Health - The Struggle for Life

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Introduction

I wish to talk today ostensibly about the notion of health from a biological angle. However, what I mean by a 'biological angle' may not be what is typically meant by that phrase.

I currently lecture in the Department of Biological Sciences at the University of Chester. However, when I first when to Chester it was as a lecturer in Human Biology in the Department of Health and Community Studies. (I was 'internally reorganised' in the late 1990s.) Human Biology was, in fact, the title of my undergraduate degree, whereas my doctorate is in anatomy and my master's degree is in the history of philosophy. Interspersed with that, I practised as a radiographer, and taught students of medicine, dentistry and most of the clinically allied professions.

However, it was only when I was in the Department of Health and Community Studies that my particular interest in health was sparked. In the mid-1990s, I was asked (or rather told) by my then head of department to take over the teaching of a postgraduate module entitled 'The Biology of Degenerative Disease'. It was not clear to me what was meant by 'Degenerative Disease'. Although it would have been the obvious thing to do, I did not want to go to those who had previously taught the module and ask them – at least not immediately. I wanted to develop some views of my own first. My searches (in those proto-internet days) were not very fruitful. I only found one book which used the phrase 'Degenerative Disease' in its title and that was a book of veterinary medicine. However, what I did uncover was a philosophical debate about the problems of defining both health and disease. Something I had been quite unaware of before. Like most people I had largely taken the words 'health' and 'disease' for granted. After all, they are ordinary everyday words; we all know what they mean. At least, we do until we are called upon to give a precise definition.

The situation is analogous to a problem St Augustine had with time.

"What then is time? If no one asks me, I know what it is. If I wish to explain it to him who asks, I do not know." (Saint Augustine - Confessions Bk. 11 Chp. 14.)

He notes that he knows what time is until it comes to having to explain it. Then he is stuck. Nowadays we know that time is the fourth dimension but merely saying that that is the case does not get us much further in saying what it is. When trying to come up with a precise definition we need to avoid questions such as 'If time is the fourth dimension, what then is a dimension?' and 'What is time's relationship to the first three – and to any subsequent – dimensions?' So, what appears to be a simple question can be deceptively complex. These are not mere philosophical ramblings. Health status can be a contentious issue when it comes to welfare benefits, compensation claims and dividing up limited resources.

When I took on the 'Degenerative Disease' module, I was also becoming aware of the advent of Darwinian Medicine. This was fortuitous. I had already been wondering how the health and the clinically-related subjects I had previously been teaching could be linked to evolutionary theory. Darwinian - or as it is now more generally known - Evolutionary Medicine, holds that evolutionary theory should be as much a part of medicine as it is a part of biology. After all, evolutionary theory is, in effect, the Grand Unifying Theory of biology. What physicists still seek, we in biology already have. Without evolutionary theory, biology is more about describing and cataloguing than explaining. The eminent Ukrainian-born biologist Theodosius Dobzhansky (1900-1975) went so far as to say that 'nothing in biology makes sense except in the light of evolution'. The originators of Darwinian Medicine - Randolph Nesse and George Williams - extended this to suggest that 'nothing in medicine makes sense except in the light of evolution'. So biology and medicine were beginning to be linked in new ways. Certainly, there are insights to be had from applying evolutionary theory to matters of clinical concern. Although whether, after some twenty years or so, evolutionary medicine has explored all the avenues down which it might go, I doubt.

Another thing I got from my time in the Department of Health and Community Studies was interaction with colleagues from the social sciences. We were set up to be a deliberately multi-disciplinary department. Sociologists, psychologists and biologists of different description had been brought together over the years. One object of discussion was the medical – or as it is sometimes called the biomedical – model. This model was, for my social science colleagues, usually an object for severe criticism – often in quite derogatory terms. After all my years in clinical circles, this was the first time I had heard of this model – at least, by name. It appears that I am not alone in this. Biologists are usually unaware of the existence of this or any other such model. That is not to say that they do not follow any model in the sense that they follow a particular way of thinking. Many gravitate somewhat instinctively to the medical model of thinking unquestioningly, oblivious to the fact that there might be other approaches.

Similarly, most people involved in clinical practice are unaware of the principles of evolutionary theory. The type of biology upon which they tend to draw is that involving technical lab-based sets of procedures such as assaying different biochemical and physiological parameters. Evolutionary theory is not something that is usually broached in a clinical context when more practical concerns are pressing.

Modern evolutionary thinking began in earnest with Charles Darwin's (1809-1882) 'Origin of Species' (1859). Or, at least, that is the title by which it is now known. Victorian writers had a penchant for more florid titles. The full title here is 'On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life'. (Here 'races' means types or varieties in relation to plants and animals. It does not refer to the human race or human racial differences.)

What I want to focus attention on here is the 'Struggle for Life' part of the title.

This is, of course, is where I get part of my title. I suggested that those who work in a clinical setting may call upon the biological techniques available in laboratories but that they do not draw upon biological theory in its fullest sense; they do not draw upon evolutionary theory, in particular. Were they to do so then the notion of 'the struggle for life' should, I suggest, be uppermost in their minds. Everybody who goes to see a doctor does so in order to obtain help or advice with their particular 'struggle for life'. The 'struggle for life' is about the quality of one's life, with maintaining or enhancing that quality, with staying alive as best and for as long as one can.

In a nutshell, the 'Selection' to which Darwin's title alludes is the practice adopted by plant and animal breeders of choosing - that is, selecting - which features they want to enhance or perpetuate in their species of interest. In order to foster a particular characteristic, such as shape, size, colour etc., only those specimens with that characteristic are used for breeding. What is easily overlooked is the fact that those without that characteristic are discarded - uprooted or culled. If we are dealing with animals that may sound callous but that is what has typically gone on.

Darwin spotted that a similar process goes on in nature. Particular features were being perpetuated while others were not. Again, something that is easily overlooked is the fact that certain characteristics aid the struggle for life. Those without those characteristics may not do so well in the struggle and some may even perish. What is more, not doing well and perishing can be a very unpleasant business.

We often think of natural selection in terms of how natural history documentaries present it on television. The slowest, least agile member of the herd is pounced upon and quickly dispatched by a predator that has been patiently stalking its prey unseen. This completely overlooks the other rigours of just staying alive. Predators aside, the process of living is not a simple or easy one. There is food and drink to be found. Shelter may be required. One must not get too hot or too cold. One must keep clean and avoid the effects of parasites and pathogens. There are no paradises or Shangri-las on this planet. All living is a struggle for existence. When Alfred, Lord Tennyson (1809-1892) famously described nature as 'red in tooth and claw', it was in a poem lamenting the early demise of his friend Arthur Henry Hallam (1811-1833) who had died of a cerebral haemorrhage at the age of just 22. The phrase 'red in tooth and claw' may evoke for us images of antelopes being eaten by lions but there is a more salutary one that confronts us all.

The problem of defining health - and disease.

I mentioned earlier that when told to teach the 'Degenerative Disease' module I came upon a philosophical debate about the definition of health and disease. This has been a long, drawn out and inconclusive debate between very able philosophers of medicine who nevertheless have been described as reaching an impasse (to put it tactfully) or, as somebody put it (less tactfully) 'up a blind alley'. Interestingly, relatively few clinicians have concerned themselves with definitions of health or disease. Perhaps that is because, as I suggested earlier, we already 'know' what they are – until we try to say what they are, of course. Under the editorship of Richard Smith, the British Medical Journal, in press and online, has, over a number of years, continued to raise the question 'What is health?' As Smith notes in a BMJ blog:

"Last week about 30 of us spent 36 hours in The Hague discussing whether we could produce a new definition of health - and eventually deciding that we couldn't."

In other terms, over 1,000 ‘man hours’ of thought were expended to no avail. The discussions in The Hague having failed to achieve their goal, Smith also noted that the World Health Organization (WHO) was having problems with its own definition. The WHO definition is perhaps the most widely cited definition of health available. It is short and memorable suggesting that …

"Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity."

First presented in the Charter of the WHO in 1948, this definition remains an elegant piece of writing. Not least, it uses a tried and tested literary device: the 'rule of three'. Furthermore, it has proved durable while, at the same time, proving to be the object of much debate and criticism. Significantly, Smith notes, that the WHO is now becoming aware that "… the definition is not operational and so doesn't allow measurement of health".

It was following the establishment of the WHO with this founding definition that interest in the definition of health seems to have begun in earnest. From fairly modest beginnings in the medical literature of the 1950s and 60s, debate began to become more serious from the mid-1970s taking place largely in the philosophical literature. It was at that point that Christopher Boorse - an American philosopher - published the first of a brief series of articles which sparked what has been an intense source of debate ever since. Contrary to the WHO definition, Boorse saw no problem in defining health as the absence of disease or infirmity. In so doing, he proposed what has been dubbed the Bio-Statistical Theory of disease which saw disease as a statistical deviation from the norm. This embodies a key part of the medical model which sees health as what is statistically typical and disease as what is statistically abnormal. This has been criticised as 'naïve normalism' and, it has been suggested, represents the prevailing view to be found in most schools of medicine, nursing and the like. Certainly some textbooks adopt this view even going so far as to use normal distribution curves to make the point.

Noticeably, when health and disease are represented graphically they are often shown at opposite ends of a linear scale. If a horizontal line is used, disease typically appears at the left end of the line and health at the right end.

If a vertical line is used, disease appears at the bottom and health at the top.

This, deliberately or otherwise, adopts the convention that as one moves from left to right or bottom to top on a graph, things become more positive. Hence there is a tacit inclusion of value judgements: health is being equated with the conventionally positive ends of axes; disease with the negative ends.

Indeed, the problem of value judgements and the difficulty of excluding them has been a particular problem for those trying to define health.

We instinctively want to describe health as something good and disease as something bad. This begs the question, what is it about health that is good? and also what is it about disease that is bad?

In these representations, there is also an underlying assumption that health and disease are continuous with each other. For this to be the case, both disease and health must be commensurable. That is, they must be capable of being measured by the same, common standard and so belong on the same scale.

This, so far as I am aware, has never been established. Indeed, I would go so far as to question whether this could be the case. What can be said to be commensurable and so part of a genuine continuity, is how one feels. One may say that one feels 'well', 'unwell' or perhaps just 'OK' meaning somewhere in-between.

Here a distinction must be drawn between one's experience of oneself and one's physical state. One may feel fine but still have internal physical lesions of which one is unaware. In this scenario, one is able to go about one's daily life unimpeded; the lesions do not intrude and may remain unknown almost indefinitely. Conversely, one may feel quite unwell without any lesions or discernible physical reasons for feeling that way. In this scenario, one will not be able to go about one's daily life easily even though there appears to be no physical reason why not. In short, how life is led – how one goes about one's ordinary daily life – is determined to a significant degree by how one feels.

Going about one's daily life is part of the struggle for life. How one feels influences how one goes about that struggle and how successful one is in that struggle. This, I would like to suggest, is something that needs to be more fully appreciated and explored. It is easy to overlook this in modern western societies where food and drink are readily available, where there is heating, air conditioning and plenty of ways of keeping clean. The struggle for life relies on an extensive range of feelings and experiences. Hunger and thirst, pleasure, pain and even mild irritations are all important feelings to which we must respond appropriately in order to ensure our continued existence.

A biological history of the human (and pre-human) struggle for life

The human struggle for life can be said to have a long clinical history.

Here I am choosing my words deliberately. When I say 'clinical' I do not want to invoke images from the history of medicine necessarily. Neither do I want to refer to the clean, antiseptic environments found in modern clinics. Instead I choose the word 'clinical' because it comes from the Latin word meaning bed. It is at the bedside that the human struggle for life often takes place and has done so over many thousands of years.

Histories of medicine frequently begin in the ancient Greco-Roman world.

However, bedside care goes back much further. The practice of trepanning can be dated to around 6500BP.

Although this is typically viewed as an early form of surgery, it also points to a response by members of early human groups to individual suffering and to a willingness to provide care. Certainly, following trepanning, the subject would have been confined to bed and their needs would have to have been catered for. They would have been unable to cater for their own needs for some time. (We know that these people survived because the bone edges show signs of healing.)

Older still is evidence that our cousin species, the Neanderthals, also cared for each other. Four of the six adult Neanderthal skeletons (dated at between 60,000-80,000 years BP) excavated near Shanidar (Northern Iraq) show lesions. In particular, the specimen of a 40-50 year old male now known as 'Shanidar 1' was shown to have a severely atrophied right arm - as well as a number of healed fractures.

Furthermore, the shape of the bones in his right leg and foot suggest that he walked with a marked and possibly painful limp. What is particularly notable is a fracture sustained to his left orbit which would have caused partial if not complete blindness in his left eye. To have lived to what was, by the standards of the day, a relatively old age, 'Shanidar 1' would have had to have been cared for by his fellows for much of his life. He is likely to have received assistance with the activities of day-to-day life. That he lived to such an age may even reflect that he was spared the more hazardous aspects of Neanderthal life and that something akin to Talcott Parson's (1902-1979) 'sick role' may have applied even then.

Even more ancient than this is the Homo Erectus Georgicus specimen referred to as the 'toothless old man' found at Dmanisi, Georgia.

However, he was not a 'man' in the modern sense. This specimen has been dated at around 1.8 million years BP making this species a possible ancestor of both humans and Neanderthals. This pre-human individual would also have needed the support of others in order to simply stay alive.

Throughout the whole of human history – and before – we have needed to call upon the assistance of others when it comes to our quality of life and our staying alive. That continues to be the case throughout the world today. Some people may be able to manage on their own to a considerable extent but this is relatively rare. It is not characteristic of the human species for individuals to live in complete isolation. Instead, we live in groups which offer mutual support.

Examples and lessons from other animals.

Pre-humans aside, there are also lessons to be learnt from observing other animals when they appear to be unwell. Here with the corollary that they might have something to teach us. For example, when unwell an animal's dietary habits often change. Furthermore, animals often 'self-medicate' by ingesting plants or minerals that they do not otherwise consume. Some animals demonstrate obvious geophagy – the eating of soil. This may perhaps seem odd until one remembers that we use preparations such as milk of magnesia as remedies for indigestion. This is a form of magnesium hydroxide which is a constituent of the mineral brucite.

Or that charcoal biscuits were once used to reduce flatulence or aid with stomach problems – and still are for dogs.

However, I want to take a more oblique approach when it comes to animals and ask to what is an animal responding when it adopts these atypical behaviours? Unable to look into the minds of other human beings this is not a question that is going to be easy to address in relation to animals. Indeed, it is not a question that many would even attempt to ask. However, one must conclude that there is surely some internal state or experience to which these animals are responding.

As the American philosopher Daniel Dennett (2006) puts it:

"Everything that moves needs something like a mind, to keep it out of harm's way and help it find the good things; even a lowly clam, which tends to stay in one place, has one of the key features of a mind – a harm-avoiding retreat of its feeding "foot" into its shell when something alarming is detected."

Something 'like a mind' does not necessarily imply something that thinks in the way that we think or evaluates its own awareness in the way we do. However, there clearly appears to be some sort of awareness that elicits such responses in all animals. While Dennett focusses upon the need for creatures to perceive and respond to external dangers, I am more concerned with their perception of internal ones. This 'something like a mind' is something that also registers the internal state of the organism.

Matthew Kluger at the University of Michigan Medical School has shown that when experimentally infected with aeromonas hydrophila, lizards sought out and basked in the warmer parts of their enclosures. Those prevented from doing this were more likely to die than those that were unrestricted. Unable to regulate their body temperatures physiologically, most lizards are unable to develop a fever in response to such infections. Instead, they must rely upon external sources of warmth. Kluger also did a similar experiment with fish with much the same findings. It follows that while fever may be unpleasant it is not necessarily a bad thing. It makes the body's internal environment less hospitable to invading pathogens.

The inner physical world of a lizard or a fish is one that can be probed scientifically via a number of laboratory techniques. The inner experiential world of a lizard or a fish is not one that we can interrogate or even imagine. Whatever it is like, it is sure to be less sophisticated than that of higher animals - not least the class Mammalia to which we belong. However, we should perhaps recognise that there are fundamental aspects of brain anatomy that are common to all vertebrates. These are the parts of the brain whose operation is fundamental to ensuring success in the struggle for life by monitoring internal states. These are the basic physiological operations which, while they do not require conscious processing for their execution, do nevertheless elicit certain types of behaviour that have survival value. In higher animals, such as ourselves, these behaviours are elicited in response to things experienced; such things we label as hunger, thirst, pain and also, I suggest, illness.

In biology, we study how bodies work in a rather mechanistic way. What we understandably overlook is that animals have an interior experiential world to which they respond. What we somehow forget is that we have an interior experiential world to which we respond. Such responses are not uncommonly survival-oriented.

The pre-requisites of individual survival in biological and medical perspective.

There are, I would like to suggest, three pre-requisites for success in the struggle for life. The first is a body that is operating in an orderly way physiologically: that there is a physical dimension. This would seem to go without saying. This is the focus of much of modern medical and related biological research. However, when I speak about 'order' or 'orderliness', I should point out that it is becoming evident that physiological order comes about not through precisely regulated steady internal states but through an ability to fluctuate - often in unpredictable ways. Order is not a case of simple, classical homeostasis but something more dynamic. What is necessary is a minimum of disorder or, what might be called, physiological entropy.

The second pre-requisite is that to which I have given particular attention today: how the body is represented; how it appears to the 'something-like-a-mind' within: what might be described as an experiential dimension. In human terms, this would include both the conscious and non-conscious parts of the mind. In order to continue to go about the business of surviving, one should be feeling well – or, at least, well enough. That is, there should be a minimum of experiential disturbance which would otherwise cause a distraction in the struggle for life.

The ideal situation is for a person to have a body that is operating in an orderly way and for that person to be feeling well. Barring accidents, such an individual has a greater chance of continued survival.

There is a third pre-requisite and that is the ability to interact with the environment in a way beneficial to survival: that there is what I shall call an interactional dimension to survival. These interactions are expressed through different forms of behaviour directed at obtaining food, drink, shelter etc. Even the grooming behaviours shown by ourselves and other animals fit into this category.

At times, through injury or disability, we may not be able to obtain from an otherwise abundant environment those things essential for our continued survival. Alternatively, there may be times when our environment may be lacking in those essentials. Either scenario, were it to last long enough, would compromise our chances of success in the struggle for life and potentially lead to our demise.

These three pre-requisites we might describe as a survival triad.

The WHO definition of health and the pre-requisites of survival

I noted earlier that definitions of health were hard to formulate. I also noted that the WHO definition was an object of criticism and that, although it may not be perfect it is nevertheless somewhat enduring. Its emphasis on various 'complete' forms of 'well-being', for example, is particularly problematic. However, I would like to suggest that it is not without some merit. I would like to suggest that it does, in the way in which it is set out, point to a possible way out of the current difficulty in defining health and disease. The WHO definition separates out different aspects or dimensions of an individual's struggle for life: physical, mental and social forms of 'well-being' are singled out for our attention. In so doing, they represent key facets of human life – and, indeed, animal life in general.

Success in the individual struggle for life, I have suggested, is a product of the three aforementioned pre-requisites. That being the case, we can ask whether it is possible to marry these to the three 'well-beings' of the WHO definition of health. My first pre-requisite in the struggle for life is the requirement for the orderly operation of the physical body in terms of a minimum of disorder. This seems to fit with the WHO’s 'physical well-being'.

My second pre-requisite related to how one felt. One might subsume the conscious and non-conscious experiential aspects of survival into the WHO's 'mental well-being'. I am here using 'mental' to mean something other than merely 'psychiatric'. One might think here in terms of a minimum of experiential disturbance. The third dimension, 'social well-being', is an odd one. It is difficult to know exactly what 'social well-being' might be. However, since one's environment includes other people from whom – as we have seen – help in the struggle for life can be obtained, I would like to suggest that interaction with all aspects of one's environment could constitute 'social well-being' and this form of being-in-the-world is included in the third pre-requisite. This may or may not seem to be stretching a point but I am comfortable in doing this.

The WHO definition of health, if it is to have lasting usefulness, should allow for a certain degree of re-interpretation without re-drafting. As new insights and interpretations become available, the meaning of words and phrases can shift subtly without losing their veracity.

While I have identified three pre-requisites for survival and related these to the WHO 'well-beings', it is the first two that I think provides a basis for defining health and disease. In a cooperative species such as our own, the need to interact with the environment to obtain our daily needs can be by-passed; those needs can be provided by somebody else on our behalf. However, for the first two pre-requisites to provide a basis for defining health and disease both pre-requisites must be considered together.

A person who both feels well and who has a body operating in an orderly way is in a state that may warrant being described as 'healthy'. Similarly, a person who both feels unwell and who has a body that is not operating in an orderly way is in a state that may warrant being described as 'unhealthy'; a disease state even. I am trying to tread carefully here. I do not what to get into the knottier issues of trying define health and disease but I do want to try to give some impression that it is in this direction that I believe such definitions may lie. Part of the problem why definitions of health and disease are hard to obtain is to do with what we have been focussing upon. Various thinkers have focussed upon the thing that is 'health' and tried to define that; others have focussed upon the thing that is 'disease' and tried to define that. Instead, we should, I believe, be focussing primarily upon that to which these words are applied: the individual. We should be exploring the different states individuals can have and be considering how the labels we have available might best be applied to those states. (By label I mean, of course, words like health, disease, well, unwell, ill etc.) This approach is the opposite to that which tends to be adopted.

Also, I want to raise the question of disability because I think there is something potentially helpful here. Using a statistical model of health and disease, the question of the status of blind people, deaf people and wheelchair users arises. Can they ever be deemed to be healthy? After all, they can never be deemed to be 'typical' or 'average' in the usual sense. The medical model would therefore seem to suggest that they are not healthy, yet it cannot bring itself to say so openly – not least because there would be something ridiculous about such an assertion.

As I said earlier, in a cooperative species such as our own, the need to interact with the environment to obtain our daily needs can be by-passed; those needs can be provided by somebody else on our behalf. The 'interaction' aspect of the survival triad separates the issue of disability from the other two aspects: the two that I just suggested should be considered together when trying to define health or disease. This separation means that disability – blindness, deafness, wheelchair use etc. – has no immediate bearing on how health and disease are each defined. So a disabled person can be deemed healthy or unhealthy for reasons quite separate from their disability. Thus a problem that the medical model has not been able to accommodate can be surmounted.

Thus, I believe that there is scope for addressing the question of defining health and also disease, via the biological notion of the struggle for life. It is certainly something that I believe warrants further investigation not least for the potential assistance it could give to the much criticised WHO definition. It may be possible to keep the current wording of the WHO definition of health but understand the words in slightly different more nuanced ways – perhaps along the lines I have suggested.

Post Script

I did not set out to deliberately contrive this parallel between the WHO's three 'well-beings' and what I am calling the survival triad. How I got to this particular idea I am not entirely sure. Except to say, of course, that it all began, you will remember, in the mid-1990s, when I was unable to find out what was meant by the phrase 'Degenerative Disease' as it appeared in the title of the module I was put upon to teach. You may be wondering if I ever did find out what it meant. Well, I can confidently say that I do know what 'degenerative disease' is – but only in the sense of what I was told when I did eventually talk to someone who had previously taught the module. It transpires that there was already a module called 'The Biology of Infectious Disease'. The module I was to teach was to include only non-infectious conditions. Having one module called 'The Biology of Infectious Disease' and another called 'The Biology of Non-Infectious Disease' might have caused confusion; the titles were deemed to be too similar. So the word 'degenerative' was chosen simply as an alternative to 'non-infectious'. This is interesting in itself because of what it implies about the thinking and presuppositions of those concerned and their assumptions about the notion of disease in particular. However, that is yet another story.