毋意 means not to engage in guessing and speculation. There must be evidence supporting every belief. 毋必 means to have no absolutes; nothing should be cast in stone. Always leave some room for qualifiers and adjustments. 毋固 means not to be stubborn and struggle to defend the indefensible. It’s a waste of energy. 毋我 means not to be too subjective in one’s judgement. Always refer to the facts.