BERKELEY -- Gov. Jerry Brown said Monday he was "digging deeply into" the questions surrounding the safety of the new San Francisco-Oakland Bay Bridge, and said he could not commit to a scheduled Labor Day opening for the new span.

"I take it very seriously and that thing is not going to open unless it's ready," he said. "The engineers are telling me that they're doing the kind of work that will be needed for that to happen."

Brown's comments came before his commencement address to political science students at UC Berkeley, where he received his undergraduate degree 52 years ago. In a 10-minute speech to hundreds of graduates and their family members in UC Berkeley's Greek Theater, Brown warned of the dangers of climate change, and encouraged each political science graduate to "get ready to be an active citizen."

The speech was Brown's first public address at a university campus since his campaign for higher taxes last year. Brown's outreach effort focused on galvanizing young voters, and he credited students for helping in the passage of Proposition 30.

"You helped make that happen," Brown said.

Joined by his wife Anne Gust Brown and wearing a ceremonial cap and gown, the governor quoted his former UC Berkeley political science professor, and talked about the pride, and some shame, he felt more than five decades ago at his own graduation.

"It was kind of embarrassing that my father was handing me my degree," Brown said, noting "nobody knew I was the son of the governor until I graduated. And by the way, he wasn't that popular at that moment in time."

Though Brown took just one political science class at Berkeley (his degree was in Latin and Greek), that class with Sheldon Wolin made an impression. Brown quoted Wolin in his speech Monday.

When he was plotting out how to make the case for Proposition 30, Brown turned to a book by Wolin for guidance. "I like political theory," he told graduates Monday. "It is more coherent than political practice."

ALSO:

Brown unveils cautious budget for deficit-free state

Legislature's analysts to weigh in on Jerry Brown's budget

Jerry Brown's budget plan would increase state obligation to schools

anthony.york@latimes.com

@anthonyyorklat