Dr. Summers's remarks, which have only been described by others until now, have fueled a widening crisis on campus, with several professors talking about taking a vote of no confidence on the president next week. That idea alone is unprecedented at Harvard in modern times.
Among his comments to a conference of economists last month, according to the transcript, Dr. Summers, a former secretary of the United States Treasury, compared the relatively low number of women in the sciences to the numbers of Catholics in investment banking, whites in the National Basketball Association and Jews in farming.
He theorized that a "much higher fraction of married men" than married women were willing to work 80-hour weeks to attain "high powered" jobs. He said racial and sex discrimination needed to be "absolutely, vigorously" combated, yet he argued that bias could not entirely explain the lack of diversity in the sciences. At that point, the Harvard leader suggested he believed that the innate aptitude of women was a factor behind their low numbers in the sciences and engineering.
"My best guess, to provoke you, of what's behind all of this is that the largest phenomenon - by far - is the general clash between people's legitimate family desires and employers' current desire for high power and high intensity; that in the special case of science and engineering, there are issues of intrinsic aptitude, and particularly of the variability of aptitude; and that those considerations are reinforced by what are in fact lesser factors involving socialization and continuing discrimination," Dr. Summers said, according to the transcript.
"I would like nothing better than to be proved wrong, because I would like nothing better than for these problems to be addressable simply by everybody understanding what they are, and working very hard to address them," he added.
Over and over in the transcript, he made clear that he might be wrong in his theories, and he challenged researchers to study his propositions.
He also urged research on "the quality of marginal hires" to the faculty when efforts to diversify are under way. How many of these hires, he asked, have "turned out to be much better than the institutional norm who wouldn't have been found without a greater search?" Or are "plausible compromises" that are not unreasonable additions to the faculty? And "how many of them are what the right-wing critics of all of this suppose represent clear abandonments of quality standards"?
Several Harvard professors said they were more furious after reading the precise remarks, saying they felt he believed women were intellectually inferior to men.
Everett I. Mendelsohn, a professor of the history of science, said that once he read the transcript, he understood why Dr. Summers "might have wanted to keep it a secret."
"Where he seems to be off the mark particularly is in his sweeping claims that women don't have the ability to do well in high-powered jobs," said Professor Mendelsohn, part of a faculty group that sharply criticized Dr. Summers's leadership at a meeting of the Faculty of Arts and Sciences on Tuesday. "There's an implication that they've taken themselves out of that role. But he brings forward no evidence."
Howard Georgi, a physics professor who has been part of a successful effort in his department to recruit women for tenured positions, said, "It's crazy to think that it's an innate difference." He added: "It's socialization. We've trained young women to be average. We've trained young men to be adventurous."