At 4pm on a February afternoon this year, 200 professors from the faculty of arts and sciences at Harvard University filed into the 190-year-old University Hall in the middle of Harvard Yard and settled down on the plastic folding chairs beneath the oil paintings and chandeliers. It was supposed to be a regular meeting of the teaching faculty. But some of the academics were about to launch what one of them would later describe as a "surprise attack" on Larry Summers, Harvard president.

Twelve months earlier, Summers, leader since October 2001 of America's oldest university, had survived a tumultuous no- confidence vote by the professors after suggesting in an off-the- record speech that "intrinsic" physiological differences might be a big reason why there were more men than women in top jobs in science and engineering. The unrest had died down but today, suddenly, as the afternoon turned to dusk, he faced new criticisms about his abrasive management style and his personal links to an economics professor at the centre of a fraud scandal.