The Eureka effect’s emotional impact regarding the elegance of structural reciprocity was the inheritance that Gaudi, Torroja, Candela, and finally, Calatrava shared.

The Nubian arch and vault embodied the artist’s ideal, what they strive for, that aha moment when the seen and unseen merge to form a new understanding of the whole, a gestalt.

They observed a gestalt composed of a spatial system without structural hierarchy.

Since the keystone did not exist at the top of the Nubian arch, each brick was placed at the precise location with the exact amount of friction to create a slight slope capable of forming a self-supporting vault, which was essential in the inverted catenary curve.

The form unconsciously entrained them with its simplicity and ability to withstand the weight of the material from which it is constructed without collapsing.


Carried along in the Flow, the form suggested a constructivist learning approach where concentration, reflection, and meditation altered their awareness. They were not building a style but a physical picture of their mental state while envisioning reciprocal cooperation.

The “over-arching” form symbolized reciprocity and acted as an external visual stimulus leading to brainwave activity oscillating at the same frequency––what constructivist learning theory considers most important, “learning exists in the mind.” Still, they did not know this; they felt it and responded accordingly in their art.