Shrinking cityShrinking cities or urban depopulation are dense cities that have experienced a notable population loss. Emigration (migration from a place) is a common reason for city shrinkage. Since the infrastructure of such cities was built to support a larger population, its maintenance can become a serious concern. A related phenomenon is counterurbanization. The phenomenon of shrinking cities generally refers to a metropolitan area that experiences significant population loss in a short period of time.
Intuitionistic logicIntuitionistic logic, sometimes more generally called constructive logic, refers to systems of symbolic logic that differ from the systems used for classical logic by more closely mirroring the notion of constructive proof. In particular, systems of intuitionistic logic do not assume the law of the excluded middle and double negation elimination, which are fundamental inference rules in classical logic. Formalized intuitionistic logic was originally developed by Arend Heyting to provide a formal basis for L.