Depending who you ask, the tech behind bitcoin could reinvent capitalism or cover criminal tracks. The bigger concern is what it’s doing to the planet…

By Douglas Heaven

RARELY before has such an obscure and complex technology captured the popular imagination quite like the one announced in a nerdy corner of the internet in 2008 by its inventor, Satoshi Nakamoto, a mysterious person or persons whose real identity still isn’t known for certain.

The metaphors used to describe the blockchain are appropriately grabby, too. It’s a mind virus. It’s the internet of money. It’s the end of capitalism.

Or think of it like a bicycle, says Nolan Bauerle of the cryptocurrency news site Coindesk. “We had wheels and chains and saddles, but the magic happened when the thing was made to roll on two wheels and everyone said, ‘Oh my goodness, I didn’t think that was possible’.”

All clear? Well, this much we do know: the blockchain was invented to build trust in the first cryptocurrency, bitcoin, a digital and decentralised way to move money. Bitcoin’s roots are in anarcho-capitalism, a movement that aspires to reproduce the mechanisms of the free market without the need for banks or state bodies to enforce rules. “It was designed to get governments and law enforcement out of the way,” says William Knottenbelt at Imperial College London.

Blue-chip buzzword

In effect, the blockchain is simply a database. It stores arbitrary information such as bitcoin transactions in units called blocks. New blocks get stuck to the end of an ever-growing chain via some heavyweight number-crunching, and are copied to many …