He later claimed it was mainly out of curiosity.
"I believe in environment more than heredity in determining your traits,
but still you have to wonder a little about your biological roots," he said.
He also wanted to reassure Joanne that what she had done was all right.
"I wanted to meet my biological mother mostly to see if she was okay and to thank her,
because I' m glad I didn't end up as an abortion. She was twenty-three and she went through a lot to have me."
Joanne was overcome with emotion when Jobs arrived at her Los Angeles house.
She knew he was famous and rich, but she wasn't exactly sure why.
She immediately began to pour out her emotions.
She had been pressured to sign the papers putting him up for adoption, she said,
and did so only when told that he was happy in the house of his new parents.
She had always missed him and suffered about what she had done.
She apologized over and over, even as Jobs kept reassuring her that he understood, and that things had turned out just fine.
Once she calmed down, she told Jobs that he had a full sister, Mona Simpson, who was then an aspiring novelist in Manhattan.
She had never told Mona that she had a brother, and that day she broke the news, or at least part of it, by telephone.
"You have a brother, and he's wonderful, and he's famous, and I'm going to bring him to New York so you can meet him," she said.