僧肇在《肇論》透露出一種獨特的對終極實在的概念，這個觀念貫徹於《肇論》的所有篇章，其中以〈般若無知論〉、〈答劉遺民書〉以及〈涅槃無名論〉三篇對這個觀念有最清晰的展示。對於這個觀念，僧肇在書中常以聖人、聖心、至人、般若、涅槃、無為等概念加以指述。儘管這些概念在文章脈絡中表達不同的重點，但所指的是都是同一。例如聖人、聖心、至人表達其主體義；般若表達其功用義；涅槃和無為則著重於境界義，而所指述的都是同一的真理，即是佛。筆者在此稱之為僧肇的聖人觀。 僧肇在《肇論》中處處展示出聖人的恆常性和健動性，聖人以這種恆常的動為其本質，故筆者稱之為「自然的力動」(Spontaneous Vitality)。「自然」表達其本質性、恆常性；「力動」表示它並非實體，亦非停滯、死寂的存在。 吳汝鈞先生在十多年前開始構思「純粹力動」(Pure Vitality)的觀念，這些年來著作不斷，逐步建立純粹力動現象學的哲學體系。他把東、西方哲學的真理概念概括為實體主義(substantialism)和非實體主義(non-substantialism)兩種路向，並指出前者肯定一絕對有(absolute Sein)作為終極原理，而後者則以絕對無(absolute Nichts)作為終極原理。絕對有包括柏拉圖的理型、基督教的神、黑格爾的絕對精神、印度教的梵、儒家的天道、良知等；絕對無則有佛教的空、禪的無、莊子的逍遙境界、京都學派的絕對無等。吳先生指出，以絕對有或絕對無來指述終極真理，兩者都有其精彩之處，但同時亦有其不足處。絕對有最終可能發展成一種常住論，而絕對無可能會被推展至一種虛無論。他提出的純粹動力則能克服絕對有和絕對無的不足之處，同時亦可綜合二者之優點。 筆者以力動來詮釋僧肇的聖人觀念，無疑是受到純粹力動觀念的啟發。然而，僧肇的聖人觀念跟純粹力動仍頗有相異之處，例如純粹力動透過分化、詐現，現起宇宙萬物，而僧肇則未有提及這種創生性格。本文將嘗試闡釋僧肇的聖人觀以及吳汝鈞的純粹動力觀這兩種終極實在的觀念，並比較兩者的異同。

The Buddhist thought of Seng-chao(僧肇) inherited the teaching of Prajña-sutras and the Mādhyamika School in Indian Buddhism, especially the teaching of Nāgārjuna. He accurately understood the concept of emptiness (śūnyatā) that derived from the Mādhyamika School, and further developed his Buddhist thought with more concern on the relationship between the ultimate reality and the phenomenal world. Seng-chao, in his Chao Lun (《肇論》), demonstrated a special concept of the ultimate reality which can be characterized by seven qualities, namely, transcendence, immanence, permanence, dynamism, soteriology, mindlessness and the capability of knowing everything without worldly cognition. On the other hand, NG Yu-kwan established his philosophical system with Pure Vitality(純粹力動) as the core concept. The Pure Vitality is an expression of the ultimate reality with activity (Aktivität) instead of entity as its basic nature. It can synthesize the advantages of the concepts of Absolute Being (absolute Sein, 絕對有) and Absolute Nothingness (absolute Nichts, 絕對無) because it possesses the qualities of transcendence and creativity of the Absolute Being, and immanence and freedom of the Absolute Nothingness. And, at the same time, it can overcome the two concepts’ shortcomings which are the tendencies toward realism and nihilism respectively. The writer is convinced that Seng-chao’s concept of the Saint should be interpreted as an activity which is, in a sense, similar to the basic nature of NG Yu-kwan’s concept of Pure Vitality and this point deserves a comprehensive study.