Unintended and unplanned consequences

University of Paris Professors Pierre Kopp and Remy Prudhomme made few friends in France when they showed that reallcoating road space from cars to public transit in central Paris did more harm that good. (Ch 13 in this volume but available in French from various sources). Too few Parisians behaved in ways that planners dreamed of and would not switch from autos to buses and trams, even though many more of these were put in service. And we all know what Parisians pay for gasoline.

This morning's WSJ includes "San Francisco Ponders: Could Bike Lanes Cause Pollution?" Well, yes. San Franciscans, like Parisians, do not behave the way planners want them to. Even with new bike lanes, many stick to their cars, but make do with less road space and ebdure slower traffic. So they foul the air all the more.

In Paris as well as San Francisco, central plannning is very hard work, especialy the "green" sort. "Fatal Conceit" or "Law of Unintended Consequences"?