45 years ago today, on December 2, 1980 (October 25, 1980, the lunar calendar), Chen Yun talked about the relationship between "birds and cages." On December 2, 1980, Chen Yun believed that the relationship between "market regulation and planning guidance" was like "birds and cages." There is always a cage in the economy, otherwise the bird will fly away. Chen Yun expressed his views when talking with the Shanghai delegation at the Fifth Session of the Fifth National People's Congress. He said: Revitalizing the economy is to revitalize under the guidance of the plan, not without the guidance of the plan. This is like the relationship between a bird and a cage. A bird cannot be held in your hand, it will die if you hold it in your hand. You must let it fly, but you can only let it fly in the cage. Without a cage, it flew away. If birds are to revitalize the economy, then cages are national plans. Of course, the size of the "cage" should be appropriate and as big as it should be. In addition, the "cage" itself needs to be adjusted, such as revising the five-year plan. But no matter what, there has to be a cage. That is to say, revitalizing the economy and regulating the market can only be carried out within the scope permitted by the plan, and cannot be divorced from the macro guidance of the plan.