"IN HAMBURG, WE HAD TO PLAY FOR EIGHT HOURS."

1.

The University of Michigan opened its new Computer Center in 1971, in a brand-new building on Beal Avenue in Ann Arbor, with beige-brick exterior walls and a dark-glass front. The university's enormous mainframe computers stood in the middle of a vast white room, looking, as one faculty member remembers, "like one of the last scenes in the movie 2001: A Space Odyssey." Off to the side were dozens of keypunch machines-what passed in those days for computer terminals. In 1971, this was state of the art. The University of Michigan had one of the most advanced computer science programs in the world, and over the course of the Computer Center's life, thousands of students passed through that white room, the most famous of whom was a gawky teenager named Bill Joy.

Joy came to the University of Michigan the year the Computer Center opened. He was sixteen. He was tall and very thin, with a mop of unruly hair. He had been voted "Most Studious Student" by his graduating class at North Farmington High School, outside Detroit, which, as he puts it, meant that he was a "no-date nerd." He had thought he might end up as biologist or a mathematician. But late in his freshman year, he stumbled across the Computer Center-and he was hooked.

From that point on, the Computer Center was his life. He programmed whenever he could. Joy got a job with a computer science professor so he could program over the summer. In 1975, he enrolled in graduate school at the University of California at Berkeley. There, he buried himself even deeper in the world of computer software. During the oral exams for his PhD, he made up a particularly complicated algorithm on the fly that, as one of his many admirers has written, "so stunned his examiners [that] one of them later compared the experience to 'Jesus confounding his elders.' "

Working in collaboration with a small group of programmers, Joy took on the task of rewriting UNIX, which was a software system developed by AT&T for mainframe computers. Joy's version was very good. It was so good, in fact, that it became-and remains-the operating system on which literally millions of computers around the world run. "If you put your Mac in that funny mode where you can see the code," Joy says, "I see things that I remember typing in twenty-five years ago." And do you know who wrote much of the software that allows you to access the Internet? Bill Joy.

After graduating from Berkeley, Joy cofounded the Silicon Valley firm Sun Microsystems, which was one of the most critical players in the computer revolution. There he rewrote another computer language-Java-and his legend grew still further. Among Silicon Valley insiders, Joy is spoken of with as much awe as someone like Bill Gates of Microsoft. He is sometimes called the Edison of the Internet. As the Yale computer scientist David Gelernter says, "Bill Joy is one of the most influential people in the modern history of computing."

The story of Bill Joy's genius has been told many times, and the lesson is always the same. Here was a world that was the purest of meritocracies. Computer programming didn't operate as an old-boy network, where you got ahead because of money or connections. It was a wide-open field in which all participants were judged solely on their talent and their accomplishments. It was a world where the best men won, and Joy was clearly one of those best men.

It would be easier to accept that version of events, however, if we hadn't just looked at hockey and soccer players. Theirs was supposed to be a pure meritocracy as well. Only it wasn't. It was a story of how the outliers in a particular field reached their lofty status through a combination of ability, opportunity, and utterly arbitrary advantage.

Is it possible the same pattern of special opportunities operate in the real world as well? Let's go back over the story of Bill Joy and find out.

2.

For almost a generation, psychologists around the world have been engaged in a spirited debate over a question that most of us would consider to have been settled years ago. The question is this: is there such a thing as innate talent? The obvious answer is yes. Not every hockey player born in January ends up playing at the professional level. Only some do-the innately talented ones. Achievement is talent plus preparation. The problem with this view is that the closer psychologists look at the careers of the gifted, the smaller the role innate talent seems to play and the bigger the role preparation seems to play.

Exhibit A in the talent argument is a study done in the early 1990s by the psychologist K. Anders Ericsson and two colleagues at Berlin's elite Academy of Music. With the help of the Academy's professors, they divided the school's violinists into three groups. In the first group were the stars, the students with the potential to become world-class soloists. In the second were those judged to be merely "good." In the third were students who were unlikely to ever play professionally and who intended to be music teachers in the public school system. All of the violinists were then asked the same question: over the course of your entire career, ever since you first picked up the violin, how many hours have you practiced?

Everyone from all three groups started playing at roughly the same age, around five years old. In those first few years, everyone practiced roughly the same amount, about two or three hours a week. But when the students were around the age of eight, real differences started to emerge. The students who would end up the best in their class began to practice more than everyone else: six hours a week by age nine, eight hours a week by age twelve, sixteen hours a week by age fourteen, and up and up, until by the age of twenty they were practicing-that is, purposefully and single-mindedly playing their instruments with the intent to get better-well over thirty hours a week. In fact, by the age of twenty, the elite performers had each totaled ten thousand hours of practice. By contrast, the merely good students had totaled eight thousand hours, and the future music teachers had totaled just over four thousand hours.

Ericsson and his colleagues then compared amateur pianists with professional pianists. The same pattern emerged. The amateurs never practiced more than about three hours a week over the course of their childhood, and by the age of twenty they had totaled two thousand hours of practice. The professionals, on the other hand, steadily increased their practice time every year, until by the age of twenty they, like the violinists, had reached ten thousand hours.

The striking thing about Ericsson's study is that he and his colleagues couldn't find any "naturals," musicians who floated effortlessly to the top while practicing a fraction of the time their peers did. Nor could they find any "grinds," people who worked harder than everyone else, yet just didn't have what it takes to break the top ranks. Their research suggests that once a musician has enough ability to get into a top music school, the thing that distinguishes one performer from another is how hard he or she works. That's it. And what's more, the people at the very top don't work just harder or even much harder than everyone else. They work much, much harder.

The idea that excellence at performing a complex task requires a critical minimum level of practice surfaces again and again in studies of expertise. In fact, researchers have settled on what they believe is the magic number for true expertise: ten thousand hours.

"The emerging picture from such studies is that ten thousand hours of practice is required to achieve the level of mastery associated with being a world-class expert-in anything," writes the neurologist Daniel Levitin. "In study after study, of composers, basketball players, fiction writers, ice skaters, concert pianists, chess players, master criminals, and what have you, this number comes up again and again. Of course, this doesn't address why some people get more out of their practice sessions than others do. But no one has yet found a case in which true world-class expertise was accomplished in less time. It seems that it takes the brain this long to assimilate all that it needs to know to achieve true mastery."

This is true even of people we think of as prodigies. Mozart, for example, famously started writing music at six. But, writes the psychologist Michael Howe in his book Genius Explained,

by the standards of mature composers, Mozart's early works are not outstanding. The earliest pieces were all probably written down by his father, and perhaps improved in the process. Many of Wolfgang's childhood compositions, such as the first seven of his concertos for piano and orchestra, are largely arrangements of works by other composers. Of those concertos that only contain music original to Mozart, the earliest that is now regarded as a masterwork (No. 9, K. 271) was not composed until he was twenty-one: by that time Mozart had already been composing concertos for ten years.

The music critic Harold Schonberg goes further: Mozart, he argues, actually "developed late," since he didn't produce his greatest work until he had been composing for more than twenty years.

To become a chess grandmaster also seems to take about ten years. (Only the legendary Bobby Fischer got to that elite level in less than that amount of time: it took him nine years.) And what's ten years? Well, it's roughly how long it takes to put in ten thousand hours of hard practice. Ten thousand hours is the magic number of greatness.

Here is the explanation for what was so puzzling about the rosters of the Czech and Canadian national sports teams. There was practically no one on those teams born after September 1, which doesn't seem to make any sense. You'd think that there should be a fair number of Czech hockey or soccer prodigies born late in the year who are so talented that they eventually make their way into the top tier as young adults, despite their birth dates.

But to Ericsson and those who argue against the primacy of talent, that isn't surprising at all. That late-born prodigy doesn't get chosen for the all-star team as an eight-year-old because he's too small. So he doesn't get the extra practice. And without that extra practice, he has no chance at hitting ten thousand hours by the time the professional hockey teams start looking for players. And without ten thousand hours under his belt, there is no way he can ever master the skills necessary to play at the top level. Even Mozart-the greatest musical prodigy of all time-couldn't hit his stride until he had his ten thousand hours in. Practice isn't the thing you do once you're good. It's the thing you do that makes you good.

The other interesting thing about that ten thousand hours, of course, is that ten thousand hours is an enormous amount of time. It's all but impossible to reach that number all by yourself by the time you're a young adult. You have to have parents who encourage and support you. You can't be poor, because if you have to hold down a part-time job on the side to help make ends meet, there won't be time left in the day to practice enough. In fact, most people can reach that number only if they get into some kind of special program-like a hockey all-star squad-or if they get some kind of extraordinary opportunity that gives them a chance to put in those hours.

3.

So, back to Bill Joy. It's 1971. He's tall and gawky and sixteen years old. He's the math whiz, the kind of student that schools like MIT and Caltech and the University of Waterloo attract by the hundreds. "When Bill was a little kid, he wanted to know everything about everything way before he should've even known he wanted to know," his father, William, says. "We answered him when we could. And when we couldn't, we would just give him a book." When it came time to apply to college, Joy got a perfect score on the math portion of the Scholastic Aptitude Test. "It wasn't particularly hard," he says matter-of-factly. "There was plenty of time to check it twice."

He has talent by the truckload. But that's not the only consideration. It never is. The key to his development is that he stumbled across that nondescript building on Beal Avenue.

In the early 1970s, when Joy was learning about programming, computers were the size of rooms. A single machine (which might have less power and memory than your microwave now has) could cost upwards of a million dollars-and that's in 1970s dollars. Computers were rare. If you found one, it was hard to get access to it; if you managed to get access, renting time on it cost a fortune.

What's more, programming itself was extraordinarily tedious. This was the era when computer programs were created using cardboard punch cards. Each line of code was imprinted on the card using a keypunch machine. A complex program might include hundreds, if not thousands, of these cards in tall stacks. Once a program was ready, you walked over to whatever mainframe computer you had access to and gave the stack of cards to an operator. Since computers could handle only one task at a time, the operator made an appointment for your program, and depending on how many people were ahead of you in line, you might not get your cards back for a few hours or even a day. And if you made even a single error-even a typographical error-in your program, you had to take the cards back, track down the error, and begin the whole process again.

Under those circumstances, it was exceedingly difficult for anyone to become a programming expert. Certainly becoming an expert by your early twenties was all but impossible. When you can "program" for only a few minutes out of every hour you spend in the computer room, how can you ever get in ten thousand hours of practice? "Programming with cards," one computer scientist from that era remembers, "did not teach you programming. It taught you patience and proofreading."

It wasn't until the mid-1960s that a solution to the programming problem emerged. Computers were finally powerful enough that they could handle more than one "appointment" at once. If the computer's operating system was rewritten, computer scientists realized, the machine's time could be shared; the computer could be trained to handle hundreds of tasks at the same time. That, in turn, meant that programmers didn't have to physically hand their stacks of computer cards to the operator anymore. Dozens of terminals could be built, all linked to the mainframe by a telephone line, and everyone could be working-online-all at once.

Here is how one history of the period describes the advent of time-sharing:

This was not just a revolution. It was a revelation. Forget the operator, the card decks, the wait. With time-sharing, you could sit at your Teletype, bang in a couple of commands, and get an answer then and there. Time-sharing was interactive: A program could ask for a response, wait for you to type it in, act on it while you waited, and show you the result, all in "real time."

This is where Michigan came in, because Michigan was one of the first universities in the world to switch over to time-sharing. By 1967, a prototype of the system was up and running. By the early 1970s, Michigan had enough computing power that a hundred people could be programming simultaneously in the Computer Center. "In the late sixties, early seventies, I don't think there was anyplace else that was exactly like Michigan," Mike Alexander, one of the pioneers of Michigan's computing system, said. "Maybe MIT. Maybe Carnegie Mellon. Maybe Dartmouth. I don't think there were any others."

This was the opportunity that greeted Bill Joy when he arrived on the Ann Arbor campus in the fall of 1971. He hadn't chosen Michigan because of its computers. He had never done anything with computers in high school. He was interested in math and engineering. But when the programming bug hit him in his freshman year, he found himself-by the happiest of accidents-in one of the few places in the world where a seventeen-year-old could program all he wanted.

"Do you know what the difference is between the computing cards and time-sharing?" Joy says. "It's the difference between playing chess by mail and speed chess." Programming wasn't an exercise in frustration anymore. It was fun.

"I lived in the north campus, and the Computer Center was in the north campus," Joy went on. "How much time did I spend there? Oh, a phenomenal amount of time. It was open twenty-four hours. I would stay there all night, and just walk home in the morning. In an average week in those years, I was spending more time in the Computer Center than on my classes. All of us down there had this recurring nightmare of forgetting to show up for class at all, of not even realizing we were enrolled.

"The challenge was that they gave all the students an account with a fixed amount of money, so your time would run out. When you signed on, you would put in how long you wanted to spend on the computer. They gave you, like, an hour of time. That's all you'd get. But someone figured out that if you put in 'time equals' and then a letter, like t equals k, they wouldn't charge you," he said, laughing at the memory. "It was a bug in the software. You could put in t equals k and sit there forever."