The decorative patterns are obtained by repeating simple interlocking or overlapping elements.
Together with the taste for symmetry, it provides a dynamic and harmonious effect. For
example the images given above can be replicated multiple times to fill a wall. The design
multiplied on the whole wall will form another image that would look as beautiful as the
individual patch of design.
The detail does not prevail on the whole. There is no tension between reasons, only
equilibrium. The infinite recurrence of the themes is a metaphor for, “eternity fills all” and a
way of capturing the mutability of the universe.
Source:
http://www.researchomatic.com/islamic-architecture-and-geometry-128649.html
2