It's a safe bet that a lecture combining free-market economics, gender and wage gaps will generate attention on an average college campus. Add race and IQ to the equation, and it's all but certain to explode in controversy.

And that's what happened when Walter Block, an economics professor at Loyola University New Orleans, a Jesuit institution, gave a talk this month, "Injustices in the Politics and Economics of Social Justice," at Loyola College in Maryland, a fellow Jesuit institution.

By his own account, Block discussed the gap in wages between males and females and explained it as mainly a side effect of the "asymmetric effects of marriage." In an explanatory post written at a Web site devoted to the "Austrian school" of libertarian thought, Block wrote: "This institution enhances male earnings and reduces those of females. Why? Because wives do the lion’s share of cooking, cleaning, shopping, child care."

He then continued on to a discussion of men's and women's productivity, arguing that males were more likely to be at either extreme of achievement while females tended toward the middle.

It was only in the question-and-answer session, he said, that someone asked him about the wage disparity between whites and blacks. In his response, although he "was very careful to say that the cause was a matter of dispute," Block said the "politically correct answer is that lower black productivity is due to slavery, Jim Crow legislation, poor treatment of African Americans in terms of schooling, etc. The politically incorrect explanation was supplied by Richard Herrnstein and Charles Murray in their book The Bell Curve: lower black IQs."

While Block said there was no major stir at the time, by the weekend Loyola College of Maryland's president, the Rev. Brian F. Linnane, had sent an e-mail to students referencing the lecture.

"Many in attendance found some of Professor Block's comments both insensitive and incorrect, and have shared their concerns with members of the economics department and others throughout the college," Father Linnane wrote.

"While economics faculty members have issued a response and apology, I feel it is important at this time to remind all members of the Loyola community that while our commitment to academic freedom ensures that we welcome students, faculty and guest speakers of all academic and political perspectives, we will not endorse or support racism, sexism or any other form of intolerance.

"We are a Jesuit institution, and as such, a respect for diversity is one of our defining values, and an essential component in our commitment to preparing men and women to become leaders in a rapidly changing world made all the more rich by the many cultures and viewpoints that shape it."

Perhaps almost as notable as the president's direct response was the condemnation issued jointly by the college's economics department and the Adam Smith Society student group, which is named for the 18th-century free-market economist. In an unsigned letter to the student newspaper, members of the department wrote, "It is important to note that the remark was offensive not just because it was racially insensitive, but because it was erroneous and indicated poor-quality scholarship. There is ample scholarly evidence that, after adjusting for productivity-related characteristics (e.g., years of schooling, work experience, union and industry status, etc.) a considerable wage gap remains."

Block, who is also a senior fellow at the Austrian-oriented Ludwig von Mises Institute, said in an interview that Smith would be "spinning in his grave," and that he may include the incident in a book he is writing on racial and sexual discrimination, to be published by the Institute.

At least at his home institution in New Orleans, he said, there was no resistance from faculty. "The only people I'm getting in trouble with so far are the politically correct thought police at Maryland," he noted, adding that he was willing to debate members of the Loyola College faculty on the issues.

It wasn't the discussion on gender and wages that sparked the outcry, Block noted -- only the mention of race and IQ at the end, what he called "the third rail of American academia."

"Just mentioning the word 'IQ,' it's as if you use the F word in polite society," he remarked.

"Loyola's core values include a commitment to integrity and honesty, where freedom of thought and expression are valued and protected," said Courtney Jolley, director of public relations at the Baltimore institution.

"The college supports this by striving to foster respect for others and their work, and supporting a sharing of varied opinions which helps students refine their own ideas. But there is a difference between freedom of speech and freedom from criticism. Loyola encourages the continued exercise of freedom of speech as an example of academic discourse, and the college has not apologized for having Dr. Block on campus to speak. But, Loyola community members have the right to comment on differences between their beliefs and positions and statements made by those who speak on campus."