AlphaGo

The game of go is over 3,000 years old. In all that time, it has never been 'solved' as chess has; there are some preferred starting strategies but no optimal overall strategy has ever been developed. The best players have always said that success depends on intuition. This is why, in countries like China and Korea, playing go is regarded as an art.

Once, not so many decades ago, the notion that no computer could ever beat a top human player at chess was a dearly held creed. When that comfort was lost, its adherents quickly turned their attention to go, seen by many as the last bastion of human intellectual superiority. In March 2016, they were forced to accept defeat there too. This is the story of the computer program that did it.

AlphaGo is dfferent from its predecessors. Rather than being supplied with strategies, any advantage stemming from its greater speed in examining possibilities and thus the consequences of the moves open to it, AlphaGo is a neural network which was designed to observe lots of games and learn from them, then play against different versions of itself millions of times, learning at each stage and thus refining its approach. A brief explanation of neural networks is given; like the other technical information here, it's sufficient to contextualise the story, not in-depth enough to distract. The developers who speak to camera are good at communicating what their program does - and what they would like it to do - in terms that will make sense to lay people.

This isn't a film, then, for those interested in the nitty gritty of how work like this is assembled. Rather, its focus is on the philosophical and experiential issues associated with the rise of the machines. It is also, in a curious way, a sports movie. Lee Sedol, widely considered to be the world's greatest living player, agrees to take on AlphaGo in a five game tournament. At first, the young South Korean expects this will be easy. AlphaGo is positioned as the plucky little underdog with big dreams, about to face a brutal reality. But as the first game develops, Sedol begins to doubt himself. He will say afterwards that he has suddenly come to see himself as fighting on behalf of the human race.

With exception of believers in fantastical creatures, humans have, throughout recorded history, been confident of their status as the dominant intellectual force in their environment. Lee Sedol is in a similar position in that, in recent years, he has rarely lost a match, and he has no experience of being crushed. In facing off against AlphaGo, he comes to experience the world in a whole new way, and is forced to make a psychological adjustment that the rest of humanity will also face in due course. The observation of this gives this humble documentary historic importance, and one can only hope that it is not forgotten in the time it takes for the world at large to realise that.

Though talk of singularities and grey goo is wisely kept off the table here, a number of the film's participants express their fear of what these leaps forward in artificial intelligence could mean. It's something partly rooted in rational concern, partly superstitious. Should Charles Babbage have been a watchmaker? The idea that we could pull the plug is charmingly naive. But more interesting is the change that some of them undergo as the story develops, and the strange sense of calm that settles afterwards. Sedol, in his early thirties, walks into the tournament looking like a youth and walks out looking like a man. He has been intellectually stimulated by AlphaGo in a way that's hard for anyone at the top of a game to achieve, and his own ability seems to have grown as a result. All the experienced go players present agree that AlphaGo has given them a new perspective on something they thought they had understood much better than they did.

To understand go is to understand the universe, the old saying goes. Alphago encourages viewers to look at the universe - and all the intellects within it - with a fresh sense of awe.