Colleagues, former students, and family of Michael Graves celebrated his life and work Sunday in a three-hour memorial at Princeton University, where the late architect taught for 39 years. Famed architects Richard Meier, Peter Eisenman, and Robert A.M. Stern; critic Paul Goldberger; and many members of the local architectural community were among those who gathered to remember Mr. Graves, who died suddenly on March 12 at age 80.

Mr. Graves “changed the rules and altered architectural debate,” said Robert Ivy, chief executive officer of the American Institute of Architects. Learning of Mr. Graves death “was as if a light had gone out.” By introducing color and wit to the architectural landscape in the early 1980’s, “his work continued to confront and challenge us at the same time,” he said. “It continued to bring us joy.”

Patrick Burke, a principal with the Princeton-based Michael Graves Architecture and Design, described his colleague and mentor as “the most passionate, optimistic, talented, insatiable, determined person I have ever known.” He added, “The most damning criticism was when he would point to your drawing on the wall and say, ‘Well, I just don’t want to be there,’” he added, to knowing chuckles from former students and colleagues in the audience.

Mary Sue Sweeney Price, former director of The Newark Museum, commented that the rebirth of Newark is often credited to the renovation and ongoing projects the Graves firm has done for the museum. Mr. Meier recalled his friendship with Mr. Graves, dating from 1972 when they shared a Manhattan art studio. Both decided to focus on architecture rather than painting. “I stopped painting, but Michael didn’t,” he said. “He continued throughout his life. It was unusual for an architect to be known for his objects as well as his work,” he added, referring to Mr. Graves product designs, “but Michael did everything.”

Paralyzed from the chest down since 2003, Mr. Graves became an advocate for people with disabilities and accessible design. He was especially passionate about the Madonna Rehabilitation Hospital in Omaha, Nebraska, one of his most recent projects. Mr. Graves was appointed to the United States Access Board by President Barack Obama in 2013. “He would always give us his candid opinions, but with humor,” recalled David Capozzi, executive director. “He attended all 12 of our meetings, including one the day before he died.”

More than one of the 12 speakers were visibly moved by the occasion. Susan Conger-Austin, a former student of Mr. Graves who is now a professor in the College of Architecture at Illinois Institute, became emotional while telling how she incorporates Mr. Graves’ philosophies in her teaching. “I try to impart to my students the responsibilities of an architect, the process of thinking, but most importantly, the principles that Michael instilled in those of us fortunate enough to have known him,” she said. “That is the living legacy of Michael.”

The memorial featured two videos about Mr. Graves and four musical selections. Slides of his work, from iconic buildings to products he designed for Target stores, were projected during the gathering.

Several people spoke of Mr. Graves’s superior abilities in drawing and the importance he placed on drawing and painting. He had a strong connection to Rome, where he won the prestigious Rome Prize early in his career and studied at the American Academy. Mr. Graves returned frequently to Rome to teach. “He’d be both super-charged and walking on air,” said Adele Chatfield-Taylor, president emerita of the American Academy in Rome. “His students worshipped him and followed him around like the Pied Piper.”

Mr. Graves’ daughter Sarah Graves Stelfox recalled her father’s notorious sweet tooth, his fondness for Mozart and Bob Dylan, and his joy at taking every ride at Disney World with his grandchildren. The spinal cord infection that left him partially paralyzed was difficult for him, she acknowledged. “But like the artist he was, he had a new creative journey. And he remained hopeful and positive.”