Cosmopolitanism is the idea that all human beings are members of a single community. Its adherents are known as cosmopolitan or cosmopolite. Cosmopolitanism is both prescriptive and aspirational, believing humans can and should be "world citizens" in a "universal community". The idea encompasses different dimensions and avenues of community, such as promoting universal moral standards, establishing global political structures, or developing a platform for mutual cultural expression and tolerance.
For example, Kwame Anthony Appiah articulates a cosmopolitan community where individuals from varying locations (physical, economic, etc.) enter relationships of mutual respect despite their differing beliefs (religious, political, etc.). By comparison, Immanuel Kant envisioned a cosmopolitan world where armies were abolished and humans were governed under a representative global institution. In all instances, proponents of cosmopolitanism share an emphasis that all humans should form one cohesive and united community.
In a looser but related sense, "cosmopolitan" is also used to describe places where people of various ethnic, cultural and/or religious backgrounds live together and interact with each other.