Dynamic Geometry

In 1938 Lloyd wrote: “Traditionally, geometry has been studied in the tenth grade as a system of rigid, non-flexible elements. The author advances the thesis that all geometric diagrams should be assumed as flexible linkages. …” The writer felt that the use of motion made the geometric materials more lifelike and, hence, more interesting, He also believed that many geometric properties were elucidated more clearly by the flexible models than by similar static ones. Finally, he pointed out that the variance and invariance of certain geometric elements were more easily demonstrated by jointed rather than fixed devices.