Once upon a time, updates of computer operating systems were of interest only to geeks. You may recall how Version 14.5 of iOS, which required users to opt in to tracking, had the online advertising racketeers in a tizzy while their stout ally, Facebook, stood up for them. Now, the forthcoming version of iOS has libertarians, privacy campaigners and "thin-end-of-the-wedge" worriers in a spin. It also has busy mainstream journalists struggling to find headline-friendly summaries of what Apple has in store for us. "Apple is prying into iPhones to find sexual predators, but privacy activists worry governments could weaponise the feature" was how the venerable Washington Post initially reported it.

Agriculture now has much bigger yields than it did a century ago, but also requires vastly more energy input.Credit: Paulo Fridman/Bloomberg via Getty In 70,000 years, Homo sapiens has grown from thousands of hunter-gatherers teetering on the brink of extinction to a global population of 7.7 billion. In Growth, Vaclav Smil explains how we have peopled the planet through our growing capacity for harvesting energy from our environment: food from plants, labour from animals and energy from fossil fuels. Civilization has developed by dominating Earth's resources. It is high: polluted land, air and water, lost wilderness and rising levels of atmospheric carbon dioxide. He argues that most economic projections predict growth by ignoring the biophysical reality of limited resources.