This book comprehensively introduces the practice and development of the soul of Mao Zedong Thought, including: The soul of Mao Zedong Thought: the living soul of Mao Zedong Thought, the essence of Mao Zedong Thought, pointing out the party's basic work line, and independent revolutionary construction; Mao Zedong Thought of Seeking Truth from Facts: Mao Zedong initiated the practice of seeking truth from facts, established it as the party's ideological line, pragmatic strategy and decision-making, the re-establishment of seeking truth from facts, and the pursuit of truth from facts. New developments in thought; Mao Zedong's mass line thought: initially proposed the mass line thought, gradually formed the mass line thought, further developed the mass line thought, and inherited the mass line in the new era; Mao Zedong's independent thought: initially proposed the independent thought, matured the principle of independence, created a new type of independent diplomacy, inherited and developed the independent thought, and persisted in the advancement of the independent thought.