In this TEDTalk presentation, he argues that the greatest invention of the industrial revolution is the washing machine. Of course, with population growth and the ever-expanding energy and pollution problems, the tree-hugger in you might want to object to such an irresponsible claim... but you forget this is Hans Rosling we're talking about, so there's going to be more to this claim than meets the eye :)
Check out some of his previous presentations here, here and especially here.
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