理为论的,书论宜理,这是汉魏六朝人在前人论体文写作基础上总结出来的论体文写作原则,既而成为后人习作论体文遵循的规范。尽管后人阐述各异,但“理为论的”写作原则却无更改,成为论体文写作的体制。张相《古今文综·论之体制》云:“载绎其谊,弥纶群言,则作法也;研精一理,则体制也。”①“理”之内 Reason theory, book theory should be reasonable, this is the Han and Wei dynasties on the basis of the predecessors on the basis of physical writing concluded on the principles of physical writing, and thus become the practice of the descendants of the body to follow the norms. Although the descendants elaborate on the differences, there is no change in the writing principle of “theory of reason” and become the system of writing in the physical culture. Zhang Xiang, “The System of Ancient and Modern Literature and Comprehensive Studies” said: "Carrying forward its friendship and making new ideas, then practice it;