The designation boshi 博士 "erudite" is documented for the late Spring and Autumn period 春秋 (770-5th cent. BCE). According to Jia Shan's 賈山 biography in the official dynastic history Hanshu 漢書傳, his ancestor Jia Qu 賈祛 had been an erudite in the state of Wei 魏王, and the later counsellor (xiang 相) Gong Yi Xiu 公儀休 (c. 400 BCE) an erudite in the state of Lu 魯, as recorded in the chapter on benevolent officials (59 Xunli liezhuan 循吏列傳) in the history Shiji 史記. There were also erudites in the state of Qi 齊, like Chunyu Kun 淳于髡 (mid-4th cent. BCE). A certain Wei Ping 衛平 (late 6th cent. BCE) is known to have been an erudite in the state of Song 宋 as early as 530 BCE.
During the Qin period 秦 (221-206 BCE) the term boshi was used for a state office. It is known that the First Emperor of Qin 秦始皇 (r. 246-210 BCE) employed seventy erudites that were entrusted with state rituals (dianyi 典義), the imperial library and the exegis of ancient texts and various "skills" (yi 藝). They were particulary used when questions arose about proper rituals and the interpretation of texts. Some of them were experts for the "masters and philosophers" (zhuzi 諸子), including Confucianism, others for poetry, for magic and divination, and others to "connect the past with the present" (zhangtong gujin 掌通古今), i.e. to interprete ancient texts in a way that they were useful for the present. It seems that each person was entrusted with one specialized task. The magicians, for instance, shared among themselves the expertise in the interpretation of dreams or astrology. The Second Emperor of Qin 秦二世皇 (r. 209-207) was more modest and only employed thirty erudites. Their salary was 600 shi 石 "bushels" (see weights and measures) of grain per year.
The Han dynasty 漢 (206 BCE-220 CE) inherited this system in the early decades. Emperor Wen 漢文帝 (r. 180-157 BCE), for example, also employed seventy erudites, each of whom was an expert in one field, including the Confucian Classics, divinatory arts and magical skills. This was a novelty under the early Han. Emperor Jing 漢景帝 (r. 157-141 BCE) employed two erudites as experts for the Classic Shangshu 尚書, namely Zhang Ba 張霸 and Chao Cuo 晁錯 (200-154 BCE), three experts for the Shijing "Book of Songs", namely Shen Pei 申培, Yuan Gu 轅固 and Han Ying 韓嬰, and two experts for the Chunqiu 春秋 "Spring and Autumn Annals", namely Master Humu 胡母生 and Dong Zhongshu 董仲舒 (179-104 BCE). It is not known whether there was an expert for the ritual classics, but there were also some erudites for the Classics Lunyu 論語, Xiaojing 孝經, Mengzi 孟子 and Erya 爾雅.
In 136 BCE Emperor Wu 漢武帝 (r. 141-87 BCE) created the first posts for erudites for the whole corpus of the Five Classics (wujing boshi 五經博士), as state officials in the new National University (taixue 太學). Dong Zhongshu inspired in him the idea to abolish the eruditeships for the "hundred schools" in favour to the Confucian writings. From that time on there were several erudites for individual texts of the Classics. Their doctrines often differed in many substantial points.
Erudites had to develop their own paradigms and to continue a traditional interpretation or even to found a new one (shifa 師法 or jiafa 家法). Under Emperor Xuan 漢宣帝 (r. 74-49 BCE) there were 17 erudites for the Confucian Classics, among them Shi Chou 施讎, Meng Xi 孟喜 and Liangqiu He 梁丘賀 for the Yijing 易經 "Book of Changes", Ouyang Gao 歐陽高 and Xiahou Sheng 夏侯勝 and Xiahou Jian 夏侯建 for the Shangshu, three erudites for the Shijing (the Qi 齊 version of Yuan Gu, the Lu 魯 version of Shen Pei, and the Han 韓 version of Han Ying), Hou Cang 后倉 for the ritual texts, and the schools of the masters Gongyang Gao 公羊高 and Guliang Chi 榖梁赤 for the Chunqiu. Under Emperor Yuan 漢元帝 (r. 49-33 BCE) Jing Fang 京房 was made erudite for the Yijing. Emperor Ping 漢平帝 (r. 1 BCE-5 CE) founded erudite-ships for the Old-Text Shangshu 古文尚書, the Maoshi 毛詩 (a version of the Shijing transmitted by Mao Heng 毛亨 and Mao Chang 毛萇), the "lost chapters on rituals" (Yili 逸禮; such not included in the collection Yili 儀禮), the Yueji 樂記 "Classic of Music", the Zuozhuan 左傳 and the Chunqiu, as well as the two versions of the Gongyangzhuan 公羊家 taught by Yan Pengzu 嚴彭祖 and Yan Anle 顔安樂 (the latter's teachings later divided into the schools of Leng 泠, Ren 任, Guan 管 and Ming 冥), so that the numer of erudites was 30 persons at the time. This was about the number of erudites for the next centuries.
The erudites of the Han period had a high social standing. They were subordinated to the Chamberlain for Ceremonials (taichang 太常) and were regularly consulted by the emperors because their knowledge of the Confucian writings (and virtually of all matters past and present, therefore called boshi "men with broad expertise") was useful for the administration of the state and also for concrete political decisions, in both the central government and in the provinces. Numerous erudites were therefore occasionally dispatched to take over duties similar to that of a regional inspector (cishi 刺史), checking if the administration of the provinces (zhou 州) and the commanderies (jun 郡) was well done. In this function they virtually represented the emperor and had the power to influence the career of local officials, and the duty to discover malfunctions in the system as well as personal misbehaviour of officials. They could therefore be seen as equally important for the emperor as the Counsellor-in-chief (chengxiang 丞相) or the Censor-in-chief (yushi dafu 御史大夫).
The most influential erudites of the Han period were Dong Zhongshu and Gongsun Hong 公孫弘 (200-121 BCE). The latter reformed the system of "chairs", so that each erudite was allowed to educate a fix number of young academics. The number of erudites was fixed (about 17 during the Former and about 14 during the Later Han period), and like with all other state offices, a new appointment could only be made when a vacation was open. The idea was that Confucius himself had had 3,000 disciples, and a similar number of students might be appropriate for an imperial court. The National University therefore accepted the same number of students. By the late Eastern Han period their number had increased to 30,000.
The selection of candidates for the post of erudite therefore required critical consideration of their knowledge of the Classics and ancient writings, and also their moral standing, as described in the regulations for the recommendation and appointment of erudites (baojuzhuang 保舉狀). The Chamberlain for Ceremonials selected among the candidates, and the emperor took over decision which person to appoint. This decision often depended on the number of disciples that a person had and on his scholarly influence. In some cases, candidates from the National University were also asked to take part in a kind of examination to test their knowledge. The best among them were often appointed to posts in the Imperial Secretariat (shangshu 尚書), B-candidates to the post of regional inspector (cishi), and those with mediocre grades to posts like Grand Mentor (taifu 太傅, see Three Dukes) in the households of the nobility (zhuhou 諸侯). Kong Guang 孔光, a fourteenth-generation descendant of Confucius was so good that he was first made a member of the Imperial Secretariat and later promoted to the position of Vice Director (puye 僕射) and then Director of the Imperial Secretariat (shangshuling 尚書令). Candidates were normally aged persons with experience in teaching and learning, yet there were also some exceptions like Dai Pin 戴憑 from the Later Han period who was only 16 sui when he was made an erudite.
During the Han period it was common that an erudite was an expert in only one of the Confucian Classics. This changed during the Wei 曹魏 (220-265) and Jin 晉 (265-420) periods, when it was required that an erudite might be able to interpret all Five Classics as a whole. Holders of boshi posts were to be found as erudites of the Five Classics (wujing boshi), erudites in the Directorate of Education (guozijian boshi 國子監博士) and as such at the National University (taixue boshi 太學博士). Their duty was mainly instruction in the ancient Classics. The erudites under the Chamberlain for Ceremonials (taichang boshi 太常博士) had the lowest standing and were used to provide instructions for state rituals.
The Northern Dynasties 北朝 (386-581) created the offices of erudites for law (lüxue boshi 律學博士) and medicine (yixue boshi 醫學博士).
The designation boshi gradually disappeared during the Sui 隋 (581-618) and Tang 唐 (618-907) periods, and officials were not any more selected from among Confucian scholars, but according to recommendation and by the new selection instrument of the state examinations. Experts in the many practical skills based on ancient writings were called "educated officials" (xueguan 學官) and found jobs in many central government institutions, from the stables (as veterinaries) and as masseurs, to the astronomical office as mathematicians (suanxue boshi 算學博士), or as painters and calligraphers (shuxue boshi 書學博士), and also for the ancestral services. In all prefectures and districts, xueguan were appointed to oversee the local government schools. In contrast to the Han-period erudites, their positions were relatively low. This is also the turning point when the distinguished position of erudite was transformed into that of a teacher (jiaoshou 教授).
In the empire of the Western Xia 西夏 (1038-1227) there were so-called "hundred-methods teachers" (baifa boshi 百法博士) in the Three Schools of Tangutan and Chinese (Fan-Han san xueyuan 蕃漢三學院).
During the Ming 明 (1368-1644) and Qing 清 (1644-1911) periods the term "erudite" was bestowed as a honorific title on the descendants of Confucius, like the title of "Sacred Duke of Yan" 衍聖公, and combined with an official rank (7A and 8A). Yet it continued to be used for erudites under the Chamberlain for Ceramonials, Five-Classics experts in the Directorate of Education, and time measurers (louke boshi 漏刻博士) in the Directorate of Astronomy (qintianjian 欽天監).
Today the term boshi is used for a PhD ("doctor"), and the term jiaoshou for a university professor.