According to historical records,most of the ancient saints lived long.The reason may listed as follows: first,the leaders who made outstanding contributions to the development of the human society were regarded as the representatives of the era by ancient people;second,the ancient people had some affection of admiration and thanksgiving for their ancestors,which brought about a course of jinn creation;third,the class of slaves hated the society of exploitation and oppression,and longed for an equal and mutual aiding classless society without exploitation or oppression.