On this day, 45 years ago, March 19, 1980 (February 3, 1980, the lunar calendar), Deng Xiaoping proposed the guiding ideology for evaluating historical issues since the founding of the People's Republic of China. On March 19, 1980, Deng Xiaoping reviewed the outline of the "Resolution on Certain Historical Issues of the Party since the Founding of the People's Republic of China" and put forward three guiding principles for the drafting of the "Resolution". First, establish Mao Zedong's historical status and uphold and develop Mao Zedong Thought. This is the core one. Second, we must conduct a truth-seeking analysis of what is correct and what is wrong in history since the founding of the People's Republic of China, including the merits and demerits of some responsible comrades, and make a fair evaluation. Third, we must adopt this resolution to make a basic summary of past events. Summary should be rough rather than detailed. Summarizing the past is to guide everyone to look forward.