Judging from its modern incarnation in fiction, a new kind of apocalypse is upon us, one that is both more compelling and more terrifying. Today our fears are broader, deeper, woven more tightly into our daily lives, which makes it feel like the seeds of our destruction are all around us. We are more afraid, but less able to point to a single source for our fear. At the root is the realisation that we are part of something beyond our control. ... In the annals of eschatology, we are living in a golden age. The end of the world is on everyone’s mind. Why now? In the recent past we were arguably much closer to the end – just a few nuclear buttons had to be pushed. ... Humans have always been an organised species. We have always functioned as a group, as something larger than ourselves. But in the recent past, the scale of that organisation has grown so much, the pace of that growth is so fast, the connective tissue between us so dense, that there has been a shift of some kind. Namely, we have become so powerful that some scientists argue we have entered a new era, the Anthropocene, in which humans are a geological force. ... My life depends on technologies I don’t understand, signals I can’t see, systems I can’t perceive. I don’t understand how any of it works, how I could change it, or how it can last. Its feels like peering across some chasm, like I am part of something I cannot quite grasp, like there has been a phase shift from humans struggling to survive to humanity struggling to survive our success.

When I returned to addiction, it was as a scientist studying the addicted brain. The data were indisputable: brains change with addiction. I wanted to understand how – and why. I wanted to understand addiction with fastidious objectivity, but I didn’t want to lose touch with its subjectivity – how it feels, how hard it is – in the process. ... One explanation is that addiction is a brain disease. The United States National Institute on Drug Abuse, the American Society of Addiction Medicine, and the American Medical Association ubiquitously define addiction as a ‘chronic disease of brain reward, motivation, memory and related circuitry’ ... If only the disease model worked. Yet, more and more, we find that it doesn’t. First of all, brain change alone isn’t evidence for brain disease. Brains are designed to change. ... we now know that drugs don’t cause addiction. ... One idea is that addicts voluntarily choose to remain addicted: if they don’t quit, it’s because they don’t want to. ... The view that addiction arises through learning, in the context of environmental forces, appears to be gathering momentum.

Biological systems don’t defy physical laws, of course — but neither do they seem to be predicted by them. In contrast, they are goal-directed: survive and reproduce. We can say that they have a purpose — or what philosophers have traditionally called a teleology — that guides their behavior. ... By the same token, physics now lets us predict, starting from the state of the universe a billionth of a second after the Big Bang, what it looks like today. But no one imagines that the appearance of the first primitive cells on Earth led predictably to the human race. Laws do not, it seems, dictate the course of evolution. ... Animals are drawn to water not by some magnetic attraction, but because of their instinct, their intention, to survive. Legs serve the purpose of, among other things, taking us to the water. ... there appears to be a kind of physics of things doing stuff, and evolving to do stuff. Meaning and intention — thought to be the defining characteristics of living systems — may then emerge naturally through the laws of thermodynamics and statistical mechanics.

It should be emphasised that Europe’s success was not the result of any inherent superiority of European (much less Christian) culture. It was rather what is known as a classical emergent property, a complex and unintended outcome of simpler interactions on the whole. The modern European economic miracle was the result of contingent institutional outcomes. It was neither designed nor planned. But it happened, and once it began, it generated a self-reinforcing dynamic of economic progress that made knowledge-driven growth both possible and sustainable. ... In brief, Europe’s political fragmentation spurred productive competition. It meant that European rulers found themselves competing for the best and most productive intellectuals and artisans. ... A possible objection to this view is that political fragmentation was not enough. The Indian subcontinent and the Middle East were fragmented for much of their history, and Africa even more so, yet they did not experience a Great Enrichment. Clearly, more was needed. ... Political fragmentation existed alongside a remarkable intellectual and cultural unity. ... If Europe’s intellectuals moved with unprecedented frequency and ease, their ideas travelled even faster. Through the printing press and the much-improved postal system, written knowledge circulated rapidly.