Professor of security engineering, Computer Laboratory, University of Cambridge; author, Security Engineering

The coming shock isn’t from machines that think but machines that use AI to augment our perception.

For millions of years, other people saw us using the same machinery we used to see them. We have pretty much the same eyes as our rivals, and pretty much the same mirror neurons. Within any given culture, we have pretty much the same signaling mechanisms and value systems. So when we try to deceive or detect deception in others, we’re on a level playing field. I can wear a big penis gourd to look more manly, and you can paint your chest with white and ochre mud stripes to look more scary. Civilization made the games more sophisticated: I signal class by wearing a tailored jacket with four cuff buttons, while you signal wealth by wearing a big watch. But our games would have been perfectly comprehensible to our Neolithic ancestors.

What’s changing as computers become embedded invisibly everywhere is that we all now leave a digital trail that can be analyzed by AI systems. The Cambridge psychologist Michael Kosinski has shown that your race, intelligence, and sexual orientation can be deduced fairly quickly from your behavior on social networks: On average, it takes only four Facebook “likes” to tell whether you’re straight or gay. So whereas in the past gay men could choose whether or not to wear their Out and Proud T-shirt, you just have no idea what you’re wearing anymore. And as AI gets better, you’re mostly wearing your true colors.

It’s as if we all had evolved in a forest where the animals could see only in black and white, and then a new predator came along who could see in color. All of a sudden, half your camouflage wouldn’t work, and you wouldn’t know which half!

At present, this is great if you’re an advertiser, as you can figure out how to waste less money. It isn’t yet available on the street. But the police are working on it; which cop wouldn’t want a Google Glass app that highlights those passersby who have a history of violence—perhaps coupled with W-band radar to see which of them is carrying a weapon?

The next question is whether only the authorities will have enhanced cognition systems or if they’ll be available to all. In twenty years’ time, will we all be wearing augmented-reality goggles? What will the power relationships be? If a policeman can see my arrest record when he looks at me, can I see whether he’s been the subject of brutality complaints? If a politician can see whether I’m a party supporter or an independent, can I see his voting record on the three issues I care about? Never mind the right to bear arms; what about the right to wear Google Glass?

Perception and cognition will no longer be conducted inside an individual’s head. Just as we now use Google and the Internet as memory prostheses, we’ll be using AI systems that draw on millions of machines and sensors as perceptual prostheses.

But can we trust them? Deception will no longer be something that only individual humans do to one another. Governments will influence our perceptions via the tools we use for cognitive enhancement, just as China censors search results, while advertisers in the West will buy and sell what we get to see. How else will the system be paid for?