provide an accurate yet clear summary of their interpretation of the Tao. A central tenet in most varieties of religious Taoism is that the Tao is ever-present, but must be manifested, cultivated, and/or perfected in order to be realized. It is the source of the Universe, and the seed of its primordial purity resides in all things. The manifestation of the Tao is De, which rectifies and invigorates the world with the Tao's radiance. Alternatively, philosophical Taoism regards the Tao as a non-religious concept; it is not a deity to be worshiped, nor is it a mystical Absolute in the religious sense of the Hindu Brahman. Joseph Wu remarked of this conception of the Tao, "Dao is not religiously available; nor is it even religiously relevant." The writings of Lao Tzu and Chang Tzu are tinged with esoteric tones and approach humanism and naturalism as paradoxes. In contrast to the esotericism typically found in religious systems, the Tao is not transcendent to the self, nor is mystical attainment an escape from the world in philosophical Taoism. The self steeped in the Tao is the self grounded in its place within the natural Universe. A person dwelling within the Tao excels in themselves and their activities. However, this distinction is complicated by hermeneutic (interpretive) difficulties in the categorization of Taoist schools, sects, and movements. Confucian interpretations The Dao, or Way, of Confucius can be said to be "Truth". Confucianism regards the Way, or Truth, as concordant with a particular approach to life, politics, and tradition. It is held as equally necessary and well regarded as De (virtue) and ren (humanity). Confucius presents a humanistic "Dao". He only rarely speaks of the t'ien Dao (Way of Heaven). An influential early Confucian, Hsiin Tzu, explicitly noted this contrast. Though he acknowledged the existence and celestial importance of the Way of Heaven, he insisted that the Dao principally concerns human affairs. As a formal religious concept in Confucianism, Dao is the Absolute toward which the faithful move. In Zhongyong (The Doctrine of the Mean), harmony with the Absolute is the equivalent to integrity and sincerity. The Great Learning expands on this concept explaining that the Way illuminates virtue, improves the people, and resides within the purest morality. During the Tang dynasty, Han Yu further formalized and defined Confucian beliefs as an apologetic response to Buddhism. He emphasized the ethics of the Way. He explicitly