Peter Singer, who is professor of bioethics at Princeton University and a noted moral philosopher, admits he does not regard unborn babies as having the same value as mature humans or even some animals, until they have acquired the ability to reason and have preferences.
The debate, released today, explores the basis for the value ascribed to human life and whether morality is discovered as part of the fabric of the universe and grounded in a source beyond ourselves.
It has been released as part of The Big Conversation series and hosted by Premier Christian Radio presenter, Justin Brierley.
Singer, who is well known for defending utilitarian ethics which seeks to maximise overall happiness said: "If the disability is Down Syndrome, typically something like 85 per cent of pregnant women will opt to terminate the pregnancy.
"I think that that's a defensible decision and I think it's a defensible decision because I think it's reasonable to prefer to have a child without Down Syndrome than one with Down Syndrome."
The 'Animal Liberation' and 'The Life You Can Save' author continued: "I think I attract opposition from people who try to maintain that life with disabilities is just as good and we should not, as they say, discriminate against people with disabilities. But obviously, as I say, most people do discriminate and I think that's a justifiable form of discrimination."
In response, Andy Bannister, a speaker with Solas Centre for Public Christianity and author of the book 'The Atheist Who Didn't Exist: Or The Dreadful Consequences of Bad Arguments', argued: "I think all human beings, whether they have capabilities or they don't, belong to the human family and with that come rights and dignity."
Reflecting on the debate, Sally Phillips, the award-winning comedian, actress and prominent campaigner for those living with Down Syndrome commented: "Disability is a protected characteristic therefore we should we looking to create laws to protect babies and adults with disability - rather than to euthanise.
"I am becoming increasingly concerned about a society that has lost the ability to value the characteristics that predominate in the Down Syndrome community like gratitude, love, kindness, forgiveness and joy.
"Our society appears to be losing the ability or will to care for its weaker members and this will affect all of us if we are lucky enough to grow old. We appear to be living in a world that knows the price of everything and the value of nothing."
In addition and in the run up to the 70th anniversary of the Universal Declaration of Human Rights, Singer went on to say he also doesn't believe in to be valid.
He added, "If we were to think of it [the Universal Declaration of Human Rights] as philosophers and to take it carefully and go through it word by word and analyse it then I don't think that it is actually right.
"It is as you said a declaration of human rights and as such it tends to exclude, well it does exclude non-human animals, and claims that all humans have dignity tend to imply that non-humans don't have the same kind of dignity that humans do and I think that's not defensible either."
Bannister concluded, "I think what's interesting Peter, is while you take examples of human beings who are born profoundly disabled, I still think you'd recognise they had a degree of dignity there.
"Because I think if you met a parent of a child who was born like that, who was proposing not just committing infanticide but then chopping the corpse into little bits and frying them on the BBQ and then having them with a salad, you'd think that in some way there has been a failure of moral reasoning there to recognise that even in that tragedy there is a degree of dignity."
The Big Conversation is a unique video series from Premier Christian Radio's popular faith debate show Unbelievable? hosted by Justin Brierley.
The Big Conversation explores science, faith, philosophy and what it means to be human. Other episodes feature high-profile thinkers across the Christian and atheist community such as Steven Pinker, Jordan B Peterson, Susan Blackmore, Darren Brown and John Lennox.
For videos, commentary and the programme schedule visit: www.thebigconversation.show
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