Platonic solids are regular bodies in three dimensions, such as the cube and icosahedron, and have been known for millennia. They feature prominently in the natural world wherever geometry and symmetry are important, for instance in lattices and quasi-crystals, as well as fullerenes and viruses
Platonic solids have counterparts in four dimensions. Swiss mathematician Ludwig Schlaefli and Alicia Boole Stott showed that there are six of them, five of which have very strange symmetries. Stott, the third daughter of mathematician George Boole, is best known for establishing the term "polytope" for a convex solid in four dimensions, had a unique intuition into the geometry of four dimensions, which she visualised via three-dimensional cross-sections.