European officials struck a deal yesterday to reopen most of Europe's air space to plane travel as early as this afternoon, assuming Iceland's Eyjafjallajokull volcano continues to subside. This would end the worst peacetime travel disruption in history, a travel crisis that has left thousands of passengers stranded for days and cost the airline industry hundreds of millions of dollars. But in the midst of the chaos and inconveniences, one philosopher took a moment to reflect on what our world would look like without airplanes.