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The Living End:
The Future of Death, Aging & Immortality
A popular science book by Guy Brown
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Death was in the past digital - an event. It is now analogue - a process occurring throughout life, fused with aging. The decline of infections, starvation, warfare, heart attack and stroke has allowed people to reach extreme old age - yet ushered in disability, dementia and degenerative disease, with profound consequences for the self and society. In chapters echoing Dante's seven circles of hell, Dr Guy Brown explores these vital issues at various levels, from the cell, to the whole body, to society. He reveals that cell death dominates cutting edge biology - from embryo formation to cancer cures. He tracks the seismic shifts in the causes and character of death that are rocking medicine. And reveals how technological innovations, such as cloning and electronic interfaces, hint at new modes of 'survival' after death.
From the Introduction:
Once upon a time Death itself was young and virile; remorselessly scything through humanity; pervasive, undeniable and unstoppable. Now Death has grown old, and is slowly falling apart; a suppressed terror consigned to some attic of our memory. Some say that God died in the 19th century, and our Humanity in the 20th century. Will Death itself finally expire in the 21st century, holding out the prospect of immortality, and with it the possibility of us humans becoming Gods?
Death is certainly not what it was. Life in the Past was once described as “nasty, brutish and short”, but this would be a better description of Death throughout most of history. The very shortness of life tended to mean that death too was short. People died either as children or in their prime, so aging and aged individuals were rare. The most common forms of death were either by infections, by violence or in childbirth. On the whole death was rapid: people were fully alive one day, and fully dead the next. There was relatively little grey area between life and death. Of course there were exceptions: people suffered from disabilities; some lucky individuals lived long enough to age; some people died from long lingering diseases. But the average death was shorter in the past and occurred in a much younger individual.
In the Developed world, and increasingly in the Developing world too, we no longer die of infectious diseases, we no longer die quickly, and we no longer die young or in our prime. Our concept of death, inherited from history and film, is either of violent death or of a fevered soul wracked by delirium fading into the night and expiring with a final, faint breath. This might have been the average death two hundred or four thousand years ago, but the reality now is very different.
Today, the average lifespan in the developed world is about 78 years. And this lifespan is increasing by 2 years every decade. That is every decade you live, your expected age of death recedes by at least 2 years, or 5 hours per day, or 12 seconds per minute. If this trend persists (as it has done for at least 100 years) someone born today would be expected to live to the age of 100 years.
Sickeningly, there remain regions of the world still ravaged by acute forms of death, such as AIDS, starvation and war in parts of Africa. But as a whole, the developing world achieved more dramatic increases in lifespan and decreases in acute forms of death during the 20th century than in the developed world. Even in the developing world, people are now living long enough to mainly die from degenerative diseases.
Our concepts of ‘old’ and ‘old-age’ are out-of-date. It is no longer useful to categorise everyone over the age of 65 as just ‘old’ – there are the ‘old’ (65-85 years), the ‘very old’ (85-100 years) and the ‘extremely old’ (over 100 years). Just because we are old, or know people who are old, does not mean we know what it is like to be very old or extremely old. These are radically different phases of life, as different as youth from middle age, or middle age from old age.
We can not assume that what applies to old age equally applies to extreme old age. We know very little about this phase of life, but this is the fastest growing fraction of the population. If current trends persist the UK Government Actuary’s Department predicts the UK population over 65 years of age will triple from 4.6 million now to 15.5 million in 2074, and the population over 100 years of age will increase 100-fold from 10,000 now to 1 million in 2074. The future is not just old, or even very old, but is also extremely old. We are voyaging into a new realm of human life that has hardly existed before, and about which we know very little.
While we have been remarkably successful at delaying death, crucially, we have failed to delay aging. A 80 year old person today appears to be just as aged as an 80 year old several hundred years ago. This has huge consequences for life and death, both now and in the future. The incidence of degenerative diseases, such cancer, Alzheimer’s and cardiovascular disease increases dramatically with age. So as the population inexorably ages, these maladies that were formerly rare to non-existent become commonplace. A plethora of frightening new neurodegenerative conditions, such Pick’s disease, Lewy body disease and fronto-temporal dementia, have apparently appeared out of nowhere as life expectancy marches ever higher.
Currently in the US 46% of people over the age of 85 are thought to have Alzheimer’s. If current trends persist, someone born today, has a one in three chance of dying with dementia! This is not just a problem for somebody else in the future, unfortunately, it is a problem for you and me now. Current life expectancy (without any extrapolation) for someone aged 65 years in the UK is a further 17 years for a man and 20 years for a woman. So a 65 year old woman now can expect to live to 85 years (and extrapolated life expectancy could take that to 90 years), so that the probability of developing dementia is about one in four. If we include Mild Cognitive Impairment (MCI, a precursor of Alzheimer’s), then two thirds of 65 year old women would be expected to develop MCI or Alzheimer’s before they die.
Imagine the consequences if this nightmare becomes a reality. Imagine the psychological consequences of expecting to die with dementia. Imagine the economic consequences of providing round-the-clock, one-to-one care for millions of demented or disabled people for decades. Imagine the social consequences of loss of faith, loss of hope, loss of trust.
And what are we doing about it? Virtually nothing. Death, Dying and Dementia are nowhere on the political agenda. We are too afraid to think about the 3 Ds. And that suits the politicians fine – because of course it wouldn’t be easy to do anything about them.
Even now the vast majority of people in the developed world (and increasingly in the developing world) die from degenerative diseases, such as cancer and heart disease. These diseases are caused by age, and dying from them is slow and is becoming slower, so that the processes of death and aging are merging into one. Death is currently preceded by an average of 10 years of chronic ill health, and this figure is rising. But aging starts much earlier. Many of our physical and mental capacities peak at around 20 years of age, and then undergo a long, slow decline. Few people survive until death without significant physical and/or mental disabilities, extending over decades. Death is no longer an event, it has become a long, drawn-out process.
The word Death has in the past had at least three related but distinct meanings. Firstly, the process of dying, as in “The Death of Ivan Ilitch”. Secondly, the terminal event at the end of life and dying, as in “he finally expired and gave up the ghost”. Thirdly, the state of being dead, as in “he is dead”. These three meanings are located before, at and after the terminal event of life. However, if the dying process and the terminal event itself have become stretched over many years, then the three meanings of Death become mixed up, with themselves, and with aging and degeneration. We need a new theory of Death.
The digital theory of death is dying. We can no longer think of ourselves as suddenly going from being fully alive (1) to fully dead (0). In the same way we have accepted that we do not jump from being non-existent (0) to fully alive (1) at birth. Becoming a full human being is a process. We grow into it over a period of years and decades, but then we grow out of it. That does not mean that aging is growing up in reverse. They are obviously completely different processes: an extremely old person is not the same mentally or physically as a new-born baby. But growing up and growing old could be thought of as growing into and growing out of life. This would give us an analogue theory of life and death: there is a continuum between life and death. Life is not all-or-nothing, there are degrees of life; at some times in our life we are more alive than at other times. We’d all agree that at some times of the day (or night) we are more alive than others. But to assert that some people are more alive than others is a political bombshell. However, whether we like or not, the future reality where the majority of us die demented or cognitively impaired will force new concepts of life and death upon us.
Grave men, near death, who see with blinding sight
Blind eyes could blaze like meteors and be gay,
Rage, rage against the dying of the light.
And you, my father, there on the sad height,
Curse, bless, me now with your fierce tears, I pray.
Do not go gentle into that good nigh.
Rage, rage against the dying of the light.1
In Dylan Thomas’s visceral poem Life is light and Death is darkness; and in between there is the enveloping twighlight of old age and aging: “the dying of the light”. In this metaphor death, dying and aging roll into one continuous process: a dimmer-switch theory of death and aging! A dimmer-switch is an analogue device, enabling a continuously variable amount of light. We should contrast this to digital switch theory of death – a switch that has only two positions: on or off correspond to fully alive or fully dead. Thomas gives us a richer theory whereby death is mixed in with life as shades of darkness and light that may grow and fade with day and night.
But the dimmer-switch gives us a rather uni-dimensional, monotonic metaphor for life and death. We need some colour. Death is not just happening later and taking longer, its also fragmenting. There are different types of death occurring in the same person at different rates and to different extents in different people. There is death at different levels: molecular death, cell death, and organ death; death of the individual, death of the culture and death of the species. There are multiple deaths of different parts of our body and mind: death of our physical abilities and appearance, death of our various mental capacities. There is Reproductive death, Social death, and Psychological death. There is death of desire, there is the death of memory, there is death of the will to live. All these things fade away at different ages, at different rates, and to different extents.
Death is no longer a unified event. It is shattered into multiple uncoordinated processes. This is one reason it is impossible to quantify life or death. If someone’s brain is 100% dead and body 100% alive, can we say they are 50% dead: 50% alive? I think not. But neither can we say they are fully alive or dead. Nor can we hide in such simplicities when Alzheimer’s disease has gnawed away half of someone brain.
We as a global society have been remarkably successful at taming acute forms of death. Until as recently as 100 years ago, acute death was the norm - now it seems like an outrage. Yet many acute forms of death have been converted to chronic death or disability. Heart attacks have become heart failure; stroke has become vascular dementia; diabetes, AIDS, even some cancers have been converted from acute causes of death to chronic disabilities. All of these are great medical advances, but they have a down side: the conversion of acute to chronic death. This has an up-side for the pharmaceutical companies that now dominate medical research. Curing diseases does not pay - because you lose your patient. Whereas converting an acute disease into a chronic disease pays very handsomely indeed – because you convert a short-term patient into and long-term consumer of your drugs.
Patients and medics have, perhaps understandably, been more concerned to prevent death than to prevent disease. Sudden death is generally more ‘sexy’ than chronic death. Just compare the column inches devoted to acute death of young people (e.g. Princess Diana’s car crash) as compared to chronic death of old people. Yet the latter death is much, much harder for the individual concerned. We may think that chronic death from old age is ‘natural’, while acute death of the young is somehow unnatural. Of course, the exact opposite is the case. Death from old age is extremely rare in wild animals, and was rare in humans up until one hundred years ago. Only in the unnatural conditions of modern society and medicine can the exotic diseases and deaths of old age bloom. Many of these diseases and causes of death have only been recognised in the past few decades, and many more undoubtedly lie undiscovered ahead.
In Greek mythology, Tithonus was a handsome mortal who fell in love with Eos, the goddess of the dawn. Eos realised that her beloved Tithonus was destined to age and die. She begged Zeus to grant her lover immortal life. Zeus was a jealous god, prone to acts of deception in order to seduce beautiful gods and mortals, and he was not pleased with Eos's infatuation with a rival. In a classic Devil's Bargain, he granted Eos's wish - literally. He made Tithonus immortal, but did not grant him eternal youth (which Eos and the other gods obviously had). As Tithonus aged, he became increasingly debilitated and demented, eventually driving Eos to distraction with his constant babbling. In despair, she turned Tithonus into a grasshopper. In Greek mythology, the grasshopper is immortal, and this myth apparently explains why grasshoppers chirrup ceaselessly, like demented old men.
Tithonus’s fate now threatens us all – ever increasing lifespan, but with ever increasing enfeeblement, ill health and dementia. This is the Tithonus scenario, and we as a society need to decide whether we accept this fate, or do something about it.
Throughout history people have sought to escape Death and claim immortality in three different ways: spiritual, genetic and cultural. We may survive as spirits in some afterlife. We may survive through our genes passed on to our children and children’s children. We may survive though our works, deeds and memories - ‘memes’ - left to our family, friends and society in general. The desire to survive spiritually, genetically or culturally has been, and continues to be, one of the most important motivators in life. Indeed society as we know it (religion, family, culture) would be impossible without such motivators.
Whether or not we believe that a spirit survives after death, genes and memes certainly can. But they too can die or slowly fade away. Our children’s children may not survive or breed. Even if they do, our genes will be slowly diluted and mutated beyond recognition. More importantly perhaps, an individual’s life can leave a lasting impression on society and on those who knew him/her, via the memories and surviving effects of the deceased’s ideas, works and deeds. Such things might be as small as a remembered kindness, or as large as a scientific theory. In the end all of them, in different ways and rates, will fade and die. Prior to what we call the terminal event of Death little bits of life fade away (our abilities, energies and desires), but the process continues after Death, as what is old is inexorably replaced by what is new.
The analogue nature of Death has important implication for our concepts of life and self. Since at least the Renaissance the concept of the individual self has become increasingly central and monolithic in Western thought. The Self became the unified, indestructible, unchanging atom of society. Just as we had an atomic theory of matter, the concept of soul gave us an atomic theory of self: the core of a person that was completely separate although similar in different people, unsullied by life, and unanalysable into component parts. But if we accept that death is a process changing multiple components of ourselves throughout life, then we also need to consider the possibility that the self is not the same self throughout life. Are you really the same person you were as a child, or you were ten years ago, or will be at 70 or 100?
The notion that someone may be partly dead seems absurd, until we encounter someone has “unsuccessfully” aged or has Alzheimer’s. If we entertain the notion that beyond death various components of ourselves, spiritual, genetic or cultural, will survive in non-individual form, then our concept of the monolithic self may fracture and dissolve into a web of interacting components, the genes and memes that we share with our family and culture. The classical atomic theory of self, (where the self was single, separate, unified, digital and unchanging), needs to be replaced by a wave theory (where the self is multiple, overlapping, distributed, analogue and changeable). If the self is not digital (all or nothing), this implies that we can loose parts of the self (for example by forgetting or by changing part of the body or mind), but it also suggests that parts of the self may survive death of the individual.
In the 20th century Death replaced Sex as the taboo subject we could not talk about, yet we all end up “doing it”. The suppressed dread of death has allowed our society to sleep walk into a situation where people face real horrors at the end of life, simply because we can not face dealing with the issue of how people should exit life. Death has been banished to hospitals, the worst possible place to end life. Medicine has become devoted to keeping people alive at any costs, rather than helping people die. Huge resources are devoted to preventing infectious diseases and heart attacks, possibly the ideal way to die, which inevitable condemns people to die by more protracted means.
Only by recognising that death is part of life and that many people experience a living death at the end of life, can we make sensible decisions about whether people should be allowed to choose a dignified exit from life. We all recognise that we need to make provision for a pension, but how many of us are making provision for dementia? If society really cared about the last ten years of life to the same degree as the first ten years of life, then we would have a real chance of preventing aging and dementia before it was too late. If not, we have the real prospect of creating Hell on Earth, and locating it at the end of Life.
Death and aging will be the defining problems of the 21st century. If death continues to recede while aging continues, then our world will turn grey and then white. The most obvious impact will be economic: supporting a huge and ever growing population of increasingly disabled and demented, very old people will be crippling to all our economies. The projected scale of the looming pensions crisis still takes a very optimistic view of the balance between death and aging in the future. A more realistic view would see real damage to the economies of both the developed and developing world.
Perhaps more seriously, each individual will have to face up to a slow, grinding, degrading journey into darkness, and possibly dementia. The potential of this to change our outlook on life, and the consequent impact on society should not be underestimated. Global terrorism may directly affect tens of millions of people, and global warming is likely to affect hundreds of millions. But the Tithonus scenario will strike billions in the most direct and personal way possible, rotting their bodies and brains from within.
However, looking on the bright side, many researchers are now seriously suggesting that aging may be completely solved during the 21st century. The promise of stem cells, cloning, RNAi, gene therapy, the sequencing of the human genome and the deep understanding of our biochemistry, suggests it is just a matter of time before we can make humans for all practical purposes immortal. However, not everyone is happy at the prospect of universal immortality. Bioethicists and politicians are reaching out to restrain these sciences, for example banning cloning, stem cell research and genetic engineering. But aging and dementia are not natural, and we should not accept them as our inevitable fate – allowing millions to suffer in silence.
A flood of new evidence is starting to have an impact on our concepts of life and death. Genetics and genomics have found multiple genetic switches that can dramatically extend or shorten life span (at least in worms!). Evolutionary biologists have given us an understanding of the evolutionary origins of aging. Cell biology has uncovered a programmed process of death that occurs throughout life, and is indeed essential to it. Medical research made massive progress in understanding how we die. Medicine confronted issues such as the definition of death, an acceptable quality of life, rationing of health care to the elderly, euthanasia, the treatment of the incurable dying, and the handling of the dead body. The increasing interaction of psychology, philosophy and neuroscience has brought new insights into the composition of self and its changes through life and death. The relatively new science of aging has discovered an inexorable process of decline at the heart of our molecular machinery, but also claims to have found potential ways to interfere with that decline.
Leading aging researchers are now urgently calling for society to prepare for an era of dramatically extended life span. Scientists, doctors, economists, social planners, philosophers, theologians and even politicians are waking up to the massive impact that aging and increased life span will have on our society. For ourselves and our children we now need to urgently consider the future of death, dying and dementia. And in this book I intend to “rage, rage against the dying of the light” as well as exploring options for changing our fate.
Praise for The Living End:
'Brown makes an engaging and persuasive case for a complete rethink of the place of death in modern life.' James Wilsdon, The Financial Times.
‘This book’s new view of death as a slow, analogue process, rather than a digital on/off switch, is intelligently, imaginatively and emotionally argued.’ Professor Chris Cooper, University of Essex.
‘A well-informed, wide-ranging and thought-provoking book that is skilfully written and a pleasure to read.’ Professor Andrew Halestrap, University of Bristol.
‘Not only well written, but also timely and fascinating.’ Salvador Moncada, Director of the Wolfson Research Institute, University College London.
‘Erudite, eloquent and entertaining.’ Douglas Kell, Director of the Manchester Centre of Integrative Systems Biology.
'Remarkably accessible' Arthur Salm, San Diego Union Tribune
‘Spectacular.’ Mervyn Singer, Professor of Intensive Care Medicine, University College London.