Speaking, he took out a pristine square of white paper from his Space Ring, followed by a signing pen.
"Imagine, this square piece of white paper represents a two-dimensional world."
Su Yu drew a small circle on one edge of the square white paper: "This circle represents a creature living in the two-dimensional world."
"Oh, what comes next?" Sky Dragon said, indicating he understood Su Yu's description.
The concepts of two-dimensional and three-dimensional spaces were not particularly difficult to understand, as she had learned about them from extracurricular books when she was in elementary school.
"Next," Su Yu said, drawing an "X" on the opposite edge of the square directly across the circle: "Let's assume that this 'X' is the destination the circle creature wants to reach."
"Hmm," Sky Dragon acknowledged in understanding.