Tuesday, May 30, 2006

Life Extension

Many things in life influence our health prospects. The genes we are born with, the food we consume, the lifestyle we live (e.g. sedentary or active), our economic prospects, our love prospects, our gender, our education, etc. One major health-related factor is our *age*.

The lifetime risk (for all races in the US) of being diagnosed with cancer, for example, is currently 45.67% (see here) . And the lifetime risk of dying from cancer is 23.56%. But our age greatly influences what the risk of cancer is at the various stages of our lives. Males who are cancer-free at 20 years of age only have a 1.11% chance of being diagnosed with cancer in the next 20 years. Whereas males who are cancer-free at 50 years of age have a 21.40% chance of being diagnosed with cancer in the next 20 years. The fact that humans are temporal beings raises a number of interesting and challenging complexities for moral theories.

As I mentioned in my previous post, I was at the "Human Enhancement Technologies and Human Rights" Conference on the weekend. The highlight of this conference, for me, was hearing Aubrey de Grey's talk about Life Extension. De Grey is biogerontologist at the University of Cambridge. He is not a philosopher and yet he gave an excellent philosophical paper on the ethics of life (i.e. health) extension. The talk was based on his published paper "Life Extension, Human Rights, and the Rational Refinement of Repugnance" in the Journal of Medical Ethics (2005;31:659-663). I have added De Grey's paper to my list of must reads this summer!

In the talk De Grey began by reflecting on the fact that many things that society once found morally repugnant are now taken to be fundamental commitments on any defensible account of morality. For example, just over a century ago many people (including many women) in Western societies found the idea of female suffrage repugnant. De Grey cited a number of interesting passages that made the point of how society's mores can change so dramatically very vivid. One of the attitudes that De Grey believes will undergo a similar transformation is our attitude towards health extension.

I must admit that I had been of mixed minds about the issue of radical human enhancements. I certainly have no objection to people utilising such interventions if they were to become safe and effective. But I was unsure (and still am) where such aims should fit in the bigger picture of distributive justice. As a prioritarian I see therapeutic aims that benefit the least advantaged as our main priority. But when one considers the health-related consequences of aging (and its socio-economic costs) the story of where human enhancements that forestall the negative effects of aging figure in the larger picture becomes more complex. De Grey certainly convinced me that these concerns warrant serious reflection and that we should (at the least) subject our existing attitudes towards life extension to critical reflection. It was a real joy to listen to De Grey's talk. He is an important figure in the debates concerning the ethics of health extension.