Basic Income: A Radical Proposal for a Free Society and a Sane Economy by Philippe Van Parijs and Yannick Vanderborght Harvard University Press, 384 pp., $29.95

The loss of jobs in a high-technology society—and, more than that, the downgrading of skills required and therefore of the wages paid for many of the jobs that remain—are likely to be the primary economic and social challenges facing the United States over the coming generation. The question is not whether millions of would-be workers will be chronically out of work. Unless an outsized legal minimum wage suppresses the availability of entry-level jobs, most Americans will find something to do. But far too many of the jobs they will end up taking will pay them too little to support what our society considers a middle-class standard of living.

The widely touted prospect of driverless vehicles is just one example, but it is illustrative. A half-century ago, the leading opportunity for Americans without a college education to earn a middle-class income, with health and other benefits, was working on a factory floor. But there are many fewer such jobs in the US today—only 8 percent of the country’s labor force works in manufacturing—and fewer still for employees without advanced technical training. In most areas of the country, the best opportunity for these workers is now driving a truck.

Only convinced futurists envision FedEx and UPS vans racing around the nation’s cities anytime soon with no human inside. But in the future, what will the human on board be doing? Most likely, not driving the van but running packages up to people’s doorsteps and then pushing a picture icon on a touch screen to confirm that deliveries have been completed—not so different from what the cashier at a McDonald’s now does. For just this reason, the wages those no-longer-drivers receive also won’t be much different from McDonald’s wages.

Driverless trucks are still some distance in the future, but the reduction of the skills required in the workplace as a result of new technology is already a reality for millions of workers beyond McDonald’s. Today more than 15 million Americans work in some form of retail trade. But apart from the most upscale stores, the job is not what it used to be. Since the introduction of barcode scanners (beginning in the 1970s), most retail sales clerks no longer need to know the store’s inventory, look up prices, keep track of what’s sold in order to facilitate reordering, or even make change in a cash transaction. The job now mostly consists of swiping objects past a scanner and letting a “smart” cash register do the rest.

A similar process is underway in retail-level investing and financial planning. Instead of talking with a broker, many Americans now execute stock trades themselves via E-Trade, and automated “robo-advising” is beginning to take over the more complicated job of helping investors allocate their…