There is a proverb in the west: it is difficult for the Ministry of Justice to express its position.

Motto: "Lex noncognitive and impossible Lex nememcogit ad impossible", literally translated as the law does not force the impossible or the law does not force anyone to do the impossible. This reflects the boundary between law and morality. Kant once put forward that "you can do it because you should" (Denn du Sollst). As far as morality is concerned, such strict requirements may be put forward, but in the field of law, especially in the field of criminal law, we can only say "because you can do it, you should do it". The law cannot command people to do the impossible, nor can it forbid people to do the inevitable. This is the basic meaning of this proverb. Justice is the foundation of a country, which is an important legal concept. However, it is undeniable that the concept of justice itself is contradictory. Judging from its requirements, justice excludes arbitrariness, so it shows general justice in principle. However, when justice in a broad sense is applied to specific situations, unfair results often appear. This is the contradiction between generalized justice and individual justice. Legally speaking, the former will bring coldness and rigidity, while the latter will lead to arbitrariness and injustice. But the law must first achieve fairness, with the principle of universal justice and the supplement of individual justice. Law is the norm of society. It is not based on saints and heroes, but on ordinary people and ordinary people. The formation of general and abstract legal norms focuses on broad justice, but at the same time, it takes into account that there can be no just result that harms individualization in the implementation process. Therefore, criminal law establishes general norms and some special norms at the same time, aiming at realizing the coordination between them. When the actor can't carry out legal acts, but just violates the law, he will not be investigated for criminal responsibility, thus avoiding the contradictory relationship between universal justice and individual justice. The maxim "the law cannot be forced" has played such a role. This maxim really rose to the theory of criminal law at the end of 19 and the beginning of the 20th century, that is, the theory of expectation possibility. According to this theory, if the actor can't be expected to carry out legal acts according to the specific circumstances at that time, he can't be identified as subjectively responsible (guilty), so he can't be investigated for criminal responsibility. The criminal law theory of civil law countries holds that the conditions for the establishment of a crime are conformity, illegality and responsibility (or responsibility), and the possibility of expectation is the content of responsibility. However, the lack of anticipatory possibility is not explicitly stipulated in the criminal codes of various countries, and there are also differences on whether the behavior can be declared innocent directly based on the theory of anticipatory possibility in the absence of explicit provisions in the law: Germany generally says that anticipatory possibility is only the theoretical basis of the reasons for excluding liability stipulated in the criminal law, and innocence cannot be declared without explicit provisions in the law. If the theory of expected possibility is applied indefinitely, it may lead to excessive flexibility of criminal law. The author, Professor Zhang Mingkai, also supports the view that the behavior cannot be directly acquitted according to the theory of expected possibility. On the contrary, Japan's general theory holds that the lack of expected possibility is a reason for excluding liability outside the law, that is, innocence can be declared directly without expected possibility. If only the theory of expected possibility is used as the explanation principle of the reasons for excluding liability stipulated in criminal law, the role of this theory can not be fully exerted. Then the author discusses the relationship between expectation possibility and intention and negligence, enumerates three different theories, and points out that cognitive factors and will factors are positive factors of intention and negligence, and expectation possibility is the premise of intention and negligence. When there is no possibility of expectation, it is force majeure, that is, lack of intention or negligence, so the actor does not assume responsibility. There is another difficulty here, that is, the criterion for judging the possibility of expectation. Two problems have arisen: first, what do you mean by "impossible" to implement other legal acts? 2. What are the criteria for judging that the actor cannot perform other legal acts? On the first question, the author draws the conclusion that "other legal acts cannot be carried out" through the investigation of the theory of omission crime, which should be caused by the subjective ability and objective conditions of the actor. There are four main situations: first, due to the objective environment and conditions, other legal acts cannot be implemented; Two, the actor has no subjective ability to implement other legal acts; Three, although other legal acts can be carried out, but he must risk his life; Fourth, although it can be implemented, it must bear the risk of serious physical injury. The latter two cases show that the actor faces great difficulties, just as a legal proverb says, "great difficulties are considered impossible." For the second question, the author expresses his views by discussing three theories of civil law system (actor-based theory, ordinary people-based theory and legal norm-based theory) and their criticism. In his view, the criteria for judging the possibility of expectation should be based on the subjective and personal facts of the actor, and then judged according to the standards of ordinary people in the actor's position. However, the extent to which you can take responsibility should be based on national requirements or legal order. Finally, the author summarizes the meaning of the maxim "law does not oppress people": according to the subjective and personal facts of the actor, when judging that it is impossible for the actor to carry out other legal acts at that time, the law does not require him to carry out legal acts, and even if the actor does not carry out legal acts but carries out prohibited acts, he cannot be investigated for legal responsibility.