Commenting the wordless proof: Read each n^3 as n times a square with size (edge length) n. This works perfectly for odd numbers, where the squares can be seen

Commenting the wordless proof: Read each n^3 as n times a square with size (edge length) n. This works perfectly for odd numbers, where the squares can be seen by naked eyes. For the even numbers, one (and only one) square has to be split into two rectangles.