欧氏几何包括我们高中生学过的平面几何和立体几何 ,但欧氏几何并不是唯一能正确反映物质空间的几何学 .为了开阔同学们的视野、了解几何空间的多样性 ,这里介绍另一种几何———非欧几何 .欧几里得的《几何原本》是欧氏几何的经典著作 .许多人认为《几何原本》中的第五公设 ( Euclidean Geometry includes the plane geometry and solid geometry that our high school students learned, but Euclidean geometry is not the only geometry that can correctly reflect the material space. To broaden the horizons of students and understand the diversity of geometric space, here’s another Geometry - Non-Euclidean Geometry. Euclid’s Geometry Original is a classical work of Euclidean geometry. Many people believe that the fifth geography in Geometry Original (