If we look at 2 intersecting orthogonal planes in 3D, the intersection forms a line if you are "living" on either plane. How would the intersection look if there are 2D planes in 4D where the planes do not share a dimension? For example plane 1 exists on X and Y, and plane 2 exists on Z and T. I'm figuring it must be a point if viewed from either plane. Is this correct? The other answer might be there is no intersection, but I don't think this can be correct.