Nothing is as remote as yesterday’s utopias. From the 1990s until the end of the last decade, the explosion in computing power was seen by wide-eyed optimists as a force for liberation that would lay low unaccountable authority. Their eyes have narrowed now. Democracy, justice, our very ability to earn a living, feel precarious. “All that is solid melts into air,” said Marx of 19th-century capitalism. In our times, not only do economic systems feel unstable, but basic assumptions on how humans live together.

Now, and ever more so in the future, how we perceive the world will be determined by what is revealed and concealed by social media and search services, affective computing and virtual reality platforms. The distinction between cyberspace and real space is becoming redundant. The two are merging, and as they come together, companies and states will have the power to control our perceptions. The fragmentation social media promotes has been discussed to death. But it is worth stressing that automated systems are placing us in silos. It is their choice not ours to create a world where the people who most need to hear opposing views are the least likely to hear them. Meanwhile, the scandal of the Brexit campaign is setting the pattern for all campaigns; showing how politcians and their agents can harvest data and target propaganda, tailored to meet its recipients’ prejudices, without any public authority regulating it or even knowing about it.

“You are entitled to your own opinions but not your own facts,” said senator Daniel Patrick Moynihan in the 20th century. If that were ever true, it is not now, as Jamie Susskind shows in this superb and necessary book. Highly unusually, Susskind, a young British lawyer, combines knowledge of technology with knowledge of political theory. He is as comfortable discussing Athenian democracy as the moral problems of having “sex” with a virtual child. His breadth of knowledge allows him to avoid replacing techno-utopianism with fashionable dystopianism, and gives us a work that emphasises that the future depends not just on technical advance but on political choices.

Imagine border police using face-recognition systems that do not recognise that you are you. Photograph: Joe Raedle/Getty Images

For who can argue that the introduction of technologies capable of rapidly disseminating lies does not require a political response. It is not good enough to say Facebook, Google or Twitter are like other private companies, when they have become a modern agora that democratic society has every right to regulate as it regulates other essentials of life. I still subscribe to John Milton and John Stuart Mill’s belief that we should allow free speech to be tested in the marketplace of ideas. But it needs reinterpreting when the marketplace has been partitioned and privatised.

If virtual monopolies are to be tamed, their algorithms cannot be treated as commercially confidential when they order how debates are conducted and information is received. Society must ensure that their rules meet the principles of consent and fairness. As Susskind states, so long as tech firms keep their algorithms hidden, their data policies obscure, and their values undefined, they cannot possibly claim these forms of legitimacy.

The need for openness goes far beyond the tech giants. Already most CVs are never seen by human eyes. Algorithms scan them and decide who should work. If you find a job, algorithms will monitor your performance and determine whether you stay hired or become fired. Your chances of getting a loan or insurance depend on computer programs, as increasingly will every essential of life.

For nearly all of the history of humanity we have lived as an unmonitored species whose deeds were largely forgotten. We are becoming a watched species whose every action, at least in theory, is becoming recordable and retrievable. Those who do the monitoring wield enormous power: a power that is increasingly hard to contest. Imagine the horror of trying to interact with a face-recognition system that does not recognise that you are you. Or look at how the ability to record your past, to rate you as if you were on TripAdvisor, is used in China where local governments are compiling digital records of citizens so the trustworthy can roam where they will while malcontents are confined.

The ability to record your past, to rate you as if you were on Tripadvisor, is used in China

In the west, the algorithms that are ranking people are said to be neutral. Yet Airbnb rules that visitors with African American names are significantly less likely to be accepted than white people with identical credentials. Sentencing algorithms in the US are once again predicting that black offenders are more likely to reoffend than whites. And here lies a distinctly modern arbitrariness: no one can say why. The judge does not give his or her reasons. The code is a commercial secret. The prisoner is sent down by a system that is more Kafkaesque than Orwellian.

Susskind is too intelligent a writer to say that state intervention is the only answer. As China is already suggesting, the new technologies are giving the state powers the dictators of the past could only dream of. Rather, his work leads to demands for transparency. As a working principle it ought to be a given that any form of artificial intelligence that can harm the public must be publicly accountable. If that means opening up commercially confidential information to independent auditors, so be it.

The great debate of the 20th century was how much of our collective life should be controlled by the market. The great debate of the 21st century will be how much should be directed and controlled by digital systems. “We cannot allow ourselves to become the playthings of alien powers, subject always to decisions made for us by entities and systems beyond our control,” concludes Susskind. It is a tribute to him that his work makes that future a little less likely.

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