Based on the first four histories of the Chinese classics, namely Shiji, Hanshu, Later Hanshu, and Records of the Three Kingdoms, this book extracts fragments that are particularly relevant to the following five categories or themes, and gives commentaries from a political and strategic perspective. They are: (1) strategic prudence; (2) strategic conservatism; (3) lessons for overstretching or acting recklessly; (4) Mixed and situational grand strategic thinking and practice: (5) Endless grand strategy difficulties. The fundamental thrust of this book is to discover and extract the basic historical lessons of China's foreign strategy, which are based on prudence and strategic conservatism, in line with the Confucian ideology of the philosophical relationship between China and "barbarians", and focus on or prioritize the stability, prosperity, and security of the Chinese state itself, thus paying great attention to the relevance of external objectives, the limits of available capabilities, and the most cost-effective possible. This book adopts a long-standing and frequent commentary-style method in traditional Chinese learning, and is intended to allow readers to make their own judgments and comprehensions as easily as possible based on excerpted fragments of the text.