Microsoft founder Bill Gates returned to Harvard Thursday (June 7) to finally collect his degree — an honorary doctorate — and to urge the Class of 2007 to change the world for the millions who live in poverty and die of preventable diseases each year.

The world’s problems may seem intractable, Gates said, but with the advances in technology and the resources at the disposal of today’s graduates, they have never been more solvable.

Gates quoted his mother, saying, “From those to whom much is given, much is expected,” and added that the world has enormous expectations of those from Harvard.

“When you consider what those of us here in this Yard have been given — in talent, privilege, and opportunity — there is almost no limit to what the world has a right to expect from us,” Gates said. “Be activists. Take on the big inequities. It will be one of the great experiences of your lives.”

Gates was the Commencement Day speaker during the annual meeting of the Harvard Alumni Association in Harvard’s Tercentenary Theatre. Commencement exercises at Harvard consist of two main parts. Degrees are conferred on the year’s graduates during Morning Exercises in Tercentenary Theatre, the area between the Memorial Church and Widener Library. This year, more than 6,000 graduates of Harvard College and Harvard’s graduate schools joined the ranks of 330,000 alumni in 185 countries around the world, according to Alumni Association President Paul J. Finnegan.

The Afternoon Exercises consist of the annual meeting of the Harvard Alumni Association, which included both the day’s graduates and alumni from years past. It is during the annual meeting of the Harvard Alumni Association that the Commencement speaker delivers his or her address.

Harvard interim President Derek Bok also addressed the afternoon assembly. Just weeks before his successor, Drew G. Faust, takes office on July 1, Bok presented what he sees as challenges facing higher education generally and Harvard specifically.

Like Gates, Bok sees opportunity facing today’s Harvard. Bok said that in today’s information age the University — and other universities around the world — play more important roles than ever. Demand for the services of higher education are growing, he said, and therein lies the challenge. How do universities meet that demand? Who do they educate and how? How do they measure and improve that education? And, with the knowledge generated at universities at a premium, what services beyond education — such as consulting for government and market reform — should they provide?

Bok said enormous opportunities lie in the sciences, with technology fueling discoveries in genomics, neuroscience, and a host of other areas. Universities of the future will have to decide how best to take advantage of the scientific opportunities that present themselves.

In addition, Bok said, universities have to figure out how to encourage robust growth in the humanities. While some may think there’s a danger that the humanities will wither in the shadow of science’s growth, Bok said the societal and cultural changes and the ethical dilemmas posed by scientific advances can only be answered by the humanities.

“The traditional focus of the humanities on questions of value, meaning, ethics are more important than ever before,” Bok said. “Far from marginalizing the humanities, universities must look for ways to encourage humanists to address such questions in ways we can all understand so they can help us build a world where our scientific advances don’t overwhelm us, but are made to serve humane purposes,” he said.

Bok said one must look back to the period after the Civil War to find a time of such opportunity for Harvard.

“This is a much more formidable agenda than I have seen in my lifetime. It is also more significant,” Bok said. “Universities matter more to society today than ever before. Harvard is especially important, since we now possess the greatest collection of exceptional students, talented faculty, and financial resources of any university on Earth. Deciding how to use those remarkable talents for the greatest good is an awesome responsibility of vital interest to everyone.”

Gates, who spoke after Bok, reflected on his own Harvard experience. Though he dropped out to start Microsoft, Gates said Harvard was a “phenomenal experience” for him. The knowledge he gained and the people he met at Harvard proved immensely important in his life.

“It could be exhilarating, intimidating, sometimes even discouraging, but always challenging,” Gates said. “It was an amazing privilege — and though I left early, I was transformed by my years at Harvard, the friendships I made, and the ideas I worked on.”

Gates said one thing he did not learn at Harvard, however, was about the world’s inequities. He said he was shocked to learn that millions of children die each year of diseases that are absent from the industrialized world and that could be treated if the will was there.

After analyzing the problem, Gates said, he figured out the cruel reason that nothing had been done.

“The answer is simple and hard. The market did not reward saving the lives of these children, and governments did not subsidize it. So the children died because their mothers and fathers had no power in the market and no voice in the system,” Gates said. “But you and I have both.”

Gates urged graduates and others in the audience to work to create market forces that provide incentives — profits for businesses and votes for politicians — to help the world’s poorest and least fortunate.

Gates said he believes that the biggest barrier to solving the problems of inequity is not a lack of caring, as some believe, but that finding ways to contribute are too complex. Many people, he said, would help if they only knew how.

To do that, he said, requires determining a goal, finding the highest-impact approach, discovering the ideal technology for that approach, and continuing to do what works best now while those other things are going on. And above all, he said, don’t get discouraged.

“The crucial thing is to never stop thinking and working — and never do what we did with malaria and tuberculosis in the 20th century — which was to surrender to complexity and quit,” Gates said. “In line with the promise of this age, I want to exhort each of the graduates here to take on an issue — a complex problem, a deep inequity, and become a specialist on it…. You have more than we had. You must start sooner and carry on longer.”

Barbara J. McNeil named acting dean of Harvard Medical School