CHAPTER 1

Improbable world

The world is a complicated and messy place, especially when you consider the complexities we add to it with our carefully constructed environment. Take a really simple act that most of us perform every day without giving it a thought – switching on an electric light. This is clearly not something we are genetically programmed to deal with from birth. Human beings are pretty well identical to the creatures that evolved to survive on the savannah after their ancestors stopped living in trees over 100,000 years ago. Once you get beyond basic bodily functions and activities, the vast majority of our time in the modern world is spent doing things that the human body did not evolve to do. All the rest of our activities and experiences are relatively newly learned. We live unnatural lives.

It’s certainly true that there weren’t many light switches 100,000 years ago. So we all have to learn how to turn the light on – and for most of us (until we venture across the Atlantic and find that they incomprehensibly mount their switches the wrong way up on the wall) it is a natural-seeming, easy act. We flick the switch and the light comes on. No real thought involved. It’s trivial.

But imagine that you had to program a robot from scratch to switch on the light in your living room. You would need to specify exactly where the switch was located. This would involve providing detail of where each wall was, which wall the switch was on, at what height it was located and at what distance it was from the wall’s edge. Alternatively you would need to show your robot exactly what the switch looked like from every possible angle, so the robot could search for it visually. You would also need to specify where and in which direction to apply pressure to the switch, how much pressure to use (it would be embarrassing if the robot snapped the thing off) and when to stop pressing.

What seemed trivial turns out to be anything but a simple task. But more to the point, if you now moved that robot into the hallway and asked it to carry out the same job there, you would have to start all over again. There might be a totally different design of switch with dissimilar physical characteristics. It’s highly unlikely this new switch would be in the same place on the wall in the hall as the switch is in the lounge. Set the robot in action without reprogramming it and you would probably end up with a hole punched in the plaster.

As human beings, we simply can’t afford the time and effort to do the equivalent of re-programming our brains each time we encounter a different light switch. And so we deal with patterns. We don’t learn exactly what each light switch that we encounter is like. Instead we have a broad pattern in mind which specifies ‘This is how you switch on a light using a wall switch’. It enables us to recognise the switch in a broad range of styles and then just to do it – press the switch, get the light. Until some clever designer comes up with a switch that works when you speak to it or touch the lamp itself – and then you have to start the discovery process all over again.

Finding patterns

Of course, we didn’t evolve an ability to recognise patterns to cope with light switches. But exactly the same flexibility of pattern-matching enables us to spot a predator – or a familiar friendly face – even if we have never been in a particular exact circumstance before, and so to take appropriate