“Half the class is not from Practical Ethics,” someone said behind me as I sat down in the second row of a nearly full McCosh 10. They were not wrong — I, like many, had come to see Peter Singer, the 24-year Ira Decamp Professor of Bioethics, in his last lecture of his Princeton teaching career.
A book pile of “Animal Liberation” vanished in seconds into the eager hands of students. Many professors lined up in the front row as well. Once Singer began, he displayed a slideshow that recounted his time at the University.
The second slide was a New York Times 1999 article about the controversy he caused with his initial appointment, particularly from disability rights activists who disagreed with his views on the ethics of killing severely disabled infants.
Singer, according to one analysis, is Princeton’s seventh most prominent professor. On the eve of his retirement, Singer and a number of his students sat down with The Daily Princetonian to discuss his prominent career in moral philosophy. The controversy that Singer sparks is a major part of that story, especially in Singer’s retelling. Singer’s students stressed the quality of his teaching and his role in promoting an interest in moral philosophy.
Singer might be known to the public in ways that generate mixed reactions. A disability rights activist called Singer “a philosophical hypocrite,” “an enemy of civilisation,” and “the most dangerous man in the world.” Singer has often been the subject of protests, including when he was appointed in 1999.
Singer is also known, however, as the godfather of the Effective Altruism (EA) movement which has gained a significant public profile. Time Magazine included him on the list, “The 100 Most Influential People in the World.” Singer is well-known for his influential publications on giving, bioethics and the modern animal rights movement, such as his paper, “Famine, Affluence, and Morality,” and his book “Animal Liberation.”
Singer’s class remains popular on campus, especially in his final semester. Singer said in an interview with the ‘Prince’ that interacting with students has been his favorite part of teaching.
“What I like about Princeton students is that there are many among them who are ethically good and really concerned about trying to use the privileges of a Princeton education to make the world a better place,” he said. “It’s encouraging that there are quite a lot of students who are interested in that and are idealistic about what they want to achieve, not just thinking about their own well-being or material interests.”
This year, Singer’s Practical Ethics course has over 200 students enrolled. His course offers students philosophical frameworks to think about ethical dilemmas ranging from abortion to animal cruelty, global poverty to war ethics. He has also taught a graduate seminar called Consequentialism, but undergraduates can enroll with permission.
Kerrie Liang ’25, a philosophy major who took the class two years ago, said she sometimes disagreed with the utilitarian views Singer presented in the classroom. Utilitarianism, a school of ethical thought, is concerned with maximizing good for the greatest number of people.
Liang is a head Prospect editor for the ‘Prince.’
“Because Singer lives by the utilitarianism framework, he does have some very extreme views that he is very unapologetic about,” Liang said in an interview with the ‘Prince.’ “I think that there’s something deeply troubling about quantifying how good your life is, versus how good someone else’s life might be.”
“I was never too afraid to bring up ideas that directly opposed his,” she added. “I felt like he was very fair.”
“It’s much better to allow people to speak, and then argue against what they say, particularly in universities,” Singer said in an interview. “I think that’s what universities should be for, having debates in a civil way over differences and trying to provide information for people and explain why some people hold one view and some people hold another view.”
Singer often invites guest speakers who disagree with him and/or each other to speak to his class of students. He recently invited two female activists with opposing positions to debate on abortion: Terrisa Bukovinac, founder of Progressive Anti-Abortion Uprising, and Frances Kissling, president of the Center for Health, Ethics, and Social Policy.
“That class surprised some people because the person who was presenting the position against abortion was an atheist,” Singer remembered, “and the person who was presenting the position in favor of allowing women to have abortions was a Catholic. I think that upsets some people’s stereotypes.”
Maki Flauta ’27, a current student in Practical Ethics, said that Singer’s course has helped her to explore the “why” behind her beliefs.
“The nature of the class involves a lot of personal topics that are examined on a philosophical level, with things like abortion and vegetarianism,” Flauta said, “Singer’s class taught me how to justify my beliefs in a way that is principally sound.”
Joshua Yang ’25, a philosophy major who took Practical Ethics as a first-year, said that “the rigor of the philosophy” made him reconsider his stance on abortion.
Yang is an associate Prospect editor for the ‘Prince.’
According to Yang, Singer is also pro-choice, but believes that abortion is equivalent to euthanizing infants after birth.
“I came into the class being fairly pro-choice,” Yang said. “I’m not saying I necessarily agree with [Singer’s argument]. But it seems like that logically follows. And that poses an issue for pro-choice people. You’re either going to have to bite the bullet on that conclusion, or you're gonna have to think harder about it.”
Because Singer is the faculty sponsor of the Human Values Forum (HVF), he attends the forums’ weekly Monday dinners for students and professors.
“It always surprises me how such a towering figure in philosophy is so genuine and genial,” Ethan Magistro ’24, president of HVF, wrote in an email to the ‘Prince.’ “Professor Singer’s dedication to HVF for over 20 years has been outstandingly generous — he attends nearly every meeting.”
“I probably disagree with about 60 [percent] of Professor Singer’s views,” Magistro continued, “but he’s a reasonable thinker who often has compelling arguments — there are many times when his points have made me think critically about my own arguments.”
The bioethics professor remains in contact with many of his former students. One of them, Jake Nebel ’13, returned to Princeton this year as a philosophy professor and associated faculty at the University Center for Human Values (UCHV).
“Professor Singer was so generous with his time and his feedback and comments,” Nebel said. “He even helped me turn my final paper for that seminar into my first publication. That made me want to pursue philosophy as a career for the rest of my life.”
Steven Kelts, a lecturer in the UCHV, has been Singer’s head preceptor for Practical Ethics for the last four years, managing 20-25 precepts each cycle.
“[Singer] was one of the most conscientious instructors on campus,” Kelts said. “It’s really been an honor.”
Kelts does not think that the University will find a replacement professor for Practical Ethics. “The idea of Practical Ethics without Peter Singer seems sacrilegious,” Kelts added. “It’s his identity, it’s his stamp that he’s left on this place.”
Even in his last week of teaching, Singer has continued to embrace controversy. He invited Holly Lawford-Smith, a philosophy professor at the University of Melbourne, to speak to the class. Smith argues that it is legally and morally wrong for anyone born biologically male to self-identify as a woman.
Singer brought Smith on campus because he thought her ideas were worth exploring. “I think there are questions about whether simply identifying as a gender is enough to change one’s legal status,” Singer said.
On Dec. 6, the University Center for Human Values hosted a talk by Smith titled: “Is it morally wrong for a man to claim to be a woman?” Smith’s lecture was counter-programmed by Catherine Clune-Taylor, an Assistant Professor of Gender and Sexuality Studies. Clune-Taylor hosted a separate event on the same date and time about Sex & Gender Complexity in Scientific Research.
When asked to comment, Clune-Taylor said she preferred to have “the events stand for themselves.”
Singer expressed disappointment in the alternative event, saying he would have preferred to “have both sides in the same room.”
“It’s saying our group is going to talk about this and your group is talking about that,” he said, “Instead of coming along and listening to a different viewpoint.”
Singer has focused more on building spaces for controversial thought in recent years. He founded the Journal of Controversial Ideas in 2021, which “offers a forum for careful, rigorous, un-polemical discussion of issues that are widely considered controversial.” The Journal has published articles that have justified pedophilia as a sexual orientation and equated mandatory vaccination to sexual harassment.
As Practical Ethics has come to an end, Singer says he plans to get started on new projects, such as publishing a book about turkeys for the Princeton University Press by next Thanksgiving, and creating a podcast as an alternative medium for communication.
Reflecting on his time at Princeton, Singer encouraged young people to step up. “Think about your life, especially if you are a Princeton student. Think about how to use that for good. You will also find that that’s a more fulfilling way to live,” he said.
Chloe Lau is a staff Features writer for the ‘Prince.’
Please send corrections to corrections[at]dailyprincetonian.com.
Correction: A previous version of this piece incorrectly stated the host of Smith's Dec. 6 talk; it was at the University Center for Human Values, not the Human Values Forum.