The variety of math used in his body work extends from basic geometric shape to hyperbolic geometry; though there is no need to cover such a wide subject range to explain mathematic influence. Escher was first inspired by the gridded tile patterns, designed in the 14th Century by the Moors, at the Alhambra castle in Granada. Escher was fascinated by the idea of dividing the plane with geometric shapes. Tassellations, the arrangement of closed shapes that do not overlap or allow gaps, became a staple in his work. Typically tassellations are created with regular shapes, such as polygons. Escher was inspired by these patterns and the richness they added to a two dimensional surface, though also understood the geometric concept of three dimensions. Escher was interested in translating the concepts, and line drawings, of space beyond two dimensions to a believable visual depiction. He used many shapes, regular and irregular, that along with a use of certain isometries such as translation and rotation. On the Euclidian plane, N-fold rotational symmetry states that with a particular point (2-D) or axis (3-D) rotation of 360/n the shape/object will not change. Briefly considering some basic variables: the notation for n-fold symmetry is Cn, or solely "n"

the actual symmetry group is specified by the point or access of symmetry, together with the "n" For each point or axis of symmetry the abstract group type is cyclic group Zn of order n, Some groups have the same geometric and abstract notations, in which case distinguish the difference The fundamental domain (smallest part of an object/pattern, which based on symmetry, determines the whole object/pattern) is a sector of 360/n.

*Example without additional reflection symmetry: n = 2, 180 (an example of this would be, yin and yang) *Cn is the rotation group of a regular n-sided polygon in 2-D Note: 1-fold is no symmetry and 2-fold is the most basic symmetry. This isometries determined in this equation alone allowed for a wide variety of patterns; combining additional isometries, such as reflection and gliding reflection, is how Escher created such complex patterns. Going even one step further, Escher created what he called a metamorphosis. He would progressively alter the shapes, letting them slowly distort an interact with each other, and eventually transform/reform into new shapes. His distortions obeyed the 3, 4 or 6-fold symmetry of the original pattern in order to maintain the tassellation. As seen in 'Development 1' , using a number of calculated isometries he progressively transformed a regular polygon into a lizard while maintaining the tassellation. After this technique developed, he added a third dimension; doubling the equations used as well as adding additional geometric and abstract group types. 'Reptiles' is an amazing example of Escher's...