Repetition takes place in time and space. But the same may be said of everything aesthetic, architectural or otherwise. Which of these has priority, then? Time or space? Empirically, the recognition of repeated instances is almost always a temporal affair. They take a little while to figure out, in other words. Some disagreement remains as to whether this procedure is more a function of memory or perception, however. In studies of repetition blindness, for example, it is unclear if the failure to recognize recurring items in a sequence owes primarily to one’s inability to notice similarities the second time something appears. Conflicting evidence indicates it could just as easily involve an inability to remember the qualities it displayed the first time around. Psychologists are still split over this question.
Repetition has been acknowledged as an important aspect of architecture and design for several centuries now, although it was seldom theorized until recently. Despite architecture’s usual preoccupation with problems of space, most repeating patterns or spatial arrangements require time to grasp. That is, unless they’re intuited all at once, in a single glance. One must first be allowed to perambulate the structure, eyes gliding along its surface. György Kepes, a Hungarian painter closely associated with his fellow countryman, the Bauhaus master László Moholy-Nagy, therefore asserted in his Language of Vision (1944):
The orderly repetition or regular alternation of optical similarities or equalities dictates the rhythm of the plastic organization. In recognizing such order one learns when the next eye action is due and what particular neuromuscular adjustment will be necessary to grasp the next unit. To conserve the attentive energies of vision, therefore, the picture surface must have a temporal structure of organization — it must be rhythmically articulated in a way that corresponds, for the eye, to the rhythm of any work process.
Kepes may have had visual media in mind when he wrote these lines about “the picture surface,” but the observation holds good for architecture as well. For the prolific Danish urbanist and critic Steen Eiler Rasmussen, serial repetition offered a quintessential means by which to convey orderliness in design. “The simplest method,” wrote Rasmussen in his 1959 guide Experiencing Architecture, “for both the architect and the artisans, is the absolutely regular repetition of the same elements, for example solid, void, solid, void, just as you count one, two, one, two. It is a rhythm everyone can grasp.” Once again, as it had been for Kepes, repeated components operate by establishing a kind of rhythm of intuition, which then structures all subsequent experience. Each passage highlights the peculiar double-aspect of repetition in architecture: it is simultaneously an objective property of the built work — perceptible to both inhabitants and passersby alike — as well as a subjective approach to design.
 In the sense meant by Kant, who held that all phenomena appear in space and time: “[T]here are two pure forms of sensible intuition as principles of a priori cognition, namely space and time.” Kant, Immanuel. Critique of Pure Reason. Translated by Paul Guyer and Alan Woods. (Cambridge University Press. New York, NY: 1998). Pgs. 157, 174.
 Fagot, Clark and Pashler, Harold. “Repetition Blindness: Perception or Memory Failure?” Journal of Experimental Psychology: Human Perception and Performance. (Vol. 21, № 2: April 1995). Pgs. 275-292.
 Kepes, György. Language of Vision. (Dover Publications, Inc. Mineola, NY: 1995). Pg. 53.
 Rasmussen, Steen Eiler. Experiencing Architecture. (The MIT Press. Cambridge, MA: 1964). Pg. 129.