Courtesy of the National Trust for Historic Preservation. From http://www.planetizen.com/node/36253
The passion for preservation arises out of the need for tangible objects that can support a sense of identity. This theme has already been explored. If we turn to preservationist´s reasons for wanting to maintain aspects of the past, they appear to be of three kinds: aesthetic, moral, and morale-boosting. An old edifice, it is argued, should be saved for posterity because it has architectural merit and because it is an achievement of one forebears. The reason is based on aesthetics, tinged with piety. An old house ought to be preserved because it was once the home of a famous statesman or inventor. Here the appeal is to piety and to the end of building a people´s morale, their sense of pride. An old run-down neighborhood should be saved from urban renewal because it seems to satisfy the needs of the local residents, or because, despite a decaying physical environment, it promotes certain human virtues and a colorful style of life. The appeal is to qualities inherent in established ways and to the people´s moral right to maintain their distinctive customs against the forces of change.
Yi Fu Tuan. Time and Place. P. 197