前一阶段,我们学习了简易逻辑.这一部分知识理论性强,课本上有关内容篇幅较少,尤其是命题的否定与否命题这一部分,在学习中感到有一定的困难.为此我们几个同学在老师的指导下,到图书馆、新华书店查阅了有关参考资料.通过研讨,对此有了进一步的理解.我们感到要正确写出一个命题的否命题(对原命题的条件与结论均加以否定)关键是掌握命题的否定(非P)的叙述.而命题的否定的正确表述的关键是正确选定“否定词”, In the previous stage, we learned simple logic. This part of the knowledge is theoretically strong and the content of textbooks is relatively small, especially the part of the proposition of the negation or not. It has certain difficulties in learning. Under the guidance of the teacher, the students consulted the library and Xinhua Bookstore about the reference materials. Through the discussion, this has been further understood. We feel that we must correctly write a proposition of the proposition (conditions and conclusions on the original proposition The key is to grasp the negation of the proposition (non-P). The key to the correct expression of the negation of the proposition is to correctly select the “negative word”.