Many social theories are created by a number of sociologists and anthropologists. These theories deal with social and cultural revolution. Many of them consider technological progress as a primary factor to drive human civilization developments. Morgan divides social evolution in three stages including savagery, barbarism and civilization. These stages can be divided using technological milestones. Fire is a great example of such technological milestone. White suggested that energy is a great measure to judge the human Cultural Revolution.
White strongly believed that harnessing the control over energy is the primary function of culture. According to him, there are five main stages in the process of human development:
Own muscles of humans are used as energy source
Domesticated animals serve the energy
In third stage, energy is derived from plants (agricultural revolution)
Natural resources such as coal, oil, gas are optimized for energy
In final stage, nuclear energy is harnessed
