When compared with the Analects of Confucius, Neo-Confucian philosophy certainly seems a lot more comprehensive and, in some ways, more abstract, doesn't it? But that really shouldn't come as a surprise. As the Confucian tradition developed, innovation and reinterpretation should be expected, bringing out the perceived core teachings and applications of Confucianism in new contexts and under new conditions. The Neo-Confucian emphasis on principle sets out a vision of pure ethical excellence and a goal for self-cultivation in the constant pursuit of becoming a Confucian Junzi, the paragon of virtue and moral exemplar who can realise the ideal harmony and vision in Confucian philosophy. It's important to understand why Zhu Xi is so insistent in distinguishing the abstract realm of Li-Principle from the everyday world that is always an integrated complex of Li-Principle and Qi. If we do not make that distinction, Zhu Xi is saying, we won't be able to understand how moral perfection, the possibility of becoming a sage could be possible. Now, on ethical self cultivation, Zhu Xi turns especially to two other Confucian texts, which originally are chapters of the Confucian Book of Rites or Ritual Practice. Now, these two texts are called the "Great Learning, (Daxue)" and the "Doctrine of the Mean (Zhongyong)." As Neo-Confucianism gained recognition together with the Analects of Confucius and the Mencius, they were then collectively called the Confucian Four Books, which formed the basis of Confucian education from the fourteen to the early twentieth century. You're already familiar with the Analects and the Mencius, and I want to introduce these two other works to you. The Great Learning occupies a very special place in Zhu Xi's reformulation of Confucian philosophy. Now, the title Great Learning conveys the basic sense of higher learning as opposed to, shall we say small or elementary learning for children. But more importantly, it suggests a higher, noble learning for the aspiring Confucian Junzi that is aimed at realizing ethical excellence as distinguished from trivial or ethically inconsequential knowledge. The term "Daxue" in modern Chinese means a university. As it does in modern Japanese, Korean, and Vietnamese, of course, they are pronounced differently in these various languages. The opening chapter of the Great Learning is attributed to Confucius, and the remaining, a commentary attributed to one of Confucius' main disciples. In his influential commentary on the Great Learning, Zhu Xi actually rearranged its content to present a systematic approach to Confucian self-cultivation. The Daxue first identifies the true aim of learning, which in Zhu Xi's reading is to enable, one, the illumination of virtuous character, two, to realise renewal of the people, and three, to find lasting peace in the highest good. Renewal here has the sense of reforming the people, eradicating corruption, and enabling them to become virtuous. So the aim of learning extends from self-cultivation, self-oriented ethical practice to guiding the people towards goodness. To achieve these, again in Zhu Xi's interpretation, that Great Learning spells out eight famous steps. Let's start from the end. The end goal is to bring peace to the world for which order must be established in the individual states that Daxue argues. And to establish order in the state, it is necessary to realise harmony in the family. And to achieve that, one must devote oneself to ethical self- cultivation, that is to say to try to become a Junzi first. So, obviously, how then can ethical self-realisation be attained? The next four steps addressed directly Confucian's self-cultivation. To bring ethical order to oneself, according to the Great Learning, in Zhu Xi's reading, one must seek to rectify one's mind or heart. To do that, it is necessary to render one's thoughts and feelings sincere, and sincerity of thinking and feeling depends on extending knowledge and the extension of knowledge finally rests with the investigation of things. Now, the investigation or examination of things in affairs and the resultant extension of knowledge do not aim at accumulating trivial information. That much, I think, should be clear. Rather, the idea is that the investigation of things would enable us to understand the underlying principles. Knowledge is truly extended only when we understand the Li-Principle that defines reality, what make things the way they are, why people behave the way they do, and how things ought to function, and how people ought to behave. Understanding the Li-Principle of things in other words is never merely a matter of acquiring knowledge of the external world. It may begin with a clear understanding of the nature of things, the operations of Qi, how the vital Qi essence or energies constitute to being of all objects, of all things in the world. But true knowledge naturally extends from the external to the internal ethical world of the mind because Li-Principle applies equally to both as we have already seen in Zhu Xi's analysis. The investigation of things and extension of knowledge would force us, really compel us to see how principles may become distorted and how thoughts, emotions, and actions may be dictated by desire. Equally important, true understanding also enable us to see how the principle and beginnings of goodness are inherent in human nature and how the mind or heart has the capacity to reform itself and realise goodness. In this sense, the investigation of things and extension of knowledge form the beginning of ethical practice. With a clear understanding of the principles of things in affairs including the inherent principles that govern the human heart or mind, then it becomes possible to achieve sincerity of thoughts and feelings according to this argument and our heart and mind that is not moved or perturbed by temptations and desire. Conversely, if we do not investigate and seek to understand, if we do not learn, if we can make heads or tails of why things are or behave in certain ways, and if we don't know how they ought to behave in accordance with principle, then we wouldn't be able to put our thoughts, feelings, and actions in order, and still less those of others. If we fail to understand why we do, what we do, why we so often do what we know we ought not to do, ethical reform would not be possible. The emphasis on learning and intellectual depth and clarity, I think is evident in Zhu Xi's Neo-Confucian philosophy. Some may disagree with it, in fact, even within the Neo-Confucian camp. But there is this fundamental assumption that both natural phenomena and human affairs are ultimately governed by certain fundamental principles. Understanding the world of things and affairs, what is the case? As we saw in our previous discussion, well, it is assumed lead to a better understanding of what ought to be the case. Coming back to the task of self-cultivation, with knowledge and sincerity and the mind not dominated by the ceaseless stirrings of desire, the principle of humanity, the rightness, propriety, and wisdom inherent in the mind would then be able to guide one's thinking, feeling, and action, and make an impact beyond oneself on one's family and society at large.