The Great A’Tuin and the Discworld
The novel begins with a description of the world that the plot is set in. In a dimension, “in an astral plane that was never meant to fly” the giant turtle, the Great A’Tuin is set towards its destination. It carries and thinks only of the Weight. That Weight is the Discworld. On top of the Great A’Tuin there are four giant elephants who support the weight of the Discworld.
Most of the weight is of course accounted for by Berilla, Tubul, Great T’Phon and Jerakeen, the four giant elephants upon whose broad and star-tanned shoulders the Disc of the World rests, garlanded by the long waterfall at its vast circumference and domed by the baby-blue vault of Heaven.
The pigment of the imagination
Imagination is regarded to as being an actual, tangible, occurrence in the Discworld. Wizards are the ones who can see imagination and draw their power from it. Imagination is described as a color, the far octarine, which only a few can see and are sensitive to its radiation. Those who can see the pigment of imagination are also susceptible towards seeing other things. They can for example see the physical representation of Death, like Rincewind who is constantly finding ways to escape him (the Death).
The Temple of Bel-Shamharoth and the number eight
Eight is an important number when it comes to wizardry. Not only is the imagination the color eight, but it is connected to the most gruesome of spells that are a part of the Temple of Bel-Shamharoth. The physical representation of the Bel-Shamharoth is not evil, it is worse.
“The Soul Eater. His number lyeth between seven and nine; it is twice four,” Rincewind quoted, his mind frozen with fear.”
Parallel universes
As they are about to fall to their death from a disappearing dragon, Rincewind and Twoflower wake up in another world, in a plane mid-flight heading to the United States. The narrator explains it as while they only appeared there at that moment, they have been in that plane at the same time they were in the Discworld, meaning that there are versions of them existing in parallel universes.
That is to say: while it was true that they had just appeared in this particular set of dimensions, it was also true that they had been living in them all along.
