This is my take on the old Four Blind Men and the Elephant tale. Each man feels a different part of the Elephant and describe four totally different (all wrong) animals.
So, below are 3 images of 3 dimensional structures.
Get the pictures?
Each one of these images are compounds of a (the same) single sub-structure! Agree?
Each one of these images is taken of an object with eight identical (except for colour) sub structures.
Now for the hard part…
… each one of these images are of the exact same object! Agree?
So what shape is it and what shape are the 8 components?
How well can you morph the images into a single 3D picture in your head?
Although there are pyramid shaped cavities in the smaller and overall structure there is no ‘unfilled’ space that is not ‘contained’ within the larger object. You could make a solid smaller structure and there would be no spaces within the boundaries of the 8 objects when combined into the larger object.