Emergence is the arising of new, unexpected structures, patterns, or processes in a self-organizing system. These emergents can be understood as existing on a higher level than the lower level components from which the emergents emerged. Emergents seem to have a life of their own with their own rules, laws, and possibilities unlike the lower level components. The term was first used by the 19th-century philosopher G. H. Lewes and came into greater currency in the scientific and philosophical movement known as emergent evolutionism in the 1920s and 1930s.