Why did Marx argue that wealth was distributed unfairly under capitalism?

Karl Marx argued that wealth distribution under capitalism is inherently unfair because it relies on the exploitation of the working class, or proletariat, by the owners of the means of production, the bourgeoisie.1

Central to this critique is the labour theory of value, which posits that human labour is the sole source of economic value. Marx observed that capitalists pay workers only a subsistence wage—the amount necessary to maintain the worker—while the workers produce goods worth significantly more than that wage. The difference between the value created by the worker and the wage they receive is known as surplus value.231

Marx argued that capitalists unfairly appropriate this surplus value as profit, allowing them to amass vast wealth while workers remain in poverty. This systemic inequality is further reinforced by ideology, which portrays capitalist structures as natural or fair, often obscuring the exploitation occurring within the production process. Ultimately, Marx viewed this as a fundamental contradiction that would lead to the instability and eventual replacement of the capitalist system.132