Harvard University President Lawrence H. Summers made a big mistake: He was honest. He reportedly had the temerity to suggest at a conference in Cambridge that innate difference between genders may play a role in the underrepresentation of women among top scientists.

The crowd of academics was shocked by this momentary deviation from politically correct dogma. The Washington Post quoted a distraught Nancy Hopkins, biology professor at the Massachusetts Institute of Technology: “I felt I was going to be sick. My heart was pounding and my breath shallow. I was extremely upset.” Setting aside Ms. Hopkins’ overreaction — an embarrassing caricature of delicate female sensibilities — what exactly is so threatening about the possibility that men and women have different intellectual preferences and abilities?

Leaders of the organized feminist movement see such ideas as an excuse for discrimination or for discouraging women from pursuing science. Yet once again, the gender warriors are confusing equality of opportunity with equality of outcome.

Mr. Summers, in the spirit of scientific inquiry, was exploring potential explanations for an observable fact: that women on average are less likely to reach the upper echelons of science than are men. He has not questioned whether individual women can excel in these disciplines.

Nor is anyone arguing that women should be blocked from studying or conducting science. The principle of “equal opportunity for all” is universally accepted in America. It’s possible, though, that women may have the same opportunities but less interest in some fields than men. This upsets the hard-core feminists, who want a world where women and men fill quota-like 50-50 percentages in all walks of life. It’s this obsession with equal outcomes that induces palpitations and the vapors when the president of America’s most solidly liberal university merely voices a stray thought.

The constant grumbling about the “wage gap” — the difference between the median wage of women and men — is another product of this obsession. If the gap were caused by systemic discrimination, the feminists would have a point. The reality, however, is that differences in wages reflect legitimate choices about where and how much to work. Compare a man and a woman in the same field with the same experience and education, and the gap shrinks rapidly.

We know individuals make different tradeoffs in their jobs: Some seek solely to maximize earnings, while others opt for less pay and greater personal fulfillment or flexibility. On average, women have tended to value greater flexibility, shorter schedules and more time with family. As long as men and women have different preferences, there’s going to be a statistical “wage gap.”

Title IX is another example of the feminist fixation on outcomes. This federal law was intended to prevent gender discrimination on college campuses, including in athletics. It has evolved into an outcome-driven policy in which litigation-fearing colleges strive to make athletic rosters “proportional” to enrollment. Since women account for more than 50 percent of undergraduates, women are supposed to account for more than half of all college athletes.

Cutting sports for men is the easiest way to achieve parity, since women on average are less interested in athletics. Since the 2000 Olympics, more than 90 universities have eliminated track and field for men, and more than 20 have canceled wrestling.

“Women’s rights” once meant choices for women. No longer. Now feminists want to do the choosing for everyone, and woe to anyone who questions the outcomes they deem virtuous. It’s a sad commentary on the leaders of a movement that once was devoted to freedom.