Questions of good and evil, right and wrong are commonly thought unanswerable by science. But Sam Harris argues that science can and should be an authority on moral issues, shaping human values and setting out what constitutes a good life.

(I readily agreed, since an unanswerable question is a waste of time.) But no sooner had I asked the Prime Minister how he was than he replied with a grin It s nice to know one doesn t have to fight another election.

Perhaps most important, even as economic growth slows, technological change continues at a breakneck pace, raising seemingly unanswerable questions about its potential impact on the global economy. While some warn that technological progress will leave many unemployed, others remain convinced that displaced workers will find new jobs that do not yet exist, as has occurred in the past.