History of education
Although there are more than 40,000 Chinese characters in written Chinese, many are rarely used. Studies have shown that full literacy in the Chinese language requires a knowledge of only between three and four thousand characters.
Holy Emperor Guan's True Scripture to Awaken the World
"The True Scripture to Awaken the World" is written in simple Classical Chinese, and on the whole it doesn't contain more than 700 Chinese characters. In the first twelve lines, its writing style follows the three-character rule that is popular among other educational Chinese classics, such as "Three Character Classic" and "Standards for being a Good Pupil and Child", then it expands to the four-character rule of Chinese idioms, also known as Chengyu. Usually accompanying the scripture are examples of those who have benefited from the scripture.