LEWISTON — On Sunday morning, the clock on the Bates College campus in Lewiston rang in a new beginning for about 475 graduates, and senior class speaker, Rakiya Mohamed of Auburn, referred to herself and her fellow classmates as “certified world changers.”

Of the class, in which one in nine students was the first in his or her family to go to college, President Clayton Spencer observed that “every seat, every tree (was) taken” in celebration of the students who were urged by their chosen speaker to “challenge neutrality” and “transform (their) intellect.”

Mohamed, who majored in biological chemistry and African-American studies, told the class of 2018 she had always known she wanted to attend Bates because that was the path most likely to prepare her to make the big changes she wanted to see in the world.

She spoke of her strong ambitions, which wavered slightly as she realized the magnitude of the changes she was hoping to make and the seemingly endless list of problems the world faces.

“By the end of my first year (at Bates) … discouragement seeped into my mind, and I was faced with a really hard truth — we live in a pretty messed up world,” Mohamed said.

Thanks, however, to the people she met along her educational journey, she was refreshed and motivated.

“I was encouraged to be unapologetic and bold with my voice,” Mohamed said. “I relearned what it means to be a black woman.”

She referred to culture as “a fluid and ever-changing social structure” that should be constantly challenged and told the graduates to “divide and conquer” and “keep being the change (they) wish to see in the world.”

“We have taken it upon ourselves to make sure we change for the better, and I take immense pride in that,” Mohamed said.

Four honorary degrees were conferred during the ceremony, to photojournalist Lynsey Addario, author and scholar Jill Lepore, musical genius Robert Ludwig and Bryan Stevenson, founder and executive director of the Equal Justice Initiative in Alabama.

Stevenson delivered a passionate commencement address, in which he tasked the graduates with four “very important” missions: seek proximity to people suffering, change the narratives under the issues, stay hopeful and be willing to do uncomfortable and inconvenient things.

“Hope is your superpower,” he told the new graduates. “You have an obligation to use what you’ve learned to change things. That degree you’re going to receive doesn’t just speak to the past. It’s an invitation to look to the future.”

Even within the dialogue on the world’s problems and the need for change, Mohamed and Stevenson reminded listeners to focus on what can and must be done to, as Stevenson said, “allow the ideas of (their) minds to be fueled by the convictions in (their) hearts.”

“We are equipped with the skills that can make this world a better place, of that I’m sure,” Mohamed said.

“As I think of the issues we face today and I go back to that list of the world’s problems, I’m not as overwhelmed as I once was. Now I’m anxious, I’m excited, but most important, I feel prepared.”