Wang was not primarily interested in theoretical issues.  However, some of his comments suggest a subtle metaphysical view that supports his conception of ethics.  This metaphysics is phrased in terms of the Pattern/qi framework (see Section 2, above), and also makes use of the Substance/Function distinction.  Substance (tǐ), literally body, is an entity in itself, while Function is its characteristic or appropriate activity or manifestation: a lamp is Substance, its light is function; an eye is Substance, seeing is its Function; water is Substance, waves are its Function.  The Substance/Function distinction goes back to the Daoists of the Han dynasty (202 BCE–220 CE) and became central among Chinese Buddhists before being picked up by Neo–Confucians. Part of the attraction of this vocabulary is that it gives philosophers drawn to a sort of monism the ability to distinguish between two aspects of what they regard as ultimately a unity.  