In his Class Day speech on Wednesday (June 6) Bill Clinton remarked that the great lesson he learned from the human genome project, which was brought to completion during his presidency, is that genetically all humans are 99.9 percent identical.

It’s too bad, he remarked, that we spend much more time thinking about the .1 percent that divides us than the 99.9 percent that we have in common, because that imbalance keeps us from making positive changes in the world.

“There is no challenge we face — no barrier to having our grandchildren here 50 years from now — that is greater than the ideological and emotional divide that continues to demean our common life and our ability to solve our common problems.”

Clinton’s inspiring address was the culmination of a ceremony held in weather so deliciously springlike that even sitting for two hours on hard, undersized folding chairs could not dampen the spirits of the huge Class Day crowd.

Class Day is traditionally a day of fun and celebration dedicated to and run by the students themselves. Class Day speakers, who are chosen by the graduating class, have run the gamut from Mother Teresa to Sacha Baron Cohen alias Ali G, alias Borat. Reflecting on the varied nature of his predecessors, Clinton wondered about his own selection.

“I couldn’t figure out why, on a day that’s supposed to be an occasion of fun and celebration, you would pick a gray-haired 60-year-old to speak.”

But rather than comparing himself with the many comedians who have brought laughter to past Class Days, Clinton decided to focus on the noncomedians and the graduating classes who chose them.

The list begins with Martin Luther King Jr., who was chosen by the Class of 1968 but was killed in April of that year. His widow Coretta Scott King delivered the speech in his stead. Others who delivered a more serious message were Bono and of course Mother Teresa. Clinton also mentioned Nelson Mandela, who was not a Class Day speaker but was given a special honorary degree by Harvard in 1998.

“I believe that Martin Luther King, Mother Teresa, and Bono were asked here by people who believe that our common humanity is more important than our differences,” Clinton said.

Although there are terrible problems in the world, ordinary people have more opportunities to engage in active service and to create change than ever before because of the enormous growth of NGOs and the ability of the Internet to unite people, Clinton said. He praised his former political rival, 82-year-old George H.W. Bush, for engaging with Clinton in numerous efforts to bring relief to victims of the 2004 tsunami and other disasters.

“I love the guy. I’m sorry for all the die-hard Democrats in the audience, but I do.”

Clinton cautioned the graduates that the great temptation as they fill the leadership positions for which their Harvard education has prepared them is “to believe that the .1 percent that makes you different is the sum of who you are and that you deserve your good fortune.”

Instead, he urged them to “be true to the traditions of the great people who have come here and think about the other 99.9 percent … Enjoy your good fortune, enjoy your differences, but realize that your common humanity matters much, much more.”

Class Day also featured orations by members of the Class of 2007, some of whom tried to distill philosophic lessons from their four years at Harvard, while others strove, and succeeded, in getting a laugh.

Joshua Patashnik spoke about Harvard’s ability to engender humility in its students, which, he said, is probably a good thing.

“We need more people willing to admit that their political opponents are sometimes right. We need fewer people unyieldingly convinced that their religious beliefs or lack thereof constitute the only acceptable incarnation of absolute truth.”

Rachel Nolan discussed leadership and followership. She has chosen to be a follower, she said, because she calculates that just in the last 20 years, “Harvard has produced significantly more leaders than the world can handle.”

Looking toward a career as a journalist, she plans to be a curious and truth-seeking follower, however, which she sees as important virtues.

“Each and every one of you will be a follower in some aspect of your life; make sure that you research well and follow carefully.”

Tracy Nowski delivered the first Ivy Oration, in which she mused humorously on her expectations of Harvard and whether or not they have been fulfilled.

“I expected — like many of you, I’m sure — that being at Harvard would make me smarter; otherwise, this is the most expensive four-year slumber party I’ve ever been to.”

The second Ivy orator, Kiernan Schmitt, spoke about his lifelong love affair with Harvard, and his parents’ fears that he might not be able to get in.

“I remember their concerned whispered exchanges, peppered with phrases like ‘10 percent admissions rate,’ and ‘high SAT requirements.’”

Also on the program was the announcement of the Ames Awards for “selfless, heroic, and inspiring leadership.” They went to Rajan Sonik and Rabia Mir.

Eleven elevated to officer