In the past, book publishing censorship was very strict, but it was still necessary to study foreign knowledge, or use it as critical material. As a result, there were special “internal books” for sale, which only officials or scholars could buy and read. The purpose was to control the publication and circulation of these books.
These internal books usually had words like “Internal distribution, for research only” or “Internal reading material” on them. They required a letter of introduction and a special book purchase certificate, and were purchased at Xinhua Bookstore and registered. The covers of these internal books were special. Yellow covers were for literary content, and gray covers were for political content.
However, during the Cultural Revolution, internal books encountered difficulties. First, because the relevant distribution personnel were convicted of “engaging in revisionism”, the distribution organization was still paralyzed. As a result, the visiting delegation of the “Japan-China Friendship Association” could not see 《Tanaka Kakuei Den》 (Biography of Kakuei Tanaka). Then, some officials’ homes were raided, university libraries were stolen, and grassroots bookstores sold them without authorization, which led to internal books beginning to flow into society.
This had a complex impact on the ideological transformation after the Cultural Revolution. For example, the materials originally used to criticize “Soviet revisionism” made people aware of the similar drawbacks of China and the Soviet Union, guided people to reflect on the Cultural Revolution and the social system, and played a lubricating role in social reform.
Addendum 1: In 1974, Xu Ben, who worked in an electronic instrument factory, read the internally distributed Soviet novel 《The Snowy Winter》. However, he was discovered by Secretary Pan of the superior level, and Xu Ben lost his job. This shows that holding “internal books” without permission was usually not a serious crime, but could be punished.
Addendum 2: Internal books still existed at least in 2010, so some people would use words such as “internal reference” and “reference” as a gimmick to sell books. Therefore, the General Administration of Press and Publication required that the publication of internal books must have a 《Permit for Internal Informational Publications》, and if the rules were violated and distributed to the public, the 《Permit》 would be revoked. This is somewhat similar to the special action notice in 2020 to prohibit “specially supplied” and “exclusively supplied” labeled commodities.
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