``I did this solely for the sake of the graduates,'' Quindlen said. ``I would have given a memorable speech. I would have talked about the sheer pleasure of living.''
Quindlen, a Philadelphia native and former New York Times columnist who has written two best-selling novels, Object Lessons and One True Thing, said the decision was her own. She said the Rev. Edmund J. Dobbin, president of the Catholic university, had not asked her to withdraw.
She said she was informed about objections to her planned appearance by Dobbin and her uncle, John Quindlen, a former member of Villanova's board of trustees.
``When my uncle told me of the tempest that developed, I immediately said I would call and withdraw,'' Quindlen said.
University officials declined to comment on her decision.
Almost immediately after Quindlen was announced as the commencement speaker on April 23, students and alumni who oppose abortion rights launched a letter-writing and e-mail protest, Margaret Mary Filoromo, an alumna from Downingtown active in antiabortion work, said yesterday.
Filoromo, cofounder of Villanovans for Life while a university student in the 1970s, said: ``You have to uphold the basic teachings of life and go against the culture of death, as the Pope has said. Anybody who would be against that, you can't have as a speaker.''
Well-known antiabortion activist Michael McMonagle of the Pro-Life Union of Southeastern Pennsylvania said he had begun organizing students and others to protest at the commencement ceremony.
He said plans were being made to ask each graduating senior to carry a rose - a symbol of the antiabortion movement - then walk out at the start of Quindlen's address.
About 1,800 seniors and graduate students are scheduled to receive degrees.
Quindlen was chosen by a committee of about 20 faculty members, students, university officials, and members of the Augustians, the order that runs Villanova, Barbara Clement, a university spokeswoman, said yesterday.
Clement said Quindlen informed Father Dobbin of her withdrawal via e-mail on Sunday.
Quindlen's support for abortion rights is well-known. She serves on the board of directors of the National Abortion and Reproductive Rights Action League Foundation. Quindlen said yesterday that she also supports the ordination of women and favors gay and lesbian rights.
Because she supports academic freedom, Quindlen said, she would not have withdrawn had she been merely giving a speech at the university. But a graduation ceremony, she said, is different. Even though she had no plans to discuss abortion or anything controversial in her address, she said, she would not have wanted to take away the focus from the graduates.
Quindlen, who won the Pulitzer Prize while a New York Times columnist in 1992, would have become the third member of her family to receive an honorary degree from Villanova. She lives in Hoboken, N.J., with her husband and three children.
Quindlen's replacement as speaker will be Brother Richard J. Curry, a Jesuit who is founder and artistic director of the National Theatre Workshop for the Handicapped in New York.
Curry, who has a master's degree in theater from Villanova, was already scheduled to receive an honorary doctorate.
Quindlen is not the first commencement speaker whose political views have placed her at odds with the guiding principles of the school where she was to appear.
Last fall, Gov. Whitman of New Jersey was to have received an award from a student organization at Seton Hall University School of Law, a Catholic school in Newark. But the university demanded that the awards ceremony be moved off campus because of Whitman's support for abortion rights.
Cathy Rossi, spokeswoman for the Archdiocese of Philadelphia, said that Cardinal Anthony J. Bevilacqua was aware that a number of people were objecting to Quindlen's appearance.
``The situation never reached a point where the cardinal made any direct request to the school,'' Rossi said. ``It was our hope that the commencement speaker would represent the Catholic identity of the university.''
Quindlen's decision came several days after the Cardinal Newman Society, a Catholic organization headquartered in Falls Church, Va., called upon Villanova and nine other institutions to cancel invitations to speakers who disagree with the church's antiabortion position.
Among them was La Salle University, where Mayor Rendell, who supports abortion rights, is scheduled to receive an honorary degree and give brief remarks at the school's May 23 graduation ceremony.
La Salle spokesman Jon Caroulis said that La Salle had received a handful of letters protesting Rendell's degree but that the mayor would be honored as planned.