can always build up an equivalent structure just out of pairs.

You’ll note that records are very similar to features of languages like C that don’t have tuples at all—records are just like C structs! Even in Java, a language pretty far removed from OCaml, we have record-like functionality in the form of fields on objects; a value object is pretty much the same as an OCaml record:

public class Blarg {
  public final int foo, bar
}

So products are certainly a pretty universal construct. While these languages do not have tuples or pairs themselves, we can still think about their products in terms of tuples, which will let us reuse our theory of product types in a lot of different contexts.

Variants

The other component of algebraic data types are variants. Unlike products, variants only tend to exist directly in functional languages—most common OO and procedural languages do not support them directly, although certain common patterns try to emulate them. Happily, it looks like this is changing with the advent of languages like Rust and Swift which do support them.

Where products contain multiple values, variants can be any of multiple possibilities. Instead of having both field 1 and field 2, they have either field 1 or field 2. In fact, that’s what we can call our simple variant building block: either (in the spirit of Haskell):

type ('a, 'b) either = Left of 'a 
                     | Right of 'b

We can construct different values of this type:

# let left = Left 1;;
val left : (int, 'a) either = Left 1
# let right = Right 1;;
val right : ('a, int) either = Right 1

In real programming, we generally write custom variants for our types:

type AST = Expr of ...
         | Stmt of ...
         | Comment of ...

However, just like for products, these more complicated types are ultimately isomorphic to some nested series of eithers.

In a lot of ways, variants are like an extension of enumeration types (enums) in other languages. Enums in languages like Java also have a series of tags, those tags just can’t have any values attached to them. Here’s an example:

public enum State {
  Running, Paused, Stopped
}

This could be written with a variant by having constructors that do not carry any values:

type state = Running
           | Paused
           | Stopped

These sorts of types are pretty useful, but not nearly as versatile as full variants. For example, consider the option type which lets us make values nullable:

type 'a option = Some of 'a
               | None

This is only possible because a variant’s constructor can carry a value. It’s a very useful type in practice because it lets normal values in OCaml not be nullable. As a quick reference, we could express this in terms of our either type by making one of the branches hold unit:

type 'a option = ('a, unit) either
Left value
Right ()

Here, Right () plays the role of the constructor None. Whenever we see a constructor with no arguments, we can always express it as a branch of an either with unit.

To actually get data out of a tagged union, we have to pattern match on it providing a case for each possible constructor:

match my_either with
  | Left a  -> ...
  | Right b -> ...

Making Sense of Variants

Products are an entirely natural programming construct: putting multiple values together is something that emerges very naturally from any non-trivial program we may want to write. On the other hand, variants feel a bit more arbitrary: why the tags? Why not just a union type? I think this is part of the reason why variants are uncommon in more popular languages.

Compared to type unions, variants are generally safer: we always know what we put in at runtime. In fact, quite often, C unions are used to emulate variants with an explicit tag (hence the name “tagged union”):

enum Tag { Left; Right }

struct Either {
  enum Tag tag;
  union {
    int left;
    char* right;
  }
}

The idea is to check the tag each time you read the value, to make sure you’re getting the right sort of data from the union. Ultimately, this reasonably common pattern amounts to jury-rigging variants on top of enums and unions, without language support which makes it easier to make mistakes.

In object-oriented programming, the visitor design pattern serves a similar role. The visitor pattern uses OO mechanisms to emulate pattern matching in the OO language, letting us write variant-like code.

Already, we can see that variants aren’t completely arbitrary: one way or another, they tend to emerge as a coding pattern of some sort. At the same time, the fact that they emerge indirectly and often unacknowledged means that it’s a less intuitive concept than a product.

Another way of looking at how products and variants fit together is in terms of the “shape” of a product. What do I mean by that? Let’s start by drawing some diagrams about the types involved. Given a pair A × B, we have the two projection operations from it:

But what makes A × B particularly special compared to any other type C that also happens to have functions to A and B?

The core difference is that, in some sense, the product doesn’t carry any additional information beyond that of its fields. The only important things you can do with it are get the first value or get the second value out. This is not necessarily true of some other type C, even if it does let you get an A or a B out.

We can state this more formally as follows: for any type C with functions f : C → A and g : C → B, there is exactly one function t : C → A × B such that π₁ (t c) = f c and π₂ (t c) = g c for every value c of type C. In other words, either of the possible paths from C to A or B are equivalent (t is the function denoted by a dotted line):

This might seem a bit weird, until you look at how we can define t in general:

let t c = (f c, g c)

So really, this whole thing is a fancy way of saying that we can apply both functions and put them into a tuple!

But why is this interesting? Well, it turns out that we can draw a very similar diagram from a variant A + B. The only difference is that the arrows are flipped! Otherwise, the same sort of relationships hold.

So, in an abstract way, both products and variants have the same core structure, with a particular kind of symmetry between them. Technically speaking, they are duals of each other. To me, this symmetry is strong evidence that variants really make sense: they’re just a natural extension of products, which are entirely natural themselves.

This duality also makes certain other properties and behaviors of algebraic data types emerge. Many languages have subtyping for records (or record-like things—classes). The idea is simple: if we need something with two fields a and b, we can always substitute in a bigger record and just ignore the extra fields.

But how do we do subtyping with variants? Well, just like we flipped the arrows in the diagrams, we flip the requirement: we can always substitute in a smaller variant. In some sense, we get this relationship for free just by acknowledging the duality of products and variants. This is particularly relevant for OCaml because, unlike most other languages, it actually supports this sort of subtyping directly in the form of polymorphic variants.

Putting it all together

Products and variants together—with some nice syntax—give us algebraic data types, which form a surprisingly expressive basis for modeling different domains. We can write types that have multiple constructors, each having multiple arguments:

type foo = Foo of string * int
         | Bar of bool * float
         | Baz of int list

Below the fancy syntax, this is still isomorphic to a bunch of nested pairs and eithers. Reimplementing foo in these terms is a great exercise to really understand this relationship.

One of the most direct ways in which algebraic data types like this are useful is for working with abstract syntax trees. For example, here’s an AST for the simply typed λ-calculus with basic arithmetic:

We could represent it almost directly as an algebraic data type:

type expr = Unit
          | Integer of int
          | Plus of expr * expr
          | Variable of name
          | Lambda of name * type * expr
          | App of expr * expr

This makes for a definition that is fairly easy to follow, largely because it reflects the “shape” of the domain (the grammar) well. This becomes even more useful when you go to write an interpreter for this language: the eval function also follows the shape of the algebraic data type, guiding your implementation.

Another example in a similar vein is using an algebraic data type to represent JSON:

type json = Object of json StringMap
          | Array of json list
          | String of string
          | Number of float
          | True
          | False
          | Null

Apart from being a concise definition that captures all of JSON, this also makes traversing JSON values easy by pattern matching.

Ultimately, algebraic data types are just combinations of products and variants, which turn out to be symmetric concepts. There really isn’t much of a case for not including variants in your language when you already have product types, whether they are tuples or structs or records or even classes. They just fit too well together. And, from a practical standpoint, the combination of the two is an expressive way to declare the data types you’re working with.

For billions of years, single-celled creatures had the planet to themselves, floating through the oceans in solitary bliss. Some microorganisms attempted multicellular arrangements, forming small sheets or filaments of cells. But these ventures hit dead ends. The single cell ruled the earth.

Then, more than 3 billion years after the appearance of microbes, life got more complicated. Cells organized themselves into new three-dimensional structures. They began to divide up the labor of life, so that some tissues were in charge of moving around, while others managed eating and digesting. They developed new ways for cells to communicate and share resources. These complex multicellular creatures were the first animals, and they were a major success. Soon afterward, roughly 540 million years ago, animal life erupted, diversifying into a kaleidoscope of forms in what’s known as the Cambrian explosion. Prototypes for every animal body plan rapidly emerged, from sea snails to starfish, from insects to crustaceans. Every animal that has lived since then has been a variation on one of the themes that emerged during this time.

How did life make this spectacular leap from unicellular simplicity to multicellular complexity? Nicole King has been fascinated by this question since she began her career in biology. Fossils don’t offer a clear answer: Molecular data indicate that the “Urmetazoan,” the ancestor of all animals, first emerged somewhere between 600 and 800 million years ago, but the first unambiguous fossils of animal bodies don’t show up until 580 million years ago. So King turned to choanoflagellates, microscopic aquatic creatures whose body type and genes place them right next to the base of the animal family tree. “Choanoflagellates are to my mind clearly the organism to look at if you’re looking at animal origins,” King said. In these organisms, which can live either as single cells or as multicellular colonies, she has found much of the molecular toolkit necessary to launch animal life. And to her surprise, she found that bacteria may have played a crucial role in ushering in this new era.

In a lengthy paper that will be published in a special volume of Cold Spring Harbor Perspectives in Biology in September, King lays out the case for the influence of bacteria on the development of animal life. For starters, bacteria fed our ancient ancestors, and this likely required those proto-animals to develop systems to recognize the best bacterial prey, and to capture and engulf them. All of these mechanisms were repurposed to suit the multicellular lives of the first animals. King’s review joins a broad wave of research that puts bacteria at the center of the story of animal life. “We were obliged to interact intimately with bacteria 600 million years ago,” said King, now an evolutionary biologist at the University of California, Berkeley, and an investigator with the Howard Hughes Medical Institute. “They were here first, they’re abundant, they’re dominant. In retrospect we should’ve expected this.”

Multicellular Motivation

Although we tend to take the rise of animals for granted, it is reasonable to ask why they ever emerged at all, given the billions of years of success of unicellular organisms. “For the last 3.5 billion years, bacteria have been around and abundant,” said Michael Hadfield, a professor of biology at the University of Hawaii, Manoa. “Animals never showed up until 700 or 800 million years ago.”

The technical demands of multicellularity are significant. Cells that commit to living together need a whole new set of tools. They have to come up with ways of sticking together, communicating, and sharing oxygen and food. They also need a master developmental program, a way to direct specific cells to take on specialized jobs in different parts of the body.

Nonetheless, during the course of evolution, the transition to multicellularity happened separately as many as 20 different times in lineages from algae to plants to fungi. But animals were the first to develop complex bodies, emerging as the most dramatic example of early multicellular success.

To understand why this might have happened the way it did, King began studying choanoflagellates, the closest living relative to animals, nearly 15 years ago as a postdoc at the University of Wisconsin, Madison. Choanoflagellates are not the most charismatic of creatures, consisting of an oval blob equipped with a single taillike flagellum that propels the organism through the water and also allows it to eat. The tail, thrashing back and forth, drives a current across a rigid, collarlike fringe of thin strands of cell membrane. Bacteria get caught up in the current and stick to the collar, and the choano engulfs them.

What intrigued King about choanoflagellates was their lifestyle flexibility. While many live as single cells, some can also form small multicellular colonies. In the species Salpingoeca rosetta, which lives in coastal estuaries, the cell prepares to divide but stops short of splitting apart, leaving two daughter cells connected by a thin filament. The process repeats, creating rosettes or spheres containing as many as 50 cells in the lab. If this all sounds familiar, there’s a reason for it — animal embryos develop from zygotes in much the same way, and spherical choanoflagellate colonies look uncannily like early-stage animal embryos.

When King began studying S. rosetta, she couldn’t get the cells to consistently form colonies in the lab. But in 2006, a student stumbled on a solution. In preparation for genome sequencing, he doused a culture with antibiotics, and it suddenly bloomed into copious rosettes. When bacteria that had been collected along with the original specimen were added back into a lab culture of single choanoflagellates, they too formed colonies. The likely explanation for this phenomenon is that the student’s antibiotic treatment inadvertently killed off one species of bacteria, allowing another that competes with it to rebound. The trigger for colony formation was a compound produced by a previously unknown species of Algoriphagus bacteria that S. rosetta eats.

S. rosetta seems to interpret the compound as an indication that conditions are favorable for group living. King hypothesizes that something similar could have happened more than 600 million years ago, when the last common ancestor of all animals started its fateful journey toward multicellularity. “My suspicion is that the progenitors of animals were able to become multicellular, but could switch back and forth based on environmental conditions,” King said. Later, multicellularity became fixed in the genes as a developmental program.

King’s persistence in studying this humble organism, which was overlooked by most contemporary biologists, has won her the admiration of many of her fellow scientists (as well as a prestigious MacArthur fellowship). “She strategically picked an organism to gain insight into early animal evolution and systematically studied it,” said Dianne Newman, a biologist at the California Institute of Technology in Pasadena, who studies how bacteria coevolve with their environment. King’s research offers a thrilling glimpse into the past, a rare window into what might have been going on during that mysterious period before the first fossilized animals appeared. The research is a “beautiful example” of how bacteria shape even the simplest forms of complex life, Newman said. “It reminds us that even at that level of animal development, you can expect triggers from the microbial world.” The bacteria system in S. rosetta can now be used to answer more specific questions, such as what the benefit of multicellularity might be — a question King and her collaborators at Berkeley are now working to answer.

Of course, just because bacteria trigger modern choanoflagellates into group living, that doesn’t mean they had the same effect on the first proto-animals. King’s finding is “really cool,” said William Ratcliff, a biologist at the Georgia Institute of Technology in Atlanta who experimentally induces yeast to form multicellular colonies. “I think she’s doing some of the most interesting research in the origins of animals.” But, he cautions, it’s possible that choanoflagellates evolved this mechanism long after they diverged from the creatures that became the first ancestors of animals. “We don’t have a clear picture of when the bacterial response evolved,” he explained. “It’s hard to know if something happened before the split between choanoflagellates and animals, or after.”

“I think there is enough evidence to allow us to hypothesize that bacteria were an important influence on animal origins — they were abundant, diverse, and they exert important signaling influences on diverse animal lineages as well as on non-animals,” King said. “But I think it is premature to say what the nature of that influence was.”

One strong hint that bacteria may have prompted that ancient transition to multicellularity is that many of today’s simplest animals are governed by microbial messages. Corals, sea squirts, sponges and tube worms all begin life as larvae floating in the water, and other research teams have shown that they too respond to compounds released by bacteria as signals to attach themselves to rocks or other surfaces and transition to a new life form. If this kind of relationship is so common among animals from the most ancient families, it seems plausible that the first animals were equally attuned to their bacterial neighbors. Figuring out how, exactly, the bacteria trigger this response will help clarify whether they played a similar role long ago. “It was a radical thought to me when we first started studying it, and now I don’t know why it’s a surprise,” King said. “The more I think about host-microbe interactions, the less surprised I become.”

The biology of choanoflagellates resembles that of animals in other unexpected ways, King found. In 2008 she led the team that published the genome of Monosiga brevicollis, a choanoflagellate that doesn’t form colonies. The sequence revealed genes for dozens of sections of proteins that also appear in multicellular animals, where they help cells stick together and also guide development and differentiation. What are they doing in single cells? King’s work suggests they arose in single-celled organisms to monitor environmental conditions and recognize other cells such as bacterial prey. In multicellular animals, the gene domains found new purposes, such as allowing cells to signal one another. Single cells used these tools to listen in on the environment. Later on, the first cells to adopt a multicellular lifestyle probably repurposed the same systems to pay attention to their sister cells, King suggested.

What Took Animals So Long?

What triggered the explosion of complex multicellular life in the Cambrian period? Increased oxygen undoubtedly had something to do with it — prior to a period sometime before 800 million years ago, atmospheric oxygen levels were too low to diffuse easily into organisms with multiple layers of cells, limiting the size of all life forms. But an increase in oxygen is probably not the whole story, said Andrew Knoll, a professor of earth and planetary sciences at Harvard University. Once oxygen levels rose past this low level, predation likely provided a strong incentive for animals to get bigger and more complicated, and to develop new body plans. It was an ecological arms race of size and complexity: Bigger predators have an advantage in catching prey, while larger prey can more easily avoid being eaten. The need to escape or repel predators also likely inspired the first scales, spines and body armor, as well as some of the wilder body plans seen in Cambrian fossils.

King’s discovery about choanoflagellates is just one of the latest insights into the intimate relationships between bacteria and animals (or, in this case, animal-like organisms). Historically, photosynthetic bacteria pumped oxygen into the oceans for billions of years, setting the stage for complex multicellular life. And according to the endosymbiotic theory, proposed in the 20th century and now widely accepted, the mitochondria inside every eukaryotic cell were once free-living bacteria. At some point more than a billion years ago, they took up residence inside other cells in a symbiotic relationship that endures in nearly every animal cell to this day. In their role as dinner, bacteria also likely provided raw genetic material for the first animals, which probably incorporated chunks of microbial DNA directly into their own genomes as they digested their meals.

But the full story of the microbial-animal relationship is even broader and deeper, argues Margaret McFall-Ngai, a biologist at the University of Wisconsin, Madison, and it’s a story that is only beginning to be told. In her view, animals should rightly be considered host-microbe ecosystems. Several years ago McFall-Ngai, along with Hadfield, convened a broad group of developmental biologists, ecologists, environmental biologists and physiologists, including King, and asked them to formulate a microbial manifesto — a declaration of bacterial significance. The paper, which appeared late last year in the Proceedings of the National Academy of Sciences, cites evidence from many corners of biology to argue that the influence of microbes on the origin, evolution and function of animals is pervasive and essential to understanding how animal life evolved. “They evolved in a world saturated with bacteria,” Hadfield said.

The breadth and significance of the animal-bacteria relationship goes far beyond the development of a handful of ancient aquatic creatures like sponges. McFall-Ngai’s own research shows that bacteria are necessary for the development of organs in squid; others have found similar partnerships that shape the maturation of animal immune systems, the guts of zebra fish and mice, and even mammalian brains. Likewise, bacteria are essential partners in the digestive systems of creatures ranging from termites to humans. The influence of microbes is even inscribed on our genome: More than a third of human genes have their origins in bacteria. These and other new findings will soon fundamentally alter our understanding of life, McFall-Ngai predicts: “Biology is in a revolution.”

So in the end, maybe animals really aren’t all that special. After all, they’d be nothing without their microbial friends. And as King’s research has revealed, much of what animals do that seems to make them interesting can also be accomplished by choanoflagellates. To her, that doesn’t diminish either one. “I love choanoflagellates,” she said. “They’re so fascinating. I see that they’re doing a lot of the same things as animals, and I can see parallels between their biology and the cell biology of animals. I could watch them for hours.”

Corrected on July 29, 2014: An earlier version of this article incorrectly stated that “Animals never showed up until 700,000 or 800,000 years ago.” The correct figure is 700 to 800 million years ago.

This article was reprinted on Wired.com.

Amanhã, 01/08, os coordenadores dos candidatos a Presidente da República participam de um debate sobre o sistema de segurança e o sistema prisional no 8º Encontro do Fórum Nacional de Segurança Pública, na Fundação Getúlio Vargas, em São Paulo. Será uma excelente oportunidade para vermos o compromisso das candidaturas à presidência com a agenda da segurança. Será que na próxima gestão eles terão coragem política para segurar o rojão?

Desde os anos 1960, quando os roubos e a violência começaram a assustar os moradores das grandes cidades brasileiras, não houve um único presidente disposto a encarar a situação de frente. Na fase mais recente de nossa democracia, Fernando Henrique, Lula e Dilma preferiram fechar os olhos para o tema, deixando que a bomba estourasse no colo dos governadores. Em comum, os três ex-presidentes ingressaram na política fazendo oposição à Ditadura Militar e às forças de segurança do regime. Lidavam com o tema pela negação, contribuindo para que as taxas crescentes de crime passassem a assombrar todo o Brasil.

A sensação geral de impunidade parece produzir homens e mulheres com raiva, que defendem a justiça feitas pelas próprias mãos.

A próxima eleição presidencial pode mudar esse quadro, num momento delicado. É o que saberemos no debate. O primeiro motivo, dos sete, é que mesmo tendo se tornado o terceiro país com maior população carcerária no mundo, as taxas de crime não param de crescer. Os homicídios aceleraram em estados do Norte e Nordeste. Os roubos aumentam mês a mês em São Paulo, estado onde a violência policial já persiste há quase quatro décadas. O tráfico de drogas se espalhou com força por quase todos os estados. A sensação geral de impunidade parece produzir homens e mulheres com raiva, que defendem a justiça feitas pelas próprias mãos.

Os dois candidatos da oposição, Aécio Neves (PSDB) e Eduardo Campos (PSB), perceberam a relevância do tema e levaram a pauta no debate presidencial. É a forma dos dois tentarem se diferenciar da presidente Dilma, que também vem ensaiando uma postura mais ativa da presidência na área da segurança.

Existe um bom motivo para os presidentes cruzarem os braços. Para justificar a omissão, os marqueteiros já perceberam que a segurança pública traz apenas ônus político e nenhum bônus ao presidente. Deixando a bucha para os governadores, eles podem se mexer apenas em situação de crise, como salvadores da pátria, depois dos governadores pedirem socorro. Foi o que ocorreu no Espírito Santo, Rio de Janeiro, Santa Catarina, para citar alguns casos.

Trata-se de um argumento eleitoral, que eu já tento derrubar de cara para empatar o jogo. A democracia brasileira vai se fortalecer quando as decisões forem tomadas em cima de valores políticos, e não em decorrência dos valores do mercado eleitoral. Não ouça os marqueteiros, a pior figura surgida na política nacional. Candidatos: mandem-os vender sabão. É para isso que eles servem.

 Outras 6 possibilidades de ação

Só que há outras razões. Abaixo, seguem outras seis importantes possibilidades de ação, discutidas por especialistas em segurança pública, num encontro organizado pelo Instituto Sou da Paz. Esses pontos formam uma agenda de segurança a ser apresentada aos candidatos com o objetivo de obter compromissos com as propostas. Tive o privilégio de participar do debate, ouvindo muito mais do que propondo. São elas:

1) A primeira trata do estabelecimento de um novo pacto federativo. A Constituição de 1988 engessou a gestão da segurança nos estados, definindo competências para as polícias, responsabilidades pelos recursos etc. O arranjo vêm se comprovando um desastre para lidar com o crime. Seria necessário a redefinição das competências e os mecanismos de governança e de financiamento para União, Estados e Municípios. A mudança exige uma emenda constitucional e a liderança do presidente para iniciar a mobilização.

2) Melhorar a produção e a difusão das informações que são matérias-primas para formulação de políticas públicas. São dados consistentes que permitem diagnosticar o problema de forma realista. Diversos estados ainda produzem dados de péssima qualidade, o que impede a qualidade da ação.

3) Criar uma política para a redução de homicídios no país. Recolher armas de fogo, equipar as divisões de homicídio, identificar a dinâmica dos conflitos, atuar de forma focada com políticas de controle e prevenção nos territórios mais violentos. Também é importante reduzir a letalidade policial, que em São Paulo chega a matar perto de 20% do total de vítimas de homicídio.

4) Rediscutir com urgência o modelo de polícia brasileiro. Há um consenso sobre a necessidade de criar polícias de ciclo completo, que façam o trabalho ostensivo e investigativo. A mudança demanda uma emenda na Constituição. Controle externo forte e autônomo, além da alteração de aspectos da natureza militar das polícias, como a extinção da Justiça Militar e a retirada do caráter de força auxiliar do Exército são outras reformas consideradas importantes.

5) Modernizar a política criminal e penitenciária. A ideia é racionalizá-la, prendendo quem comete os crimes mais graves e priorizando alternativas penais para responsabilizar os que comentem crimes mais leves. Também é importante auxiliar os estados a retomar o controle sobre as prisões.

6) Oferecer alternativas à atual política de drogas. São os acusados por tráfico de drogas aqueles que vêm superlotando as prisões. Nos presídios são formados verdadeiros escritórios de droga, de onde são comandados os mercados em diversos estados brasileiros. Os especialistas sugerem a revisão de aspectos da lei de drogas para reduzir o encarceramento de pequenos traficantes.

Placar final: 7 x 1. Há sete razões para o presidente assumir um problema. E um motivo bem sem-vergonha para não entrar.

Participaram da criação da agenda:

Instituto Sou da Paz, Ilona Szabo, Renato Sérgio de Lima, Luiz Flávio Sapori, Haydée Caruso, Claudio Beato, Rodrigo Ghiringhelli, José Luiz Ratton, Eduardo Pazinato, Ignácio Cano e Bruno Paes Manso

Can you imagine how awesome it would have been to be an entrepreneur in 1985 when almost any dot com name you wanted was available? All words; short ones, cool ones. All you had to do was ask. It didn’t even cost anything to claim. This grand opportunity was true for years. In 1994 a Wired writer noticed that mcdonalds.com was still unclaimed, so with our encouragement he registered it, and then tried to give it to McDonalds, but their cluelessness about the internet was so hilarious it became a Wired story. Shortly before that I noticed that abc.com was not claimed so when I gave a consulting presentation to the top-floor ABC executives about the future of digital I told them that they should get their smartest geek down in the basement to register their own domain name. They didn’t.

The internet was a wide open frontier then. It was easy to be the first in category X. Consumers had few expectations, and the barriers were extremely low. Start a search engine! An online store! Serve up amateur videos! Of course, that was then. Looking back now it seems as if waves of settlers have since bulldozed and developed every possible venue, leaving only the most difficult and gnarly specks for today’s newcomers. Thirty years later the internet feels saturated, bloated, overstuffed with apps, platforms, devices, and more than enough content to demand our attention for the next million years. Even if you could manage to squeeze in another tiny innovation, who would notice it?

Yet if we consider what we have gained online in the last 30 years, this abundance smells almost miraculous. We got: Instant connection with our friends and family anywhere, a customizable stream of news whenever we want it, zoomable 3D maps of most cities of the world, an encyclopedia we can query with spoken words, movies we can watch on a flat slab in our pocket, a virtual everything store that will deliver next day — to name only six out of thousands that could be mentioned.

But, but…here is the thing. In terms of the internet, nothing has happened yet. The internet is still at the beginning of its beginning. If we could climb into a time machine and journey 30 years into the future, and from that vantage look back to today, we’d realize that most of the greatest products running the lives of citizens in 2044 were not invented until after 2014. People in the future will look at their holodecks, and wearable virtual reality contact lenses, and downloadable avatars, and AI interfaces, and say, oh, you didn’t really have the internet (or whatever they’ll call it) back then.

And they’d be right. Because from our perspective now, the greatest online things of the first half of this century are all before us. All these miraculous inventions are waiting for that crazy, no-one-told-me-it-was-impossible visionary to start grabbing the low-hanging fruit — the equivalent of the dot com names of 1984.

Because here is the other thing the greybeards in 2044 will tell you: Can you imagine how awesome it would have been to be an entrepreneur in 2014? It was a wide-open frontier! You could pick almost any category X and add some AI to it, put it on the cloud. Few devices had more than one or two sensors in them, unlike the hundreds now. Expectations and barriers were low. It was easy to be the first. And then they would sigh, “Oh, if only we realized how possible everything was back then!”

So, the truth: Right now, today, in 2014 is the best time to start something on the internet. There has never been a better time in the whole history of the world to invent something. There has never been a better time with more opportunities, more openings, lower barriers, higher benefit/risk ratios, better returns, greater upside, than now. Right now, this minute. This is the time that folks in the future will look back at and say, “Oh to have been alive and well back then!”

The last 30 years has created a marvelous starting point, a solid platform to build truly great things. However the coolest stuff has not been invented yet — although this new greatness will not be more of the same-same that exists today. It will not be merely “better,” it will different, beyond, and other. But you knew that.

What you may not have realized is that today truly is a wide open frontier. It is the best time EVER in human history to begin.

You are not late.

 1 Policiais militares prenderam I.J, K.L., e M.N. em maio de 2012 e os levaram ao 58º Batalhão da Polícia Militar de Salvador, no Estado da Bahia. Os suspeitos depuseram em juízo que os policiais os haviam espancado e estrangulado para forçá-los a confessar a posse de drogas e armas de fogo, alegações corroboradas por exames de corpo de delito que mostram diversas lesões em seus rostos, joelhos, cotovelos e peitos no dia de sua prisão.

2 Policiais civis prenderam R.F. em junho de 2012 e o conduziram para a 11ª Delegacia de Polícia. Em depoimento prestado à Corregedoria da Polícia Civil do Estado de São Paulo, R.F. relatou que os policiais o levaram para uma sala no segundo andar da delegacia, onde um deles chutou e desferiu tapas e choques elétricos nos seus braços e pernas para forçá-lo a confessar um furto de máquinas da agência de banco onde trabalhava. Esse relato foi corroborado por um exame de corpo de delito de R.F. realizado na noite dos supostos abusos e por uma testemunha entrevistada pela Human Rights Watch.

3 Em janeiro de 2013, agentes penitenciários obrigaram 52 detentos do Presídio de Vila Velha III, localizado no Estado do Espírito Santo, a se sentarem nus em pisos escaldantes, em retaliação a um protesto por falta de água no presídio. A Human Rights Watch analisou documentos oficiais, fotografias e depoimentos que indicam que vários detentos sofreram queimaduras graves nas nádegas. Um detento relatou à polícia civil que, ao se queixarem das queimaduras, alguns presos foram agredidos e atingidos por spray de pimenta. As autoridades prisionais também suspenderam visitas aos detentos por oito dias após o incidente.

4 No primeiro semestre de 2013, sete policiais do 1o Batalhão da Tropa de Choque de São Paulo, Rondas Ostensivas Tobias de Aguiar (ROTA), detiveram o jovem de 17 anos Z.Z. em sua residência e o levaram para uma delegacia. Após ser liberado por falta de provas, Z.Z. voltou para a delegacia e relatou que os policiais da ROTA o haviam espancado e aplicado choques elétricos em sua barriga por mais de 30 minutos em sua residência, enquanto perguntavam se ele era “um tal de Zabo”. Os policiais teriam ameaçado que “não esqueceriam [dele] e voltariam para queimá-lo” se ele denunciasse os abusos. Em depoimento formal à Polícia Civil, um vizinho de Z.Z. afirmou que “ouviu gemidos e gritos de Z.Z. pedindo para os policiais pararem de bater nele”, e logo em seguida viu os policiais o arrastarem até uma viatura policial com o rosto e a barriga inchados e vermelhos.

5 Quatro jovens com idades entre 22 e 25 anos foram presos em 27 de junho de 2013 depois de supostamente confessarem o estupro e o homicídio de uma menina de 14 anos na região metropolitana de Curitiba, no Estado do Paraná. No entanto, os jovens relataram à Ordem dos Advogados do Brasil (Seção do Paraná), que policiais os levaram a diferentes delegacias onde foram espancados e sufocados, além de receberem choques elétricos, para confessar o crime. Uma semana depois, peritos concluíram que o sêmen encontrado na vítima não correspondia com o DNA dos quatro acusados. Após cobertura extensiva do caso pela mídia nacional, o Grupo de Atuação Especial de Combate ao Crime Organizado do Ministério Público Estadual denunciou 19 policiais e outros agentes pelo crime de tortura contra os suspeitos.

6 Em julho de 2013, Amarildo Dias de Souza (“Amarildo”) desapareceu após ter sido detido por policiais militares na comunidade da Rocinha na cidade do Rio de Janeiro, Estado do Rio de Janeiro. Os policiais afirmaram que soltaram Amarildo e que ele havia deixado a Unidade de Polícia Pacificadora (UPP) da Rocinha a pé. Porém, de acordo com um delegado que apurou o caso, as filmagens das câmeras de segurança do local somente registraram a saída de viaturas policiais. Em outubro de 2013, promotores estaduais ofereceram denúncia criminal contra 25 policiais pela tortura de Amarildo com choques elétricos, asfixia e afogamento com o intuito de forçá-lo a revelar o local onde traficantes de drogas teriam escondido armas de fogo e drogas.

7 Na véspera da prisão de Amarildo, policiais militares levaram o jovem X.Z., de 16 anos, ao Centro de Comando e Controle da Rocinha e o ameaçaram com violência sexual, colocaram sua cabeça dentro de um vaso sanitário cheio de fezes e o forçaram a ingerir cera líquida para que revelasse os nomes de traficantes de drogas, conforme relataram os pais do jovem à Human Rights Watch e ao Ministério Público do Rio em novembro de 2013. Promotores estaduais também denunciaram a tortura do jovem C.D., de 15 anos, que teria sido levado ao mesmo Centro de Comando e Controle em maio de 2013, sufocado com um saco plástico e ameaçado de estupro e morte se ele não revelasse o esconderijo de drogas e armas de traficantes locais.

8 E.F. e G.H., ambos com 17 anos, foram presos em agosto de 2013 por suposto envolvimento com o tráfico de drogas no município de Caieiras, interior de São Paulo. Um vídeo divulgado pela imprensa em outubro mostra vários policiais agredindo E.F. e G.H., perguntando-lhes, “cadê o patrão?” e ameaçando-os, “não chora porque você é homem! Homem não chora”. E.F. declarou que os policiais também o sufocaram com um saco plástico e ameaçaram matá-lo se ele não delatasse os traficantes em Caieiras, segundo o defensor de direitos humanos Ariel de Castro Alves, que entrevistou os jovens logo após sua detenção. O repórter da Ponte, André Caramante, então na Folha de S. Paulo, denunciou o caso.

9 Em agosto de 2013, imagens das câmeras de segurança da unidade da Vila Maria da Fundação Casa em São Paulo, que vazaram para a imprensa, mostraram funcionários da unidade espancando seis jovens após uma tentativa de fuga em maio de 2013. Dois funcionários podem ser vistos chutando e batendo nos adolescentes com seus punhos e cotovelos, enquanto os jovens se encolhem contra uma parede em roupas íntimas, com as mãos para trás. O diretor da unidade e três outros funcionários supostamente envolvidos no episódio foram afastados de seus postos.