‘Architecture’, declared Kahn, ‘is the thoughtful making of spaces.’ His work contains many examples of indoor and outdoor rooms conducive to meditation. One thinks for example of the Salk Institute in La Jolla, California (1965) which uses an open space to address the horizon line of the Pacific, and which employs a channel of water and light to suggest a metaphysical dimension in the research into the hidden laws of nature. Or again, one thinks of the Kimbell Museum in Fort Worth, Texas (1972) with its cycloid vaults split open at their crest to admit a crack of daylight to the interiors where it is diffused over polished concrete surfaces. In these late works, Kahn seems preoccupied with making the immaterial visible through the most elemental means. Structure, space and light are fused.