Deductive logic is a tool invented for inference, yet it is also a game played rigorously according to rules.It cannot be justified by any ontology or epistemology.

• 演绎逻辑是人们发明出来的推理工具，同时也是一种严格按照规则进行的游戏，人们对它无法做出本体论或认识论的辩护。