Under the Microscope: Most of us would agree with Woody Allen when he said: "It's not that I'm afraid to die, I just don't want to be there when it happens", writes William Reville.
One of the few things we can be certain of is death. No normal person enjoys contemplating this prospect. Average life expectancy is steadily improving and science is beginning to tantalise us with the prospect of interventions that will further improve life expectancy, perhaps even to Biblical proportions and beyond. Do we stand on the threshold of immortality, and, if so, is this a good thing?
The scientific approach to extending life expectancy is to cure and control diseases associated with old age and to repair the wear and tear that accumulates in older people. The recent publication of the entire information included in the human genome offers the possibility of discovering the root cause of all genetic diseases and of curing them through genetic therapy.
However, normal human cells lose the ability to divide after they have divided a certain number of times. If greatly improved human longevity is to be achieved, it will be necessary for cells to divide indefinitely.
The genetic material in our cells is organised into long fibrous structures called chromosomes. We now know that the ends of chromosomes are capped with structures called telomeres. A telomere functions like a cap at the end of a shoelace that prevents the shoelace from unravelling. The telomere does the same for the chromosome.
When a cell divides in two, the chromosomes are first duplicated and each daughter cell receives an identical copy. However, the chromosomal telomeres also shorten every time the cell divides. After many cell divisions, the shortened telomeres cannot maintain chromosomal integrity and the cell loses its ability to divide. Scientists hope to be able to prevent telomere shortening, allowing cells to divide indefinitely.
There is good evidence that, for at least the past 160 years, average life expectancy has increased at a rate of three months a year. This improvement is attributed to improved socio-economic conditions, the development of scientific-medical technologies such as antibiotics and immunisation, and technologies to improve the quality of life of the elderly.
The goal of increasing human life expectancy is irresistible and will be tackled in stages. The first goal will be to raise the average life expectancy of 77 years to the 85 years enjoyed by Japanese women. The next goal will be to increase average life expectancy to about 120 years, matching the lifespan of the French woman who died a few years ago, aged 122. The next goal would be 150 years, and the final phase would be to add more and more years to human life expectancy with no envisioned stopping point.
At first glance, extended life expectancy seems desirable, but on deeper reflection, problems will arise. First, there will be logistical problems. The world is already overcrowded. If the average life expectancy were 500 years, birth rates would have to be reduced to a trickle to prevent the Earth becoming covered with humans like a locust plague. How would you like to live in a world without children?
But, the prospect of semi-immortality raises deeper problems. The very nature of our humanity is tied up with transience. Our notions of beauty, courage, hope, development, are all tied up with the fact that we have a limited time on this Earth. Most of us can expect to live 70 to 80 years. We have about 20 years at the start to prepare for adult life. Then about 20 years to raise a family and to get established in careers. We have another 20 years to develop our careers and maybe a final 20 years to develop personal goals, reflect on our lives, and prepare for death.
Transience conditions our experiences. Our appreciation of the beauty of a flower is sharpened by the fact we know it will fade. Year in, year out, nature plays the cycle of birth, death and re-birth before our eyes. The ultimate test of love or courage is to prematurely lay down your life on behalf of something or someone.
But, if you know you will live for 1,000 years, transience is effectively eliminated. This life would essentially be one endless chunk - more and more of the same. Human psychology may not be able to accommodate this. The problem of massive boredom rears its head. We are all aware that, enjoyable as achieving something is, going back to repeat the achievement again and again rapidly loses appeal. In a 1,000-year lifespan, would everything that makes human life bearable become meaningless by the age of 200?
Of course, the idea of immortality is not new to Christians. Christians believe in the resurrection of a glorified body that will not age or corrupt, and everlasting blissful life in communion with God. This is not a "more of the same" type of immortality such as might be offered by science, but a qualitatively different matter.
Boredom and fatigue would not set in because of infinite capacity to satisfy infinite appetites, and because people would live secure lives openly confirmed as being in true consonance with their deepest nature.
It is easy to see which is the more attractive version of immortality. It is less easy to decide whether this Christian version represents reality or fairytale.
William Reville is Associate Professor of Biochemistry and Director of Microscopy at UCC.