Abstract: From the view of Albert, the truth means the things that can be criticized rationally and can be verified by facts. According to this view,first, norm should be taken as facts in legal practice. Second, people should set some examining standards based on ration(he calls them as "performance characteristic" or "goal-setting"), and people make their choices between norm and legal planning based on their "background and ration. Thus, the existence of law is rational, and the science of law is scientific, At last, faced with the critiques from the sociological and behavioral, Albert, gives his gainsay. We can. find not only the defeat of Critical Rationalism but also the help it gives us in understanding law.