This article reviews the theory of practice that the author has employed for many years, including a discussion of my understanding of the ideas of its original founder Pierre Bourdieu, and my borrowing, expanding, and reinterpreting of his theory. I have long advocated the development of a new “social science of practice,” which is to say, to begin our research from the study of actual practice, on that basis re-examine and reformulate existing theories or generate new concepts, and then return once more to practice to test those. In hindsight, my own research into the biculturality of late-developing China from Western invasion and influence as well as from indigenous tradition, especially as manifested in its changing justice system, has been crucially important to my rethinking of the theory of practice. This article summarizes the key issues and major points involved.