ABSTRACT
Physical environment and its constraints: Human society evolves within, dependent on, and as part of the global environment. Its development is constrained by the conditions of the global environment: available space; waste absorption capacity of soils, rivers, oceans, atmosphere; availability of renewable and non-renewable resources; soil fertility and climate. Some of these are state limitations (depletable resources), others are rate limitations (waste absorption). Sustainable development paths must adhere to these constraints. This is a second restriction c2 of accessibility space.
