Unilineal evolution
（重定向自Classical social evolutionism）
Unilineal evolution (also referred to as classical social evolution) is a 19th-century social theory about the evolution of societies and cultures. It was composed of many competing theories by various anthropologists and sociologists, who believed that Western culture is the contemporary pinnacle of social evolution. Different social status is aligned in a single line that moves from most primitive to most civilized. This theory is now generally considered obsolete in academic circles.