And still do. Go and see the photos, drawings and models of Mies houses of the 1920s and early 1930s, and you see exactly what inspires the current generation of young architects - those, that is, who have not been seduced by the now waning fashion for meaningless curves and blobs. As the right angle returns to favour, so does Mies - though note that even he abandoned the corner entirely in his glass skyscraper proposal of 1922, which is like a rippling Alvar Aalto vase. But Aalto didn't design that famous vase until 1936, so Mies was well ahead of the game. Of course the skyscraper design was unworkable - the floors were the wrong shape and too small - but it shows well the early Expressionist side of Mies.

Later, he was to reject this. "I don't want to be interesting," he said. "I want to be good". You can see why his star was eclipsed for a while in the sensation-seeking, interesting-shapes architectural period of the late 1990s and early 2000s. The Bilbao Guggenheim by Frank Gehry is the exact opposite of everything Mies stood for. Though just because it is interesting, does not necessarily mean that it is NOT good. Any more than a Mies building has to be boring, just because it IS good. However, when the American postmodernist Robert Venturi offered the aphorism "Less is a bore" in response to the cult of Mies, it ushered in a rival cult of pre-Guggenheim 1980s architectural excess that quickly palled. *

In contrast Mies, though he might not have wanted to be interesting, was at his best capable of producing architecture of timeless beauty. It's what you take away from the Whitechapel: a Platonic notion of universal beauty finding form in one man's buildings. Of course the Third Reich could not live with that. But why was Mies so slow to admit it?

Mies van der Rohe 1905-1938, Whitechapel Art Gallery until 2 March 2003. www.whitechapel.org