Social justice is not an abstract concept that people generate out of thin air, but it develops with the development of society. Under different historical conditions, people do not understand social justice. The Engel Period was brilliant It states: "The fairness of the Greeks and Romans believed that the slave system was fair. " The fairness of the bourgeoisie in 1789 demanded the abolition of the feudal system, because it was said to be unfair . Therefore, the concept of constant fairness not only changed with time and place, but also varies from person to person ". This text states:. ['Social justice is concrete.', 'Social justice is historical.', 'Social justice is relative.', 'Social justice is classy.']