Why is the first chapter of Das Capital similar to Thermodynamics. It feels like reading a different form of zeroth law.
The zeroth law of thermodynamics states that if two thermodynamic systems each are in thermal equilibrium with a third one, then they are in thermal equilibrium with each other. The law is important for the mathematical formulation of thermodynamics, which needs the assertion that the relation of thermal equilibrium is an equivalence relation. It is needed for a mathematical definition of temperature that will agree with the physical existence of valid thermometers.
Marx basically says the same thing to define the existence of value of a commodity. If the value of two commodities are equivalent to a third one, then their values are equivalent to each other. He establishes the existence of this equivalence of value to commodities and existence of money in society.
