a 4D climbing wall #dimensions #math #4d #geometry

For a two-dimensional creature climbed this wall, if we intersected it with their world, they would see slices, like round holes that are suspended and don't seem to be connected to anything. They are of course connected in the invisible third dimension. If I move it around, the holes would change, providing some nice variety for their climbing practice. If the board were the slice that intersected with their world, they'd just see a plain wall. And by now you know this 2D example is always an analogy to understand our 3D cells and the mysterious fourth dimension. A four-dimensional climbing wall might look like this to us. We see a three-dimensional web of holes that are suspended and don't seem to be connected to anything. They are of course connected in the invisible fourth dimension. A 40 creature may be so kind as to wriggle it around and provide some variety throughout climbing practice.