Mr. Newsom, in interviews, has pledged to increase spending on early childhood education and a few other programs, but nonetheless said he would continue the fiscal practices followed by the departing governor.

This is not a moment of transition only for Mr. Brown; it is one for California, as well. The Brown family has been an integral part of political life here since Pat Brown, Mr. Brown’s father, was elected governor in 1958. Jerry Brown has served as governor twice, as mayor of Oakland, as state Democratic Party chairman and as attorney general. His sister Kathleen served as state treasurer.

But Mr. Brown, 80, who married for the first time in 2005, never had children. There is no one left to carry the family legacy. He is stepping down because of term limits; he said in an interview he probably would not have run again even if there was no term limit statute, if only because history has not looked kindly on governors of big states who seek third terms.

Not that he wasn’t tempted.

“What will I not miss?” Mr. Brown said, parrying a question with a question as he spoke at a luncheon. “I like it all. I like fund-raising. I like sparring with the press. I like attacking my opponents. I like being attacked. I like the whole thing. People in this business like attention and you get a lot of attention as governor.”

A few days later at the ranch, Mr. Brown said he did not know whether he would attend Mr. Newsom’s inauguration. “These are vulgar details,” he said. “I have a whole staff in charge of details. I’m more about the large, larger questions that are affecting our times.” (Short answer from one of those staff members: Of course he is.)

Mr. Brown declined in an interview to offer Mr. Newsom advice — that, he said, would be unseemly — though he arched his eyebrows when asked if Mr. Newsom had sought his counsel during this two-month transition.