هم‌گرايي سه گونه بنيادين هندسي و پيدايش هندسه مسجد ايراني

Convergence of Three Fundamental Geometric Types& Genesis of the Persian Mosque’s Geometry

چگونگي پيدايش هندسه مسجد چهارايواني گنبددار يا مسجد ايراني در هاله‌اي از ابهام است و گونه‌شناسي متداول مساجد ايران برمبناي شمار ايوان‌ها نيز از اين ابهام نمي‌كاهد. هندسه، جان‌مايه هر نوع معماري است كه با تعريف و تحديد آن، درك كالبدهاي گونه‌گون آن نوع را آسان‌تر مي‌كند. بنابراين براي شناخت شكل ايراني مسجد، بهتر است از چيستي سرچشمه‌هاي هندسي و چگونگي فرآيند پيدايش هندسه آن نيز پرسيد. مقاله در آغاز، كهن‌الگوي مسجدها را بررسي و دگرگوني آن را هنگام ورود به ديگر سرزمين‌ها بيان مي‌كند. سپس با شناسايي شماري از نخستين مسجدهاي ايران، به جست‌وجوي سرچشمه‌ها برآمده، به چگونگي پديداري اين مسجدها از ديدگاه هندسي پرداخته و دستاوردهاي اين تجربه‌هاي نخستين را براي سده‌هاي پسين برشمرده است. در ادامه، با بررسي مساجد ساخته شده در نيمه نخست هزاره اول هجري و با نماياندن ردپاي سه گونه هندسي به‌دست آمده از دوره پيشين، به دسته‌بندي و تحليل هر گونه مي‌پردازد. سپس دو گرايش بعدي ميان اين گونه‌ها شناسايي و به نمونه‌هاي آن تا روزگار كنوني اشاره مي‌شود. سرانجام، با پردازش فرآيند تاريخي گرايش به هم‌گرايي در يكي از نخستين كارگاه‌هاي تجربي، نشان داده كه پيدايش چنين هندسه‌اي براي مسجد ايراني، برآيند هندسي آن سه گونه بنيادين مسجد در ايران است.

The Persian mosque has been much studied, but little from geometrical aspect. The genesis of the geometry of domed four-eivan (four-veranda) mosque, called the Persian mosque, is ambiguous. Common typology of mosques in Iran, based on the number of eivans, counting from one to four, will not solve the problem, and results in several drawbacks: First, the relation between the Persian mosque and the history of Persian architecture remains ambiguous and problematic; second, some mosques in Iran are not domed four-eivan mosques, so discussed typology results some exceptions and disagreements; third, the conspicuous spatial differences between domed and non-domed mosques in their facade of eivan are neglected. If architecture can be seen as a system of organs gathered together based on a coherent order, geometry is the grasp of the relation between and, finally, the system of contiguity of the organs. Therefore, geometry is the essence of all architecture; by defining and delimiting each function, it simplifies understanding of it. So, to gain knowledge of the Persian version of mosque, studying its roots is necessary. This article analyzes the archetypal mosque, namely the Mosque of the Prophet, in its primary form. Describing the geometrical features of it, it then studies the alterations of this archetype as it has reached other Islamic lands. Reconstructing old buildings into mosques, or taking the examples of other structures in building mosques, the geometry of every domestic architecture was incorporated into mosques of each land. This added new elements to mosques making them distinguished and unique, just like the first mosque. Afterwards, by studying some of the oldest mosques in Iran and the Persian mosque’s origins, the frequency of use of shabestan, chahartaghi and eivan in the maps of initial mosques have been shown. Then, the process of emergence of these mosques and their results, have been geometrically studied. These initial experiences generated the genesis of three geometric fundamental types of mosques in the following centuries, which have been categorized and analyzed along with samples. As a result, two different consequences have been described. One was the continuity of construction in these three types; the other was the convergence of them. This convergence was a new process in a new architectural function, so it was only possible through experiment. Therefore, some of shabestan-based mosques were changed into workplaces for this experiment, some of them lasting several centuries. After that, some new mosques were built with domed four-eivan geometry. Finally, the geometrical process of Isfahan’s Grand Mosque and its resultant on the basis of its court and its old shabestan has been analyzed. This mosque is one of the first workplaces of the convergence of these three basic types. The construction of shabestan, the gonbad-khaneh (dome chamber) in it, and the eivan in the court, are the chronological process of evolution of the mosque. Evidences show that convergence and adaptation of the three fundamental geometric types in this mosque lasted three centuries to result in the geometry of the Persian mosque.