Introductory remarks

Philosophy is traditionally divided into metaphysics (ontology), epistemology (the study of knowledge) and axiology the study of values (ethics + aesthetics). Metaphysics is variously characterized as a study of reality itself, of what exists, of being. It is the study of reality as opposed to appearances.

The word “metaphysics” derives from the Greek “ta meta ta physica” (literally "what comes after physics"), which was the title of one of Aristotle’s treatises that followed the one devoted to physics. Aristotle never used this term. However, he used the term “first philosophy” and he explained it twofold.

First: as a knowledge of first causes. The central notion of Aristotle's first philosophy was God, or the Unmoved Mover.

Second: as the study of ‘being qua being” (being as such). This is a universal science that considers all the objects that there are. It also deals with very general notions that apply to all beings: identity, similarity, difference. Moreover, it delineates general classes of being, called categories.

Metaphysics is concerned with what is required for something to exist: the nature of things. One of the central questions of metaphysics is: what kinds of things are there? Are there any types of things other than ordinary physical objects? For instance properties: things that physical objects have in common. Do they exist, or is the talk about properties merely metaphorical?

Examples of categories of objects that are analyzed by ontology are: concretes, abstracts,  universals, particulars, sets, numbers, events, minds. 

An important part of metaphysics is an analysis of the fundamental structure of the material world. The fundamental categories with the help of which we describe the physical world are the categories of time, space, and causation. Philosophy of time forms a central part of modern metaphysics.  It considers, among others, the following questions: Is the passing of time real or illusory? Do past and future events exist? Is time an independent substance, or does it depend ontically on the material world? In considering these and other metaphysical questions about the nature of time we should takie into account the advancements of modern science, in particular physics. Especially the development of the special and general theories of relativity had a significant impact on the modern metaphysics of time.