In mid-November, shortly after 4,000 Minecraft fans descended on Las Vegas for Minecon, the Mojang team held a Q&A session. A young kid was the first to get the microphone. He didn't so much ask a question as offer an idea: pajamas.

Pajamas in Minecraft would be crafted like armor, he explained, but their function would be to help your avatar fall asleep faster. Minecraft's Swedish creator, Markus Persson -- better known as Notch -- smiled politely and handed off the pajamas idea to Jens "Jeb" Bergensten, who was soon to become the lead developer of the game. Jeb played along, suggesting that these pajamas might also make the wearer invisible to monsters.

It was not surprising that the first question at Minecon turned out to be a conversation about a new idea. Minecraft is primarily a game about making new things. Some game reviewers describe it as a sandbox game, which it is, but somehow that designation doesn't capture what makes Minecraft so different.

The breakout panels at Minecon showed just how much Minecrafters really like to make new things: panels offered advice on how to build functional computer circuitry in the game, how to keep monsters from wrecking your buildings, how to build epic architecture with the "wow" factor, and the best strategies for creating multi-player servers.

There was even a panel where Hippoplatimus, a 15-year old who created a "pistons" mod, gave advice to aspiring Minecraft modders. His mod was such a hit that Mojang incorporated it into the game.

When people think of the sandbox genre, they think of games like The Sims, and when it comes to user generated content, they might think LittleBigPlanet -- games with a large variety of outcomes, and games that allow custom maps. Minecraft goes beyond that.

Part of what makes it so special is Notch's direct communication with his player community. Compare, for instance, the 50,000 Twitter followers of Media Molecule (maker of LittleBigPlanet) with the 500,000 followers of Notch. Minecraft players know that Notch, and not some unknown guy in a cubicle, made Minecraft's code. At Minecon, they knew that if he wanted to, Notch could add those pajamas in a heartbeat.

But Minecraft's success is about more than a guy with a signature fedora. As everyone knows by now, with almost zero marketing, Minecraft sold over 4 million copies in two years of open beta. Compare that with LittleBigPlanet's 4.5 million sales -- even as a series backed by a major gaming platform holder.

Notable commentators have offered various explanations of Minecraft's success, and no doubt they are all part right. You can attribute Minecraft's popularity to luck, artistry, accessibility, community, and even authenticity... but let me throw in my own suggestion: those pajamas. More precisely, Minecraft is a hit because it was a game that took the creativity of players just as seriously as it took the creativity of its creator.

My daily work is teaching and research the law of intellectual property. I find Minecraft fascinating because it seems to me that Notch never got the memo on IP that the game industry now knows by heart. Notch made a game that lets players, kids included, feel like they are architects. Minecraft isn't so much a game that shows off the amazing things a game designer did, as it inspires you (even requires you) to make amazing things for yourself. Minecraft is a game about letting people discover their own creativity, even if they have no initial intention of being creative.

In theory, bigger and more experienced studios could have come up with a game like Minecraft years ago. The reason they didn't, I think, is that most developers in the industry have been steeped in the logic and culture of intellectual property. In short, the dominant story of intellectual property is that game developers should make content and players should consume it. And that is right, generally, but it misses out on the potential for players to be creators too.

I should say at the outset that I'm not opposed to intellectual property protection. I teach the law of IP and I have represented IP rights holders in litigation. I firmly believe that IP has been and will continue to be essential to the development of video games as an art form. Ever since the litigation over the Pong patent, copyright, patent, and trademark law have played a key role in allowing game creators to reap the benefits of their creativity.

Intellectual property laws give game makers the right to sue those who pirate, copy, and clone their creative works. Some of the earliest video games, like Pac-Man and Defender, were also the sources of some of the earliest lawsuits over software rip-offs and clones.

Video games actually gave birth to the legal protection of software as a form of intellectual property. In other words, if it were not for Defender and Pac-Man establishing copyright in computer software, Apple and Microsoft would have been historical footnotes, not the economic titans they are today. Companies like Google and Facebook may have never existed.