University President Lawrence H. Summers addressed members of the Summer School on Wednesday, welcoming them with a discussion of challenges posed by a changing world order and rapid technological advance.

University President Lawrence H. Summers welcomed summer school students to Harvard on Wednesday, telling them that America must embrace new twenty-first century challenges and work to turn potential stumbling blocks into opportunities for development.

Summers, speaking in the Science Center, told a packed crowd that the rise of Asian economies and revolutionary changes in the life and medical sciences are two of the most important transformations occurring today.

He said that wise leadership is necessary to ensure that Americans assess the challenges of progress realistically and deal with them effectively, all while retaining fundamental American freedoms.

“The potential risks to humanity are far greater than they have been historically,” Summers said. “The other thing that could be in those history books is the tragic errors that we could make that could lead to global conflict, to global cataclysm.”

He stressed the role of the University within the new framework, arguing that Harvard should help provide the necessary leadership—in the form of “new thought that can apply old values in a new context created in a changing world.”

He warned that the U.S. should not look at developments “naively” and must recognize economic threats as they arise. But he did encourage America to embrace the birth of strong economies in Asia.

“The right posture for us is to welcome it and see it as bringing economic benefits for the U.S., Asia, and the world,” he said.

Summers said that, as only the seventh president of Harvard since 1865, he tries to carry on his position’s mandate to confront issues from a long-term, historical perspective.

Questions about American foreign policy took the bulk of the question-and-answer session that followed Summers’ remarks, although the students also addressed other topics—including Harvard’s place in the public eye and Summers’ controversial January remarks that “issues of intrinsic aptitude” may be responsible for a dearth of women scientists. Those comments sparked strong criticism from many professors and culminated in a March vote of no confidence in Summers’ leadership.

Answering a question about Harvard’s portrayal in the entertainment media, Summers said that much of what happens on campus comes under intense scrutiny from those outside its gates.

“That fact that when people think of a university the first they think of Harvard is something we can be very proud of,” he said. “We have a tremendous bully pulpit where what’s done at Harvard is watched.”

When asked whether he thought political correctness could hinder freedom of speech, the president paused and shook his head.

“My hope is that universities could be places where any idea could be put forward,” he said. “Any idea should be open to criticism, attack, and refutation.”

“We all have a tremendous obligation to speak and act in ways that welcome everybody into our communities,” he said, adding that Harvard should be open to both provocative ideas and criticism of those ideas.

Summers addressed the topic of women in science directly, saying that Harvard must strive to make all career paths open to everyone.

“At the same time,” he said, “I think there are some important questions that need to be openly discussed. Why do we observe the patterns we observe? Why do we make the choices that we make?”

Summers imparted to the students a lesson he has learned as president.

“When I left Washington, I didn’t leave politics entirely behind,” he said.

His apparent candor throughout his remarks struck some students in attendance.

“I was actually extremely impressed with how honestly he seemed to respond to the questions,” rising high school junior Everett Wallace said. “Before this, it seemed like his words would have such a huge political impact that he couldn’t say anything.”

Summers drew a few laughs with quips woven through his remarks.

He waved off an introduction by Summer School Dean Robert A. Lue with a self-deprecating joke about economists. When widespread laughter did not ensue, Summers waited for a few seconds before adding, “Think about that for a minute.”

—Staff writer Samuel C. Scott can be reached at sscott@fas.harvard.edu.