"... the rectangle is something very basic to us. The Vedics .. .knew the Earth was round, but they represented it as a square. So when you go into a five-sided room for the first time it's exciting, but if you do it repeatedly you destroy the surprise"

This is not just a practical matter, but to do with the ways that buildings carry meanings ("the wellspring of the imagination comes from climate"). "A great example is the Pantheon in Rome, just stunning, so brilliant", where a large circular hole is placed at the top of the dome, which lets out smoke and lets in a thick shaft of sunlight. It's not something you would do somewhere wetter or colder, but here it also represents "the axis mundi, the sky hitting the Earth – there are so many layers".

Correa was ahead of his time in other ways. His Hindustan-Lever pavilion, for the 1961 international trade fair in Delhi, was a multifaceted structure resembling a piece of crumpled paper that seems to foreshadow the work of Frank Gehry. It wasn't a line he pursued further, however, and after making due recognition that Gehry is not just about funny shapes, he explains: "We understand space in four directions, and the rectangle is something very basic to us. The Vedics, for example, knew that the Earth was round, but they represented it as a square. So when you go into a five-sided room for the first time it's exciting, but if you do it repeatedly you destroy the surprise. The more you change things, the more they stay the same."

Charles Correa in conversation, Rowan Moore in The Observer, Sunday 12 May 2013