Linear non-equilibrium thermodynamics (NET) provides a compact framework to describe the behavior of systems subject to various driving forces and is fundamentally based on four postulates: 1. the quasi-equilibrium postulate, requiring that gradients are not too large, 2. the linearity postulate, stating that all fluxes are linear functions of all relevant driving forces, 3. Curie's postulate, constraining which fluxes and forces are coupled, and 4. Onsager's reciprocal relations, requiring symmetric coefficient matrices in the flux-force relations.