The process of transitioning from capitalism to socialism involves the establishment of proletarian power and the subsequent construction of socialism. According to Marxist theory, communist society goes through two phases, the lower phase of socialism and the higher phase of communism. The two-stage theory, also known as stagism, proposes that underdeveloped countries must first go through a period of state capitalism before transitioning to socialism. The transitional period, also known as the dictatorship of the proletariat, is necessary to prepare for the eventual shift to communism. Socialism is characterized by common or state ownership and control, and is viewed by Marxists as a transitional stage between capitalism and communism. Feudalism, which had started to take on capitalist elements, was the dominant economic system prior to socialism. This process of transition is necessary to remove the contradiction of ownership and control by a few individuals.