Through the analysis of the contents related to the official evaluations in the unearthed documents with the references of the historical literature,some misunderstandings to the concepts of positive and negative numbers in ancient China could be corrected and the early history of the concepts of the positive and negative numbers could be constructed.This paper pointed out that the standard to judge if the ancient people used the concepts of positive and negative numbers is that the opposite natures were grafted into amounts and became parts of the amounts;argued that the character Suan算 in the Yi医(the Doctor)entry of Suanshu Shu算数书(Writings on Reckoning)could not be a tax unit or a currency unit in general meaning and this entry was neither for the income and tax of a doctor practicing medicine nor for the earning and cost.This paper proved that the Yi entry was the rules defining the lowest ratio of successes to failures of a qualified doctor’s treating cases,and the Suan was the scoring unit for assessing the effects of the treatments of the doctor.By grammatical analyses,this paper proved that the concepts of positive and negative numbers do have been applied in the Yi entry of Suanshu Shu and the Chapter "Kao Gong Ming考功名(Appraise Achievement and official position)" in Chunqiu Fan Lu(Luxuriant Dew of the Spring-and-Autumn Annals)by Dong Zhongshu;however,those suspected cases seen in the wooden slip documents unearthed from the sites of the Han Dynasty in Juyan and Dunhuang are still waiting for confirmation because of insufficient information.This paper argues that the opposite meanings such as gains and losses,successes and failures,etc.were indeed the foundations for the concepts of positive and negative numbers,but the special structure of the Fangcheng(juxtaposed examinations of standards)algorithm in pre-Qin Period was the decisive factor to prompt the emergence of these concepts.The new concepts of positive and negative numbers influenced the evaluation and examination methods to the
