Professor Margaret Somerville is an internationally renowned lawyer and bioethicist at McGill University in Montreal. The cover of her recent book, The Ethical Imagination: Journeys of the Human Spirit, shows a bird sitting on a man’s shoulder. Professor Somerville says that for her, the bird ‘symbolises the human spirit, imagination, freedom and the capacity and courage to explore physical, intellectual and spiritual unknowns’.

Professor Somerville argues that respect for all life, and in particular human life, and for the human spirit, should make us pause before we make decisions that our children and grandchildren will regret and be unable to remedy.

There should be “a presumption in favour of the natural” and a reverence for the mystery of life without trying to change it. While it is ethically permissible to use technology “to repair nature when it fails”, we should not use it “to realise what would be an impossible outcome through natural processes”.

Combining these ideas leads Professor Somerville to reject preimplantation genetic diagnosis (PGD). Social engineering will distort the community in which we live, she says, with all its richness and diversity. Imagine the outcome if prospective parents could test for a “male gay gene” or a gene for bipolar disorder, and choose not to have children with those traits, which are also connected with creativity.

Using technology to select children of a particular sex is also ethically unacceptable. Children should be accepted and loved by their parents unconditionally. Same sex marriages and the provision of reproductive technology, except for married heterosexual couples, is wrong because we should respect the traditional concept of marriage and “keep the biological links between parents and children” which is a “natural biological reality”.

We should not create human embryos for research by somatic cell nuclear transfer (SCNT, the ‘Dolly technique’) because that undermines the dignity of human life. And creating ‘transhumans’ (who are partly human and partly machines) will lead to “a future in which humans as we know them will become obsolete and will be replaced by redesigning Homo sapiens with technosciences such as genetics, artificial intelligence, robotics and nanotechnology”.

Many of these ideas are obviously contentious but they are advanced clearly – and at times poetically – with their foundations logically argued, if one accepts the author’s viewpoint.

For myself, many pronouncements are too absolute. I have no hesitation in allowing couples to use IVF and PGD if they have a family history of a serious genetic condition with debilitating effects and early death.

There are so many people in our community who develop disabilities during life that we will not lose our sympathy for those with disabilities by a reduction in their number, or the diversity they bring to the community. Indeed, if we have fewer people with inherited disabilities, there will be more resources to help those who acquire disabilities in later life.

Fears that prospective parents will rush to IVF and PGD for ‘enhancement’ seem ill founded as the vast majority of couples will seek IVF only to avoid extreme risks. With SCNT, it is a criminal offence to implant embryos used in research into women so those embryos cannot develop into a child. Also, SCNT embryos contain DNA almost entirely from one person so they are different from embryos formed by the fertilisation of a human egg by human sperm which contain the DNA from both parents.

And there are many types of family. What matters for a child’s development is being reared in a loving and supportive environment. The new biotechnologies have much to offer in helping us to understand cellular development, bodily functions and disease and the development of new treatments. People with ‘machines’ inserted into their bodies, such as pacemakers and bionic ears, seem to me no less ‘human’ than the rest of us.

Loane Skene is a Professor of Law at the University of Melbourne