Émile Durkheim, a French professor who established the study of sociology in 1887, developed the idea of functionalism throughout his many works published in his lifetime. Durkheim wrote influential works on religion and suicide as well as defined sociological concepts, such as "anomie," which is the decreased interactions of people once a population becomes larger, leading to a loss of norms and culture. Karl Marx's theories on communism and the economy became popular after his death in 1883, and his work has been influential in economics, philosophy, history and social movement courses.
Functionalism sees society (and people) as many parts that work together to perform a specific job, much like the human body or a machine. Therefore, mental states, such as thoughts, desires, happiness and pain, are only reactions to outside stimulation and perceptions of others' mental states and behaviors. More generally, the way we feel and act on our feelings is based on what we believe others are feeling. Marxism provides a lens for sociologists to critique capitalism and its effects on social change and equality. Marx observed how power was used in society in reference to class. The upper class, the bourgeoisie, had the ability to manipulate and take advantage of the lower class, the proletariat. Marx argued that capitalism, profit and maximizing production led to the wide differences in class.
Functionalism oscillates between the beliefs that feelings cause actions and actions cause feelings. It argues that society is stable due to people feeling an emotion (a mental state) and acting a certain way based on that emotion. When other people see those actions, they interpret them internally, which directs their next action, rendering society a constant equilibrium of inputs and outputs. Marx saw societal stability differently, however, believing that money and industry hold the status quo in place. As long as the upper class keeps the lower class happy enough in their oppressed state, the rich will become richer and the lower class will accept their position in life.
Change occurs in functionalism through the entire system understanding the need for the change -- feeling it internally and seeing it happen in other people. Individuals may also see change happening and decide to alter their internal state. For example, you see your city begin to use recycling bins. Even though you have not thought about why you should recycle, you begin to do it. Because others have felt it was necessary and acted on that thought with an ordinance for recycling bin placement, you are now influenced by their actions. Marxism offers a different means of creating change -- conflict and revolution. The lower class must band together and fight the upper class if they want equal rights and suitable working conditions. It is with these theories that the Soviet Union sought to establish a communist state, where everyone received an equal amount of rations and pay.
Both theories are critiqued or their reliance on dualism as a means to explain motivation and change. Functionalism is critiqued for its inability to concretely state how change happens in a functionalist system. The idea of functionalism is stability and constant balance. Functionalism clearly explains how a system or change maintains itself and is reproduced by society. Adherents are less interested in how the change came to be. Similarly, Marxism is criticized for its ideas surrounding change. Marx argued that absolute change can always come from revolutions and class equality. Modern sociologists argue that change has to involve other identities, such as race and gender, and that it does not make sense to put lower classes over other oppressed groups. Marx did not account for motivation and greed in his theories, or that everyone in the group has to want to be in a communist state for the society to function properly.