the buildings and cities we make. These properties are seen over and over in nature, and in cities and streets of the past, but have all but disappeared in the developments and buildings of the last one hundred years. The book shows that living structure depends on features which make a close connection with the human self, and that living structure has the capacity to support human well-being. The Process of Creating Life The second book describes the process of creating "life", which is an evolutionary process. Complex systems do not spring into existence fully formed, but rather through a series of small, incremental changes. The process begins with a simple system and incrementally changes that system such that each change preserves the structure of the previous step. Alexander calls these increments "structure-preserving transformations," and they are essential to his process. Where book one introduces the reader to 15 geometric properties that make up living systems, Alexander reframes those geometric properties as structure-preserving transformations in and of themselves rather than being the results of other transformations. For example, Alexander claims that "Levels of Scale" will arise naturally as a result of structure-preserving transformations, but he notes that "Levels of Scale" can also be viewed as a transformation that introduces level of scale into a given structure. A skilled designer would use this transformation to add depth to a particular part of the system that was being built. Alexander contrasts structure-preserving transformations with "Structure-destroying transformations", which he feels are common in modern architecture. Alexander himself does express some sympathy for those who have used these processes to design buildings that he feels are devoid of "life": "I do not, directly, blame all the architects who have made these buildings in so many places on earth. I believe it is inappropriate to feel anger towards them... Rather, I believe that we must acknowledge that the architects (often our own colleagues) who drew these buildings, and then had them built by methods and processes far from their control, deserve our sympathy for being placed in an impossible position. What has caused the new tradition of structure-destroying forms of this era, are mainly the machine-like processes of planning, conceiving, budgeting, developing, construction contracting, construction labor, and so forth. The architects who fully accepted the modern machine have hardly been more than pawns in the game which is much larger than they are." A Vision