Each proton has it's own magnetic field so it should effect the magnetic field of all nearby proton whether it is homologous (equivalent) or not. I don't understand how this discrimination arise? How a proton understand - "that proton is like me so I shoudn't .... ... ... " I mean it's ridiculous. In organic chemistry textbooks it says that, non-equivalent proton split signal because they can align either toward or against the magnetic field of a given proton. Now I don't understand why it should only apply to non-equivalent protons? Not to equivalent protons? I am not really getting it. Please help me. Can anyone explain the theory, please?