Ontology is a branch of metaphysics that focuses on the nature of existence. An ontological study includes consideration of the meaning of existence itself, and involves consideration of entities ranging from individual life forms to the universe as a whole. Within the process of ontology learning, both the physical and the mental realities are explored, since many ontologists see the union of the spirit and the physical as composing one complete entity.
There are different schools of thought that make up the wider metaphysical processes of ontology. Some focus primarily on matters of the spirit, seeking to understand the connection between the soul and a Higher Power, and how that connection relates to the physical plane. Within the context of this exploration, there may be a sub-focus, such as how the union of the spirit with the Higher Power affects the physical well-being of an individual, including how understanding this connection can help to bring about physical as well as emotional healing.
At the core of most approaches to ontology is the question of what it means to exist. This question is applied to the human race as a whole, as well as to the individual. Many institutional religions and the different branches of philosophy employ some form of ontology as they attempt to answer the questions of who we are, where we came from, why are we here, and where will we go after death.
A broader application of ontology theory has to do with simply attempting to understand why people, places, and things relate to and influence one another. This can take the course of attempting to discover on some level the meaning for existence itself, or how to tell the difference between objective and subjective perceptions of reality. Within this approach, an individual action, whether it be a choice made by a human being or the development of a new solar system, is understood to make a strong impression on the future of all existence, even if the action is viewed by mortals as having limited practical significance.
Within this broader range, the role of change in conditions of existence is often taken into consideration. Many ontologists hold that change is inevitable in life of all kinds, and allows evolution to take place at all levels. From this perspective, this means that heavenly bodies continue to evolve and change over the millennia of existence, just as humans do over the course of a lifetime.
The general idea of attempting to define and classify existence has some application in the field of medical informatics. Sometimes referred to as medical ontology, this involves the creation of a well-defined listing of basic concepts that serve as the foundation for evaluation and study of various aspects of physical and emotional health. This approach tends to be more prominent in forms of alternative healthcare, but also has some proponents within traditional medicine.
