GIScience Ten Years After Ground Truth

Several publications were responsible for the shock waves that ran through the GIScience community in the early 1990s, including the exchanges between Openshaw, Taylor, and Overton ( Openshaw 1991, 1992 ; Taylor and Overton 1991 ), Jordan's comment that GIS was "easily justified but non-intellectual expertise" ( Jordan 1988 ), and Smith's essay on the military roots of GIS ( Smith 1992 ), but none brought them all together better than the book assembled and edited by Pickles (1995 ). Like many others, my initial inclination was to respond to the critiques by defending and counter-attacking, and at Luc Anselin's urging I made an early effort to reply to Taylor's critique ( Goodchild 1991 , Taylor 1990 ). But an invitation from Pickles to write a chapter for his book ( Goodchild 1995 ) was the first indication, to me at least, that a constructive dialog was more likely to help the cause of GIScience, and that the critiques were going to have a lasting impact – GIScience would never again be quite the comfortable retreat for the technically minded that it had been in the past.
Ground Truth had many dimensions, and many more have been added through the publications, conferences, and presentations in the years since it appeared. The four papers in this collection address four of them, but there are many more, and I would like in this commentary both to offer my own thoughts on the four papers, and also to address other issues that stem from the early critiques and continue to demand the attention of GIScience. I would also like to comment on the need for new studies of the impacts of emerging technologies, particularly Google Earth and RFID (Radio Frequency Identification).