Before defining the term "mythology" one needs to define the meaning of the word "myth". The word itself comes from the Greek "mythos" which originally meant "speech" or "discourse" but which later came to mean "fable" or "legend". In this document the word "myth" will be defined as a story of forgotten or vague origin, basically religious or supernatural in nature, which seeks to explain or rationalize one or more aspects of the world or a society.
Furthermore, in the context of this document, all myths are, at some stage, actually believed to be true by the peoples of the societies that used or originated the myth. Our definition is thus clearly distinguished from the use of the word myth in everyday speech which basically refers to any unreal or imaginary story.
A myth is also distinctly different from an allegory or parable which is a story deliberately made up to illustrate some moral point but which has never been assumed to be true by anyone.
Some myths describe some actual historical event, but have been embellished and refashioned by various story tellers over time so that it is impossible to tell what really happened. In this last aspect myths have a legendary and historical nature.
Definitions of Mythology
For our purposes the word mythology has two related meanings. Firstly it refers to a collection of myths that together form a mythological system. Thus one can speak of "Egyptian Mythology", "Indian Mythology", "Maori Mythology" or "Greek Mythology". In this sense one is describing a system of myths which were used by a particular society at some particular time in human history. It is also possible to group mythologies in other ways. For example one can group them geographically and then speak of "Oceanic Mythology", "Oriental Mythology" and "African Mythology".
A second meaning of the term mythology is the academic study of myths and systems of myths in general.
The types of individual myths and the purpose of mythology
Broadly speaking myths and mythologies seek to rationalize and explain the universe and all that is in it. Thus, they have a similar function to science, theology, religion and history in modern societies. Systems of myths have provided a cosmological and historical framework for societies that have lacked the more sophisticated knowledge provided by modern science and historical investigation.
Creation myths provide an explanation of the origin of the universe in all its complexity. They are an important part of most mythological systems. Creation myths often invoke primal gods and animals, titanic struggles between opposing forces or the death and/or dismemberment of these gods or animals as the means whereby the universe and its components were created.
Apart from an explanation of the creation of the universe, mythologies also seek to explain everyday natural phenomena. The Egyptian scarab god Khepri, who rolled the ball of the sun across the sky each day thus provided an explanation of the rising of the sun each day, its progress across the sky and its setting in the evening. Similarly, the Maori of New Zealand attributed the morning dew to the tears of the god Rangi (Heaven) for the goddess Papa (Earth) from whom he was separated. This class of myth is sometimes called a nature myth.
Myths are also often used to explain human institutions and practices as well. For example, the Greek hero Pelops was reputed to have started the Olympic Games after Poseidon helped him win the hand of Hippodameia in a chariot race. This type of myth is thus etiological. It seeks to account for some human institution through a myth.
Another class of myth is the Theogenic myth. This sets out to delineate the relationships between various gods and other mythical personages and beings who are mentioned in previously existing myths. Theogenic Myths are thus secondary in their purpose. They set out to provide a reinforcement or framework for an existing system of myths. The best known example of this is the Theogeny of Hesiod.
It should not be thought that the functions of myths as delineated above are mutually exclusive. For example creation myths by their very nature are usually Theogenic as well. Myths can, and have, served many purposes. Myths and systems of myths have been created by human beings for many reasons over thousands of years. They are a superb product of humanity collectively and a rich resource for the enjoyment of all mankind. Their fantastic and unreal nature to our modern eyes should not prevent us from enjoying them.