The double meanings inherent in the phenomenon both-and can involve metamorphosis as well as contradiction. I have described how the omni-directional spire of the tower of Christ Church, Spitalfields, evolves into a directional pavilion at its base, but a perceptual rather than a formal kind of change in meaning is possible. In equivocal relationships one contradictory meaning usually dominates another, but in complex compositions the relationship is not always constant. This is especially true as the observer moves through or around a building, and by extension through a city: at one moment one meaning can be perceived as dominant; at another moment a different meaning seems paramount.