Volume I of 'An Introduction to the Great Art', penned by Bel'qualyn Do'neld for zhaunin of Sorcere in great Udos Dro'xun.
To a layman, practicioners of the Great Art appear as gods, wielding powers the layman can only dream of. And such is not far from the truth, for the gods themselves are creatures of power to whom use of the Arts comes as naturally as breath to mortals. The Great Art is the manipulation of the power known as the Weave to create effects of utility and of beauty; mortal students oft split the Great Art into the eight Lesser Arts, that we might narrow our studies and thus be shielded from the true enormity of that which we touch.
Central to the understanding of the Great Art is the understanding of the planes, dimensions or realities which lie alongside and about our own, and thus we will begin our introduction here. Traditional views of the Planes divide them into four categories; Inner, Outer, Transitive and Material. Understanding the relationship between the Planes is impossible to any unable to take their mind beyond the physical limitations of the world one sees and touches; concepts such as "above", "below" and "inside" have deeper meanings in planar theory. Suffice to say that there are two common representations of the relationships between the planes, and both co-exist at once.
The first places the planes as surfaces of a ball. The Inner Planes lie at the center, with the first of the Transitive Planes, the Ethereal Plane, bridging them to the Material Planes. The Material Planes are in turn separated from the Outer Planes by the second of the Transitive Planes, the Astral Plane.
The second places the planes comprising each layer in a spatial relationship to each other. The fulcrum of the diagram becomes the Material Planes, of which our own, the Prime Material, is that with which we are chiefly concerned. About the Prime Material are the Inner Planes, comprising the four Elemental Planes - with fire and water, and earth and air, on opposite sides of the Prime. Above and below are the Positive and Negative planes. The space in which these planes hover is the Astral Plane, and the outer orbit of the diagram contains the numerous Outer Planes, such as the Abyss. The Shadow and Ethereal planes sit alongside the Prime Material, separated along a fourth dimension no physical model can truly illustrate.
Both representations are substantially accurate, yet neither is complete. Such representations, however, assist the student.