Gothic architecture is not merely about ornamentation. The Gothic style brought innovative new construction techniques that allowed churches and other buildings to reach great heights.
One important innovation was the experimental use of pointed arches. The structural device was not new. Early pointed arches can be found in Syria and Mesopotamia, so Western builders probably stole the idea from Moslem structures. Earlier Romanesque churches had pointed arches, too, but builders didn't capitalize on the shape.
The Point of Pointed Arches
During the Gothic era, builders discovered that pointed arches would give structures amazing strength and stability. They experimented with varying steepness, and "experience had shown them that pointed arches thrust out less than circular arches," says famed architect and engineer Mario Salvadori. "The main difference between Romanesque and Gothic arches lies in the pointed shape of the latter, which, besides introducing a new aesthetic dimension, has the important consequence of reducing the arch thrusts by as much as fifty percent."
In Gothic buildings, the weight of the roof was supported by the arches rather than the walls. This meant that walls could be thinner.
SOURCE: Why Buildings Stand Up by Mario Salvadori, McGraw-Hill, 1980, p. 213.