Although Upāyakauśalya （ or Upāyakauśalyajñāna ） is a concept originating from Primitive Buddhism, thoughts surrounding this concept has become very important and overwhelming in the first stage of intellectual movements of Mahāyāna Buddhism, and has gradually become a decisive ingredient of the thought of Mahāyāna Buddhism. At the beginning, this article makes a brief review of the texts which centered on the thought of Upāyakauśalya, and then I try to illustrate the spectrums which, included in second chapter of Vimalakirtinirdeśa Sūtra, relate to Upāyakauśalya as well as those miracle act and behavior of Vimalakirti Bodhisattva, a center role in that text. My essential purpose is to show the special character and function of this kind of Upāyakauśalyajñāna, by pointing out that Upāyakauśalya and prajñā is the same one thing with different face and same one substance with different function. Therefore, it carries with a special transcendental character in itself and so that the current prehension telling us Vimalakirti Sūtra is a kind of text which concerned with human being’s real life is not accurate. At last, however, the author intends to outline the idea of Humanism Buddhism founding on the base of pāyakauśalyajñāna.
