We are embedded as participants in a patterned system of materials exchange and energy flow, governed by the second law of thermodynamics. In short, 'smart growth' is by definition self-limiting. Infinite growth in a finite system is impossible, and above all, smart growth starts with the affirmation that we must design within the possible in the complex biogeochemical system we inhabit. There are no externalities in an ecosystem so we must abandon sectoral thinking predicated on growth of particular sectors for systems thinking predicated on the stability and self maintenance of the health of the system as a whole. Continuous growth is not possible in healthy organisms or healthy populations.
Continuous growth is, in fact, the unmistakable sign of pathology and imminent death.
As medical doctors point out, continuous growth is the ideology of a cancer cell. It is little wonder that urban policies predicated on the fiction continuous growth leave us with a pattern of urban sprawl that resembles nothing so much as a form of cancer on the land. The ethical principles for smart growth reflect a new and sober assessment of the problematic character of growth and a renewed sense of place for the human prospect in a complex ecosystem. These new evaluations will of necessity involve a profound shift in the core metaphors of Western culture. This ideology of continuous linear expansion toward an ever receeding frontier leaves devastation in its wake, but we do not bother ourselves overly much with the waste stream in the wake of our civilization.