Editing Wallace–Bolyai–Gerwien theorem (section)

== Generalisations ==
The analogous statement about [[polyhedron|polyhedra]] in three dimensions, known as [[Hilbert's third problem]], is false, as proven by [[Max Dehn]] in 1900. The problem has also been considered in some [[Non-Euclidean geometry|non-Euclidean geometries]]. In two-dimensional [[hyperbolic geometry|hyperbolic]] and [[spherical geometry|spherical]] geometry, the theorem holds. However, the problem is still open for these geometries in three dimensions.