One response would be that the maincauseof the French revolution lies outside Mr Garrioch's Paris and beyond the grasp of Mr Jones's elite: in the unrelenting global conflict with Britain that undermined the French state and thrust the country into increasingly unmanageable crises.
The Federal Highway Administration concluded that the maincause was a crack that grew undetected in oneof the bridge's huge chain links, but that the high volume of traffic was also a factor.
For the younger group, onecauseof discouragement is the earned-income tax credit (EITC), America's main anti-poverty tool, which tops up poorer people's pay and thus rewards work.