He has been labelled a “Nazi” and branded “the most dangerous man on earth”. And yet he has also been hailed as “one of the world’s 100 most influential people” and “among the most influential philosophers alive”.

Welcome to the schizophrenic world that surrounds Peter Singer, the Australian-born moral philosopher.
Loved and loathed, divisive and incisive, one thing cannot be denied: the Melbourne-raised, Oxford-educated ethicist, who has been professor of bioethics at Princeton University in New Jersey since 1999, is a towering intellect who has provoked debate about critical issues of humanity — abortion, infanticide, euthanasia, eugenics and animal rights.

The 65-year-old Singer, who lost three of his grandparents in the Holocaust, has also stirred debate on several key issues that affect Jews and Israel, including the Israeli-Palestinian conflict and ritual slaughter.

He struggles with the ethics of Israel’s establishment, having described the country’s foundation as “a grave injustice to Palestinians” and regarding its history since 1948 “as a series of repercussions from the injustice of its foundation”.

“Clearly, there were moral flaws in the setting up of the state of Israel without proper consultation and participation by Palestinians,” he says. “But that was a long time ago now, and I think that instead of looking backwards, we should try to work out the best solution for all those living in Israel and the occupied territories.”

He has occasionally ventured from academia into activism, signing a petition in 2010 renouncing his right of return to Israel because it is “a form of racist privilege that abets the colonial oppression of the Palestinians”.

The petition, issued by the far-left Independent Australian Jewish Voices, an offshoot of a British group founded in 2007, stated: “It is not right that we may ‘return’ to a state that is not ours while Palestinians are excluded and continuously dispossessed”.

But, he says, he does not subscribe entirely to the views of the dissenting Jewish group. “I take my own stance on what I judge to be right,” he says. “I have sometimes declined to sign statements from IAJV, for example because I thought they were too one-sided, and while rightly criticising actions taken by the Israeli government, did not also criticise actions taken by Hamas.”

And he has not just irked Zionists. Singer has been opposing ritual slaughter since the 1970s, when he wrote Animal Liberation, which catapulted the issue of animal rights into the headlines and prompted some to describe Singer as the “founding father” of the animal liberation movement.

“Even when shechita is at its best, it is still less humane than modern slaughter, properly done,” says Singer, who has been a vegetarian since 1971.

He rejects the view that Judaism forbids causing animals unnecessary suffering, arguing that “no one has a right to inflict needless suffering on another sentient being. And [ritual slaughter] is needless, because no one with access to a wide range of food needs to eat meat”.

A promoter of freedom of speech, he has defended proponents of Holocaust revisionism, such as David Irving. “If there are still people crazy enough to deny that the Holocaust occurred, will they be persuaded by imprisoning people who express that view?” he asked in 2006 when Irving was jailed in Austria for Holocaust denial.

“On the contrary, they will be more likely to think that people are being imprisoned for expressing views that cannot be refuted by evidence and argument alone.”

And yet critics equate some of his theories with Nazism. American anti-euthanasia advocate Wesley J Smith labeled Singer’s 1995 book, Rethinking Life and Death, as “the Mein Kampf of the euthanasia movement”.
Singer supports law reform to allow people to end their lives if they are terminally ill. He also argues that a seriously disabled baby’s life should be actively — and humanely — terminated if the baby’s parents and the doctor decide, not just by withholding or withdrawing life support, which he says can lead to a slow and inhumane death.

“Killing a defective infant is not morally equivalent to killing a person,” he wrote, although he notes that by “person” he means someone who can anticipate the future. “Sometimes it is not wrong at all.”

This provoked a storm of protest from pro-life and disabled rights activists, among them Diane Coleman, the founder of Not Dead Yet, a US-based disability group that opposes euthanasia, who called Singer “a public advocate of genocide and the most dangerous man on earth”. Singer says of critics who use the “Nazi” label: “It’s absurd and it makes me sad”, adding that it “devalues the atrocities that the Nazis committed”.

His latest crusade, however, is global poverty, which he argues is morally indefensible and can be substantially alleviated, if not entirely eradicated, by charity, picking up on the Jewish idea of tzedakah.
In his book The Life You Can Save, he proposes a sliding scale commensurate with income; most people in the developed world should donate five per cent and the affluent should give much, much more. As for himself, Singer donates about 25 per cent of his income to non-government organisations, mostly those “helping the poor to live a better life”.

Although his family has a Passover Seder — “with a beetroot instead of a lamb shank” — and he celebrates Purim with his grandchildren as well as Rosh Hashanah, Singer says Jewish traditions “do not play much of a role in my life”.

But he concedes his family history did influence the development of his theories. “As three of my grandparents died in the Holocaust, and the fourth was fortunate to survive in Theresienstadt, I am sure that it had some impact on my thought — on my abhorrence of cruelty, of the naked use of power over the defenceless, and, of course, of racism.”

His family’s background also informed his views on religious belief. His parents gave him the choice of whether to be barmitzvahed; he declined.

“I never believed in a God,” he says. “There may have been times when I wondered if there might be a God, but it always seemed to me wildly implausible that a God worth worshipping could allow the Holocaust to occur.”
Singer has recently been awarded a Companion of the Order of Australia, the highest civilian honour bestowed by the nation, for his “eminent service to philosophy and bioethics”.

“It shows you don’t have to be a conformist to be recognised by your country,” he says.
“But I guess the most important thing for me is still having people tell me that one of my books has changed their life — they’ve become a vegetarian, started donating to organisations working to reduce global poverty, and so on. They’re doing good and feeling better about their lives too.”