Introduction
Koan is considered as one of the representative feature of Zen Buddhism in China, while Zen Buddhism has also been taken commonly as filled with the aura of China. Indeed, koan, as a representative feature, is known famously for its paradoxical character, contradictions and absurdity. Many scholars in various fields have worked on the possibility of understanding the real contexts and natures inside koan. However, I think it is reasonable to understand the theories inside Zen Buddhism mandatory, as to give the account of koan. In this essay, I will try to give an analytic analysis and account on the understanding of complex situation in koan by using western speech act theory. Hence, I would intend to figure out of different possible ways and methods in understanding the usage of koan in Zen Buddhism, under the stance of the intention of communication as a form of rationality. Along with the using of western theories, I would also try to figure out the similarities of koan in Zen Buddhism, along with the other thinking – Taoism in China.

