Massachusetts Hall in Harvard Yard can be an awfully stuffy place. Self-important college administrators are used to being treated respectfully, if not reverently. At least that was the case until Lawrence “Larry” Summers took over the hall as the 27th president of Harvard University on July 1, 2001. Then everything changed. If Massachusetts Hall had been a tidy “china shop”, it got its raging bull.

From the beginning of his term, Summers has often ruffled feathers, including my own, with his controversial talks, many of them off-the-cuff. But six weeks ago he broke an absolute academic taboo by discussing “issues of intrinsic aptitude” and “variability” based on gender.

He suggested that among the explanations — certainly not the justifications — for the relatively small number of women on the maths and engineering faculties of the most elite research universities might be “different availability of aptitude at the high end”.

Summers made it clear he “would far prefer to believe something else” and that he “would like nothing better than to be proved wrong”, because “it would be easier to address what is surely a serious social problem if something else were true”. He offered his theory, as one of many, in order to “provoke” his audience of high-powered academics.

He succeeded beyond all expectations, provoking a firestorm of criticism, condemnation and outrage that threatened not only his presidency but, even more importantly, academic freedom to provoke controversy about the taboo subject of gender and aptitude.

The immediate response to Summers’s provocation was a manifestation of one of the oldest and most damaging sexist stereotypes. Professor Nancy Hopkins of the Massachusetts Institute of Technology, instead of arguing with Summers, acted like a character out of a 19th-century novel.

This is how she described her reaction to what Summers said: “My heart was pounding and my breath was shallow. I just couldn’t breathe because this kind of bias makes me physically ill.” She said that if she hadn’t walked out she “would’ve either blacked out or thrown up”. As Margaret Carlson, a feminist who writes for the Los Angeles Times, put it: “For goodness sake — a return of the vapours. That’s not going to get us to the top.”

Neither will trying to prevent all discussion about possible gender differences. After the story of the Summers speech was leaked to the press by Hopkins — the discussion was supposed to be off the record — the censors went to work. Instead of responding to what they regarded as “bad science” with better science, they condemned Summers for even raising the issue of possible differences in particular aptitudes based on gender. They focused on his position as president of a university, insisting that, in this role, he has to be careful about not offending any of his constituents.

The problem is that if a university president were to be fired because he expressed the views put forward by Summers, it would become only a matter of time before professors, researchers and students would also be subjected to discipline for expressing similar views.

Once a point of view becomes an impermissible one on a university campus, nobody can express it without fear of recrimination. Dismissing a president on such grounds would give an imprimatur of legitimacy to censorship of the views that formed the basis for his dismissal.

That is why this issue is bigger than Summers or even Harvard University. It is really about a long-term, systematic effort to impose a political-correctness straitjacket on certain views, especially at universities.

It began with the enactment of speech codes, harassment policies and other disciplinary mechanisms designed to censor speech deemed offensive to some. The Summers presidency has stood in stark contrast to political correctness. He has refused to subscribe to the first commandment for university presidents: make only speeches that risk offending nobody.

Because Summers has repeatedly broken this commandment, Harvard has become the most exciting, diverse, intellectually stimulating and, yes, provocative university in the world. If Summers now begins to “temper words”, as he told the faculty of arts and sciences he would do, Harvard will become a less interesting place.