Steven D. Levitt - Think like a freak: the authors of Freakonomics offer to retrain your brain ; with a new author Q et A

For E LLEN ,
who has been there for everything,
including the books.

SJD

For my sister L INDA L EVITT J INES ,
whose creative genius amazed,
amused, and inspired me.

SDL

Contents

An endless supply of fascinating questions... The pros and cons of breast-feeding, fracking, and virtual currencies... There is no magic Freakonomics tool... Easy problems evaporate; it is the hard ones that linger... How to win the World Cup... Private benefits vs. the greater good... Thinking with a different set of muscles... Are married people happy or do happy people marry?... Get famous by thinking just once or twice a week... Our disastrous meeting with the future prime minister.

Why is I dont know so hard to say?... Sure, kids make up answers but why do we?... Who believes in the devil?... And who believes 9/11 was an inside job?... Entrepreneurs of error... Why measuring cause-and-effect is so hard... The folly of prediction... Are your predictions better than a dart-throwing chimp?... The Internets economic impact will be no greater than the fax machines... Ultracrepidarianism... The cost of pretending to know more than you do... How should bad predictions be punished?... The Romanian witch hunt... The first step in solving problems: put away your moral compass... Why suicide rises with quality of lifeand how little we know about suicide... Feedback is the key to all learning... How bad were the first loaves of bread?... Dont leave experimentation to the scientists... Does more expensive wine taste better?

If you ask the wrong question, youll surely get the wrong answer... What does school reform really mean?... Why do American kids know less than kids from Estonia?... Maybe its the parents fault!... The amazing true story of Takeru Kobayashi, hot-dog-eating champion... Fifty hot dogs in twelve minutes!... So how did he do it?... And why was he so much better than everyone else?... To eat quickly is not very good manners... The Solomon Method... Endless experimentation in pursuit of excellence... Arrested!... How to redefine the problem you are trying to solve... The brain is the critical organ... How to ignore artificial barriers... Can you do 20 push-ups?

A bucket of cash will not cure poverty and a planeload of food will not cure famine... How to find the root cause of a problem... Revisiting the abortion-crime link... What does Martin Luther have to do with the German economy?... How the Scramble for Africa created lasting strife... Why did slave traders lick the skin of the slaves they bought?... Medicine vs. folklore... Consider the ulcer... The first blockbuster drugs... Why did the young doctor swallow a batch of dangerous bacteria?... Talk about gastric upset!... The universe that lives in our gut... The power of poop.

How to have good ideas... The power of thinking small... Smarter kids at $15 a pop... Dont be afraid of the obvious... 1.6 million of anything is a lot... Dont be seduced by complexity... What to look for in a junkyard... The human body is just a machine... Freaks just want to have fun... It is hard to get good at something you dont like... Is a no-lose lottery the answer to our low savings rate?... Gambling meets charity... Why kids figure out magic tricks better than adults... Youd think scientists would be hard to dupe... How to smuggle childlike instincts across the adult border.

Its the incentives, stupid!... A girl, a bag of candy, and a toilet... What financial incentives can and cant do... The giant milk necklace... Cash for grades... With financial incentives, size matters... How to determine someones true incentives... Riding the herd mentality... Why are moral incentives so weak?... Lets steal some petrified wood!... One of the most radical ideas in the history of philanthropy... The most dysfunctional $300 billion industry in the world... A one-night stand for charitable donors... How to change the frame of a relationship... Ping-Pong diplomacy and selling shoes... You guys are just the best!... The customer is a human wallet... When incentives backfire... The cobra effect... Why treating people with decency is a good idea.

A pair of nice, Jewish, game-theory-loving boys... Fetch me a sword!... What the brown M&Ms were really about... Teach your garden to weed itself... Did medieval ordeals of boiling water really work?... You too can play God once in a while... Why are college applications so much longer than job applications?... Zappos and The Offer... The secret bullet factorys warm-beer alarm... Why do Nigerian scammers say they are from Nigeria?... The cost of false alarms and other false positives... Will all the gullible people please come forward?... How to trick a terrorist into letting you know hes a terrorist.

First, understand how hard this will be... Why are better-educated people more extremist?... Logic and fact are no match for ideology... The consumer has the only vote that counts... Dont pretend your argument is perfect... How many lives would a driverless car save?... Keep the insults to yourself... Why you should tell stories... Is eating fat really so bad?... The Encyclopedia of Ethical Failure ... What is the Bible about?... The Ten Commandments versus The Brady Bunch .

Winston Churchill was rightand wrong... The sunk-cost fallacy and opportunity cost... You cant solve tomorrows problem if you wont abandon todays dud... Celebrating failure with a party and cake... Why the flagship Chinese store did not open on time... Were the Challenger s O-rings bound to fail?... Learn how you might fail without going to the trouble of failing... The $1 million question: when to struggle and when to quit... Would you let a coin toss decide your future?... Should I quit the Mormon faith?... Growing a beard will not make you happy... But ditching your girlfriend might... Why Dubner and Levitt are so fond of quitting... This whole book was about letting go... And now its your turn.

What Does It Mean to Think
Like a Freak?

After writing Freakonomics and SuperFreakonomics, we started to hear from readers with all sorts of questions. Is a college degree still worth it? (Short answer: yes; long answer: also yes.) Is it a good idea to pass along a family business to the next generation? (Sure, if your goal is to kill off the businessfor the data show its generally better to bring in an outside manager.) Whatever happened to the carpal tunnel syndrome epidemic? (Once journalists stopped getting it, they stopped writing about itbut the problem persists, especially among blue-collar workers.)

Some questions were existential: What makes people truly happy? Is income inequality as dangerous as it seems? Would a diet high in omega-3 lead to world peace?

People wanted to know the pros and cons of: autonomous vehicles, breast-feeding, chemotherapy, estate taxes, fracking, lotteries, medicinal prayer, online dating, patent reform, rhino poaching, using an iron off the tee, and virtual currencies. One minute wed get an e-mail asking us to solve the obesity epidemic and then, five minutes later, one urging us to wipe out famine, right now!

Readers seemed to think no riddle was too tricky, no problem too hard, that it couldnt be sorted out. It was as if we owned some proprietary toola Freakonomics forceps, one might imaginethat could be plunged into the body politic to extract some buried wisdom.

If only that were true!

The fact is that solving problems is hard . If a given problem still exists, you can bet that a lot of people have already come along and failed to solve it. Easy problems evaporate; it is the hard ones that linger. Furthermore, it takes a lot of time to track down, organize, and analyze the data to answer even one small question well.