形上学(metaphysics)
哲学的分支，其目的在於确定事物的真实本质，确定存在物的意义、结构和原理。在西方哲学史上，对形上学有四种看法：一、是对存在物（如精神和物质）的探求；二、是一种「实在」的科学，与「表象」相反；三、是对世界整体的研究；四、是第一原理（或本体）的理论。形上学的字面意义是「物理学之後」，曾被用於指亚里斯多德着作中亚里斯多德自称的「第一哲学」那部分。亚里斯多德已为哲学家区分了两种任务：研究自然界以及存在於自然界和理性世界的特性，以及探求「存在」以及不动的物质、「不动的行动者」的特点。前一条组成「第二哲学」，主要在他的《物理学》中论述；第二条也叫做「神学」（因为上帝是不动的行动者），在其着作《形上学》中有论述。
English version：
metaphysics
Branch of philosophy whose object is to determine the real nature of things, to determine the meaning, structure, and principles of whatever is insofar as it is. In the history of Western philosophy, metaphysics has been understood as: (1) an inquiry into what sorts or basic kinds of things (e.g., the mental and the physical) exist; (2) the science of reality, as opposed to appearance; (3) the study of the world as a whole; and (4) a theory of first principles. The term means literally “what comes after physics,” and was used to refer to the contents of Aristotle's treatise on what he himself called “first philosophy.” Aristotle had distinguished two tasks for the philosopher: to investigate the nature and properties of what exists in the natural, or sensible, world, and to explore the characteristics of “being as such” and inquire into the character of “the substance that is free from movement,” the unmoved mover. The first constituted “second philosophy” and was carried out primarily in his Physics; the second, which he also called “theology” (because God was the unmoved mover), is discussed in his Metaphysics.