Rosa Luxemburg explains Das Kapital
  A young Rosa Luxemburg explains to her brothers that everything has both a use value and an exchange value, using salt and pepper as examples. Use value is the ability to consume or use something, while exchange value is the ability to trade it for something else, and these two properties are mutually exclusive. Different use values have different qualities, while exchange values have different quantities, and money allows anything to be exchanged for anything, turning all things into commodities. She illustrates simple exchange versus money-mediated exchange, showing how money appears to serve people but in fact makes people serve it. The worth of a thing comes from the human labour that produces it, whether it is salt from a miner or a watch from a jeweller, yet money obscures this reality. Before money, people related directly to each other’s needs; with money, relationships become mediated by possessions. Money makes inequality possible and inevitable, enabling transactions purely for profit, leading to the concentration of wealth and power. The only commodity that always creates profit is human labour power, which capitalists buy to generate surplus value through exploitation. Rosa explains how surplus labour produces profit for the capitalist beyond the worker’s wage, calling this the essence of capital. She criticises the employment of women for lower wages and quotes Marx on the unnatural basis of capitalist relations. She describes the drudgery and exploitation of workers under machinery and modern industry, and urges them to unite to overthrow their oppressors. The scene ends with a humorous domestic interruption, but the point remains: capitalism exploits labour, creates inequality, and can be overthrown through collective action.