律师办案中，调查取证、判断事实的过程，就是一个法律推理的过程。律师办案中所涉及的案件事实是过去发生的事实，律师本身并没有亲身经历过，只能通过当事人陈述、调查取证、法庭审理等活动认识它。但当事人的陈述可能不全面甚至虚假，取得的证据可能不充分甚至矛盾，使案 Lawyers handling cases, investigation and evidence collection, to judge the fact that the process is a legal reasoning process. The facts of the cases involved in the handling of cases by lawyers are facts that have occurred in the past. The lawyers themselves have not gone through the activities themselves and can only know about them through activities such as parties’ statements, investigation and evidence collection and court hearings. However, the parties’ statements may not be complete or even false, the evidence obtained may not be sufficient or even contradictory, so that the case