Thousands of graduating UCLA students bursting with four years’ worth of hard-earned knowledge were reminded by speakers to remain open to challenging ideas, and to prevent ideology from calcifying their opinions.

Before Friday’s UCLA College commencement, the campus filled with festive families and friends, carrying balloon bouquets and flower leis, holding the hands of small children or the leashes of small dogs, walking in groups or rolling singly on motorized scooters and skateboards.

Graduation season at UCLA includes nearly 60 ceremonies, receptions and celebrations across campus, the bulk of them taking place Friday or this weekend. The two undergraduate commencements inside UCLA’s historic Pauley Pavilion are the largest events, where roughly 20,000 guests saw more than 5,800 students earn their diplomas. UCLA is awarding about 4,700 graduate and 8,300 undergraduate degrees this academic year to a diverse array of students. Roughly a third of UCLA undergraduates are the first in their family to attend college, and more than a third come from low-income families.

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They’ve seen the world change in significant ways over the past four years, said graduating neuroscience major Gauri Ganesh as she waited with friends to march into Pauley.

“The political climate of America has changed,” Ganesh said. “Here, we’ve been exposed to all different types of viewpoints. I might not have known how fast the world was changing if I weren’t in a college environment with so many different perspectives.”

The graduates heard speeches that touched on the turbulent social issues that colored their college years. Chancellor Gene Block congratulated them on being the best UCLA class yet, and answered questions that students had sent in advance about how to approach uncertainty, how make the world better, and how to connect with community. The answers lie in remaining open to different ideas, even when they are challenging or upsetting, Block said.

“I was really deeply impressed by your questions and the generosity that they conveyed,” Block said. “I’ve thought a lot about the need for openness — and the need to avoid getting trapped by our own assumptions about people, careers, politics or the world in general. I think, in my opinion, much of the divisiveness in our country and in the world today is a result of facts being discarded or twisted through narrow perceptual funnels.”

Block reminded them that as they face challenges like solving homelessness, gun violence and climate change, they are not alone.

“The people who share your values and hold you accountable to your best selves — the people with whom you’ve created bonds — those are your community,” Block said. “But beyond that — this is important — the people who don’t look like you, who don’t share your worldview, who do really seem to have different values: They’re really your community, too. And your destiny is undoubtedly bound to their destiny.”

UCLA video: Commencement highlights

Graduating senior Emily Yamane, who earned her degree in applied mathematics, reminded her classmates that they are the latest in a long line of influential Bruins, mentioning Nobel Peace Prize-winner Ralphe Bunche, co-inventor of the internet Leonard Kleinrock, and Carol Burnett, who received the Presidential Medal of Freedom for blazing a trail for women in entertainment. Her classmates, Yamane continued, have already begun inspirational work that carries on that Bruin tradition.

“Among us today, we have our female athletes who spoke out against sexual abuse; students who have changed lives in Haiti, Cameroon and Nicaragua, and so many other countries,” Yamane said. “Look at the people around you: These are the people who have shaped our community at UCLA and who will shape the future of the world.”

This year’s graduating seniors have already faced challenges in their path to graduation and in their lives, including three Native American siblings who are showing students on their reservation that they can get into a top university; the son of Salvadoran immigrants whose father has worked for UCLA Housing and Hospitality Services for 18 years; and the former bus driver now earning her degree in psychology and LGBTQ studies.

Yamane highlighted her classmates’ diverse backgrounds, and praised them for overcoming a variety of struggles.

“We have come a long way: Some of us are the first in our families to go to college, some of us were Bruin-born and Bruin-bred from the very beginning,” Yamane said. She gave shout-outs to transfer students, international students and native Angelenos. “Some of us came as underrepresented or non-traditional students, and some of us sacrificed everything in order to be here. Our Bruin stories, so diverse and unique, are a big part of what makes UCLA so great.”

When it came time to turn tassels to the left and officially graduate, the arena reverberated from the volume of students and guests cheering. As a quartet sang the alma mater, “Hail to the Hills of Westwood,” students stood, cheered and swayed to the music. The volume swelled again as the graduates added their voices to the final line of the song, and threw their caps in air.