Here are two documents I have written over the summer on beginning to define a “science of cities” or Urban Science.  The first is a “ghostman” outline for a future (5-10 years) textbook on Urban Science that grew out of a workshop on cities at the Santa Fe Institute.  The second is a talk on “Cities as Systems” that I gave at the request of Ralph Dum at the European Forum in Alpbach, Austria in August 2013.