Max Weber defined rational-legal authority as a form of leadership where power is vested in a particular office or position rather than an individual. This authority is legitimized by a formal system of established laws, rules, and regulations that govern the conduct of both the leaders and the citizens within a bureaucratic structure.

Karl Marx argued that historical change is driven by internal contradictions within the economic base. Each mode of production contains the seeds of its own destruction, which simultaneously creates the conditions for the emergence of the next, more advanced stage of social development.

Karl Marx was critical of Auguste Comte's positivism, which sought to apply the methods of the natural sciences to the study of society to achieve order and progress. Marx favored a dialectical materialist approach, arguing that social change is driven by class conflict and economic contradictions rather than the linear, scientific evolution proposed by Comte.

Marx's concept of the 'fetishism of commodities' refers to the perception of social relations involved in production not as relationships among people, but as economic relationships among the money and commodities exchanged in market trade. This masks the underlying social labor that created the value.

Marx argued that the primary source of unhappiness for the proletariat is alienation. Because workers do not own the means of production and have no control over the products they create, they become estranged from their own labor, the process of production, their fellow workers, and their human potential. This systemic separation from the fruits of their effort is the core of their dissatisfaction.

Marxist historical materialism posits that the economic base of society, specifically the ownership of the means of production (such as factories, land, and tools), determines the superstructure of society, including its laws, politics, and culture. This ownership structure dictates the class relations within a given historical epoch.

Dialectical materialism, a core concept in Marxist theory, posits that social change occurs through the conflict of opposing forces. It suggests that economic systems develop internal contradictions—such as the struggle between the bourgeoisie and the proletariat—which inevitably lead to systemic instability and the transition to a new mode of production.

Many scholars argue that the state-led communism practiced in the USSR and China diverged significantly from Marx's theoretical predictions. Marx envisioned communism as a stateless, classless society emerging from advanced industrial capitalism. The implementation in these nations involved centralized state control and authoritarian structures, which many critics view as fundamentally contrary to Marx's original emancipatory vision.

In Marxist theory, the 'means of production' refers to the physical and non-financial inputs used in the production process, such as raw materials, machinery, tools, and factories. These are distinct from the 'relations of production,' which describe the social relationships between people in the production process.

Marx predicted that capitalism would lead to the concentration of wealth in the hands of the bourgeoisie while the proletariat would grow in size and misery. This widening gap, or polarization, would eventually lead the working class to recognize their shared exploitation, fostering class consciousness and setting the stage for revolutionary change against the capitalist structure.