Ontology





In philosophy, ontology, the most fundamental branch of metaphysics, is the
study of being or existence as well as the basic categories thereof. A being
is anything that can be said to 'be' in various senses of the word 'be'. The
verb to be has many different meanings and can therefore be rather
ambiguous. Because "to be" has so many different meanings, there are,
accordingly, many different ways of being.

Aristotle described ontology as "the science of being qua being." The word
'qua' means 'with regard to the aspect of'. According to this theory, then,
ontology is the science of being with regard to the aspect of being, or the
study of beings insofar as they exist. More precisely, ontology concerns
determining what categories of being are fundamental and asks whether, and
in what sense, the items in those categories can be said to "be."

Different philosophers make different lists of the fundamental categories of
being; one of the basic questions of ontology is: "What are the fundamental
categories of being?"

Here are a few more examples of ontological questions:

  1. What is existence?
  2. What are physical objects?
  3. Is it possible to give an account of what it means to say that a
     physical object exists?
  4. What are an object's properties or relations and how are they related
     to the object itself?
  5. Is existence a property?
  6. When does an object go out of existence, as opposed to merely changing?

A few quintessential ontological concepts are:

   * The Problem of universals
   * The Problem of substance