I think here's the argument underpinning all of these. Assumption: Facebook is more effective at capturing attention than TV, TV was more effective than radio,

I think here's the argument underpinning all of these. Assumption: Facebook is more effective at capturing attention than TV, TV was more effective than radio, radio was more effective than newspaper. Follows: If this process continues, at some point we will develop something which captures attention as perfectly as possible. Opinion: That hypothetical end case is most certainly a social ill, especially for democracies. So whether it's Facebook, or whether it's the thing after Facebook, if we keep stepping down this path we're eventually going to end up somewhere very dark.