17, Yu Yan advocated "abolishing old doctors and removing medical and health obstacles" for four reasons:

First, the people used by the old doctors now, such as yin and yang, five elements, six qi, viscera and meridians, are all written out of thin air and completely untrue. This should be abolished.

Second, "clinically, it holds the radial artery alone, and mistakenly divides some blood vessels into three parts: inch, clearance and ruler, so as to dominate the viscera, puncture the collaterals and dominate the market." Its origin comes from the study of latitude and longitude, which is different from astronomy and belongs to nonsense. This should be abolished.

Third, "it is simply unknown and cannot be diagnosed. If you investigate the cause of death, you can determine the type of disease and prevent the disease. None of them can get the job. You can strengthen the way of eugenics, and you will be even more ignorant. It is a fundamental plan for the national economy and the people's livelihood and cannot be used for administration at all. It should be abolished.

Fourth, The Evolution of Human Culture was listed as the biggest historical examination question in the Jedi Tiantong, and Zhang suppressed it. The so-called Jedi genius, resisting morality and worshiping personnel, is illusory and practical. After the Northern Expedition, Fang got rid of superstitions and idols in order to make people's thoughts scientific, while the old doctors kept witchcraft prayers for a long time to confuse the people. The government educates the society through cleaning and disinfection, so that people know that micro-bacteria are the source of diseases, while the old doctors insist on the theory of febrile diseases in winter, which is that spring will be warm and summer will hurt summer heat, and autumn heart is worse than malaria and should be abolished.

Therefore, "as long as the old doctors are not removed, the people's thinking will remain unchanged, the new medical cause will not be promoted, and health administration will not progress." For the evolution of the country and the improvement of people's lives, we must take drastic measures. "