s likely to be seen with Bono in Africa as in a college classroom, Jeffrey Sachs achieved tenure in Harvard’s economics department at 28 before founding the Earth Institute at Columbia University. In the late 1980s and early ‘90s he advised, with a decidedly mixed record, nations making the transition away from Communist central planning. Today Sachs directs the Millennium Villages Project, an experiment in “sustainable development” that provides massive doses of targeted aid to poor villages. Its many setbacks were the subject of journalist Nina Munk’s The Idealist (2013), which portrays Sachs as hubristic and closed-minded, refusing to learn from others or his own mistakes.

In The Age of Sustainable Development, Sachs seeks to combine his earlier interests in development economics with his more recent environmentalism. The goal is an intellectually rigorous concept of “sustainable development.” Unfortunately, his effort reveals more than the author intends: sustainable development as defined by Sachs is an amalgam of academically fashionable but empirically unsupported notions and preferences.

As a result, the book reads like an alternate-universe version of The Skeptical Environmentalist (2001), Bjorn Lomborg’s point-by-point critique of environmental doom-saying. For Sachs, economic and environmental disaster are always just around the corner. He relies on terms like “planetary boundaries” that must never be “trespassed,” which work better in jeremiads than analyses.

Instead of assessing the costs and benefits of our impact on nature, Sachs treats nature as sacred and immutable. That’s a religious view, not a scientific one. Whether mankind alters the planet beneficially or harmfully is a subjective judgment. Nature, red in tooth and claw, is amoral. Claiming our “walled garden” represents an ideal, fixed, and natural state might be spiritually satisfying, but is an assertion rather than an argument.

Sachs understands sustainable development in Malthusian terms. If we do not change course from our “business as usual strategy,” he warns, we face “calamities, social and environmental.” Yet as Alex Epstein’s The Moral Case for Fossil Fuels (2014) shows, climate- and weather-related deaths have declined dramatically over the last several decades. Sachs, by contrast, doesn’t address the fact that more expensive energy will hinder economic growth, which is necessary to lifting millions out of poverty.

Sachs’s natural resources discussion is similarly unpersuasive. He discusses resource-poor and -rich areas without taking into account the important ways resources are created rather than discovered. Economist Julian Simon famously described humans’ capacity for invention as “the ultimate resource.” America isn’t a leading oil, coal, and natural gas producer just because these resources happen to exist beneath the patch of ground we inhabit. Rather, through advanced technology and free markets we have located and effectively extracted our many resources. In the case of hydraulic fracturing, which Sachs opposes, we “created” new resources where none existed.

Sachs thinks the reason some countries have not developed “is not the result of politics, imperialism or culture—it is a matter of geology.” He contends that hyper-arid regions are poor, for example, but doesn’t discuss Israel. Though largely located in a hyper-arid region, it is one of the world’s most prosperous countries and a leading agricultural producer, relying on high-tech, energy-intensive desalination for 60% of its water. Sachs worries about prospective declines in agricultural yields, a linear extrapolation that excludes the likelihood that farmers will respond to changing weather by planting different crops, and at different times.

Few of Sustainable Development’s prescriptions will convince anyone who didn’t share Sachs’s worldview before reading the book. He criticizes American universities for not being free, and advocates universal preschool. He endorses healthcare as a human right and, quoting the World Health Organization, demands “the highest attainable standard without regard to” a patient’s ability to pay. His definition of malnutrition includes the obese, aggregating those who won’t eat healthily with those who can’t. His denunciations of the Koch brothers and oil companies are all but ritualistic. He attacks urban sprawl and praises density’s environmental benefits. Even if we stipulate his assessment is correct, high-density living appears unattainable without aggressive authoritarianism: time and again, people have moved from cities to suburbs and exurbs when given the choice. Little wonder that the “greenest” cities Sachs’ praises are growing modestly while Austin, Dallas, and Denver, the most carbon-intensive cities on his list, are among America’s fastest-growing.

Sachs does break ranks with leftist activists and social scientists on some questions. He has appreciative things to say about genetically modified foods and the Green revolution, correctly realizes that poverty is declining, and acknowledges (after a good deal of hemming and hawing) that it is to some extent perpetuated by culture and institutions. Naomi Klein and her most avid followers would disagree vehemently with all those positions.

It is, however, possible to be more reasonable and persuasive than Klein and still be unreasonable and unpersuasive. In Nina Munk’s account of the Millennium Villages Project, the law of unintended consequences winds up with the starring role. The moral of that story appears to have been lost on the author of The Age of Sustainable Development.