1. necessities

It refers to the existence, function and inevitability of legal consequences. For example, once a suspended object loses its supporting force, it must land at the same acceleration (9.5 m/s), which is determined by the gravitational properties between objects with mass. The reappearance of the law of two fingers means that no matter when and where, as long as the objective conditions for the law to play its role have not changed and as long as the essential reasons for determining the law have not disappeared, the law will inevitably reappear and play its role. For example, relations of production must adapt to the development of productive forces. Third, it refers to the inevitable vertical and horizontal connection between things. For example, the development and change of one thing will inevitably lead to the change of the corresponding thing.

2. General

Lenin said in Notes on Philosophy: "Law is the same thing in phenomena."

It has a universal dominant effect on the same essential things and phenomena, such as metabolism and changes of seasons, and is applicable to all stages, societies, fields and levels.

3. Objectivity

Laws are objective and can neither be created nor destroyed; Whether people admit it or not, the law always works with its iron inevitability. Idealism either denies the existence of law, or in one way or another describes law as the product of consciousness phenomena such as "absolute spirit" and personal subjective will. They even think that laws are imposed on nature by people. Denying the objective regularity of the development of human society is one of the fundamental characteristics of historical idealism, and it is also the fundamental defect of all ideological systems before the emergence of Marxism. Marx and Engels founded historical materialism and discovered the general law of the development of human society, which made people realize for the first time that human society, like nature, also moves and develops according to its own inherent objective laws. The laws of natural science and social science reflect the objective laws of the development process of objective things. Lenin said: "Law is a lasting thing in phenomena."