Grandfather lived in Yingge. That is a small town famous for its ceramics. Most people in the small town work in making pottery or related work, so there are many kilns in Yingge, and many people also have small kilns at home. Grandfather's job was to use silkscreen to print patterns on tiles, usually, one pattern was printed on four or six tiles and then fired.
So what this picture depicts is: using silkscreen to print patterns on six tiles. But what should I print? Just print: using silkscreen to print patterns on six tiles. Then, what should I print? Still print: using silkscreen to print patterns on six tiles. These were repeated three times.
But this is also like squatting and looking up the ceiling. The near ceiling zooms in, and the far zooms out. The space below is larger and shrinks upward. The door leaf is the same. The bigger one goes down, and the smaller one goes up. It also seems to be a transparent floor. The layout of each layer of the space is the same. We can look down layer by layer. The objects are getting smaller and smaller.