This paper includes seven chapters. The first chapter discusses the purport and the structure of Vimalakirti Nirdesa Sutra. Its purport is inconceivable liberation-development and liberation of living beings-purification of Buddha-fields. These three items are one essentially, the inconceivable liberation being the essence of its purport and the development and liberation of living beings and the purification of Buddha-fields being the function of it. Essence and function are identical. This sutra has a structure that goes forward step by step and arranges (...) in a crisscross pattern. The second chapter discusses the thought of sunya. On one hand, this sutra follows and develops the thought of sunya in the Prajn~a^pa^ramita^-su^tra while paying much emphasis on the middle-way sunya, on the other hand, it is characterized by two points in the way of its thought of sunya: all things standing on the root which is baseless and surpassing it within e qu-sunya. The third chapter argues the thought of middle way and non-discrimination. The domain of the bodhisattva embodies the thought of middle way. The thought of middle way of this sutra influenced greatly Na^ga^rjuna who claimed eight-not middle way. Jizang and Zhiyi followed and developed the thought of his. Nonduality is without discrimination. The dharma of nonduality is middle way dharmata^. The theory of dharmata^ is profound and abstruse, being without any form and beyond speech. Entering-the Dharma-door of nonduality has three layers of meaning. Nonduality is inconceivable and entering-the Dharma-door of nonduality is inconceivable liberation. The idea of nonduality of this sutra had a profound impact on Huineng’s Tanjing and Jizang’s thought of nonduality in four-layer two truths. The theory of sunya, middle way and non-discrimination discussed in the above two chapters, is the way of thinking of this sutra which is named as the negative affirming. Without the way of thinking of this kind, no sentient beings were gifted with the great compassion and skill in liberative technique.Without it, there were no developing and liberating living beings and purifying Buddha-fields. The fourth chapter discusses the thought of inconceivable liberation. In general, the Inconceivable is that which is beyond contemplation or conceptualization, beyond linguistic expression. In this sutra, apart from the above significance, the Inconceivable is equal to Liberation. The essence of inconceivable liberation is developing and liberating living beings and purifying Buddha-fields, is being released in liberation without abandoning the passions that are the province of the world, is following the way to attain the qualities of the Buddha, is neither destroying the compounded nor resting in the uncompounded, is being beyond the world without abandoning it. The fifth chapter argues the probability and method of developing and liberating sentient beings, that is, the thought of the Buddha-qualities and skill in liberative technique. The family of the Tathagatas', being constituted by all passions, is different from the true mind, the pure mind, the tatha^gatagarbha or the Buddha-nature. So it is certain that the thought of the Buddha-qualities would develop into the idea which insists on all sentient beings having the Buddha-nature. Zhiyi’s theory of evil-nature was evolved from the thought of the family of the Tathagatas'. The skill in liberative technique has many meanings: (1) A method, a means, a device for saving sentient beings; "expedient means" (upa^ya). "Excellent method for converting beings" (upa^ya-kau/salya). The wisdom of being able to save sentient beings by knowing discriminated phenomena. A temporary teaching established in order to lead sentient beings to the true teaching. This is a subject of primary importance in the Lotus Sutra. (2) A plan, scheme, design (a^rambha). (3) Usage of metaphor in teaching. (4) Chinese Buddhists utilized the doctrine of expedient means to help deal with the hermeneutical problem of reconciling the disparities among the different teachings attributed to the Buddha-to explain that the differences in the teachings of the Buddha delivered in his forty-nine year ministry were the result of the different audiences he addressed. The sixth chapter discusses how to purify the Buddha-fields. When we say that the purity of the Buddha-field reflecting the purity of one’s own mind, the mind is not the transcendental pure one, but the empirical one after arousing the thought of intention to achieve enlightenment. The purity of one’s own mind leading to the purity of the Buddha-field, means that the pure Buddha-field are constructed not only by purifying his own mind but also by purifying all living beings’ minds. Huineng’s idea of “one’s own mind is Buddha immediately” and the argument of “one’s own mind is pure Buddha-field immediately” are greatly different from the thought of the purity of one’s own mind leading to the purity of the Buddha-field. The seventh chapter discusses the relation between this sutra and householder-Buddhism and the secularization of Buddhism. This sutra doesn’t gives theoretical arguments for the householder-Buddhism and the secularization of Buddhism. (shrink)