Luddites may be vindicated in the relentless rise of the machines

They collect our tolls, check us out of shops, give us directions, deliver our messages, switch on our lights, guard our homes and even kill our enemies. Smart machines have replaced lots of tasks humans were once paid to perform, with plenty more in the pipeline.The British government recently announced driverless cars will be tested on public roads in Britain by the end of the year. Might cab driving soon b'e another occupation of the past?Economics assumes technological advances are positive because they boost productivity. While new machines often cause economic disruption, history suggests new types of jobs are created and, ultimately, everyone benefits.

But some leading American economists are debating whether smart machines are now destroying jobs faster than new ones are being created.Erik Brynjolfsson and Andrew McAfee, of the Massachusetts Institute of Technology, claim digital technology is restructuring the economy in a way that is "more profound and far-reaching than the transition from the agricultural to the industrial age".People and organisations are falling behind because technology is advancing so fast and, as a result "technological unemployment" is threatening middle-class jobs.In their book Race Against the Machine, Brynjolfsson and McAfee predict gloomy prospects for many occupations as powerful new technologies are adopted not only in manufacturing, clerical and retail but in professions such as law, financial services, education and medicine.

"The pace and scale of this encroachment into human skills is relatively recent and has profound economic implications," Brynjolfsson and McAfee warn. "Perhaps the most important of these is that while digital progress grows the overall economic pie, it can do so while leaving some people, or even a lot of them, worse off."They see rapid technological change contributing to the stagnation of the median i'e and the growth of inequality in the US: "It may seem paradoxical that faster progress can hurt wages and jobs for millions of people, but we argue that's what's been happening."