My first philosophical thought
The first part of my title refers to a famous line in Superman – not Nietzsche's Superman (or Übermensch), but the comic strip - when people looked up and couldn't quite make out what it was that was flying through the air. Based upon past experience, they tried to determine whether what they saw was a bird or a plane. In so doing, they were unable to reach the correct conclusion. It was, of course, Superman.
What the last part of my title refers to will become clearer shortly.
My topic is, in effect, about distinguishing between things and finding ways of doing so. To do this, I shall consider some personal reminiscences, some events from the news and draw together some well-known – and perhaps less well-known – philosophical problems that have certain similarities.
However, perhaps more than this, the job of any speaker to a philosophy club, as I see it, is to encourage thought. To that end, I shall try to leave open as many questions as possible and will try not to state what I think but point to what I am thinking about instead. Often, I find that there is a great deal to be learned from the way in which people (including philosophers) go about their thinking and how they go about formulating their questions. In this respect, there is nearly always something to be learned from somebody, even when one finds their field of interest to be of no relevance to one's own work.
So, let me begin with a question to think about. What is the earliest philosophical thought you can remember having?
This does not have to be the first overtly philosophical problem you heard about at school, or from reading a philosophy book, or from listening to a philosopher.
What I mean is what is the first thought you can remember that, in retrospect, can be described as philosophical? This, therefore, includes any thought that can be described as philosophical even though you may not have realized it to be philosophical at the time.
If I were to take a guess, most, if not all, of these thoughts would probably have been questions of some sort. Indeed, something that continues to puzzle me is where questions come from. It appears to be a puzzle of the same sort as the question 'Where do hypotheses come from?' – that is, how do we formulate our hunches about the ways in which the world works?
The first philosophical thought I can remember having must have occurred when I was about eight years old and was indeed a question. The age I was at the time is less vivid to me now than the thought itself and where I was at the time I thought it. It occurred while I was on a ship: HMS Victory. This is the most famous historical ship in Britain. It was Nelson's flagship at the Battle of Trafalgar. As a boy, I become interested in history and in Nelson in particular and my grandmother took me on a day trip all the way from London to Portsmouth just to see the Victory which was in dry dock.
As we toured the ship, we could see extensive restoration work to the hull being carried out down below us. At one point, the tour guide stopped and pointed down to this. He said that this would take another two years to complete and added that virtually every timber in the ship had been replaced since Nelson's day. As I understand it, the only timbers that still remain are situated where Nelson died and have taken on something of a sacred quality – perhaps because they are soaked in his blood. So it appears that nobody is willing for these to be ripped out and disposed of in the way so many of the other timbers have been.
From this, you can probably guess what my earliest remembered philosophical thought was: If all the timbers in this wooden ship have been replaced, can this still be the same ship?
Theseus's Ship
The example I have just given of HMS Victory's transformation over the last couple of centuries, may be familiar to many, if not all, of you as being much the same as the problem of Theseus's ship.
The story of Theseus's ship is quite well known from Greek legend.
According to Plutarch (46?-120 AD) the late first/early second century biographer:
'The ship wherein Theseus and the youth of Athens returned [from Crete] had thirty oars, and was preserved by the Athenians down even to the time of Demetrius Phalereus, for they took away the old planks as they decayed, putting in new and stronger timber in their place, insomuch that this ship became a standing example among the philosophers, for the logical question of things that grow; one side holding that the ship remained the same, and the other contending that it was not the same.'
So my earliest philosophical thought was not original; I was not the first to have thought my earliest remembered philosophical thought and I was certainly not the last to have had that thought in a British maritime context.
Cutty Sark
In the UK, the problem of Theseus's ship – although it wasn't referred to by that name – was a topic of popular interest for a few days at the end of May this year (2007).
On May 21st, we awoke to news that, during the night, a fire had started on board the Cutty Sark – which is probably the second most famous historical ship in Britain. So we quickly turned on the television and saw what appeared to be the whole ship ablaze.
The Cutty Sark used to bring tea to Britain in the nineteenth century so you can perhaps see why there is particular affection for this ship. Before the fire, it, like the Victory, was in dry dock (at Greenwich in London) and, like the Victory, was being used as a museum ship.
Although certain parts of the bow and stern were not completely destroyed by the fire and many timbers were being housed elsewhere for conservation work at the time of the fire, the problem in many people's minds was, if this ship were to be rebuilt using new timber - which the Trust in charge of the ship was promising to do even as it smouldered – then could it still be considered to be the same ship; was it still the Cutty Sark?
Significantly, the Cutty Sark fire occurred during the age of the internet, therefore, people were able to post blogs about it – not least, on the BBC News website – so that they could be read out on the radio. Some of the comments took a decidedly philosophical tone. Certainly, a more philosophical tone than one usually expects from such sources.
As a result, it became clear that a lot of people were asking essentially the same question. Indeed, that question, about whether or not a rebuilt Cutty Sark could really be the Cutty Sark, seems to have occurred spontaneously in the minds of a number of people as they heard the news over breakfast or on their way to work.
Indeed, it seems that the question of whether something really is or is not what it seems to be is something that concerns a lot of people and this event seems to have served as a spur and an outlet for such thinking. I can assure you that Britain is not full of professional philosophers waiting for something to write to the BBC about. Ordinary people are asking a very old and genuine philosophical question – even if they do not realise it. (This is how I believe it should be; philosophy is for all and sometimes the fewer technical terms the better.) But what is it about this problem that makes it so interesting? What is it about this problem that seems to bring out the latent philosopher in so many people?
Sadly, typical of the media, this topic quickly passed out of the news and the comments raised were literally left hanging in hyperspace. However, the next time the Cutty Sark is brought to people's attention – and certainly when the restored ship reopens to the public – the question of whether it really is the Cutty Sark is sure to be raised all over again.
So far, I have mentioned three ships and not one of them was the Wasa! However, this problem does not apply only to ships whose timbers are lost and replaced. A paradox which parallels that of Theseus's ship is the paradox of the heap or the sorites paradox (from the Greek σωρος (sōros) meaning heap).
Sorites – The paradox of the heap
The sorites paradox can be described in one of two ways.
The version that most closely parallels the problem of Theseus's ship suggests that we consider a heap of sand. From that heap, let us take away one grain of sand. For want of one grain of sand, the heap will still be a heap, so let us take away another grain of sand and so on, over and over again. At what point does the heap cease to be a heap? Or, to return to our original problem, after the removal of how much timber did Theseus's ship cease to be Theseus's ship? (If, indeed, it did cease to be Theseus's ship.)
Alternatively, we could describe the sorites problem this way: consider taking a grain of sand and dropping it onto an empty flat surface. That one grain of sand does not make a heap. Now if one drops a second grain, that still does not make a heap – even in the unlikely event of the second grain coming to rest on top of the first. But if one were to continue dropping individual grains of sand over and over again, a heap would eventually form – but at what point can it be said to become a heap?
(This is perhaps my second earliest remembered philosophical thought because, as a boy, I used to love playing with my grandmother's eggtimer and watching the grains of sand build up into a heap as they dropped from the full into the empty chamber.)
There is, potentially a third version of this problem, that I think is just begging to be asked – but I have never heard it presented in this way. It is this: starting with a heap of sand, take one grain away and then drop that grain of sand onto an empty flat surface. The heap is still a heap and the single grain of sand is still just a single grain of sand. Continue this process over and over again. At what point does the original heap disappear? And at what point does the new heap form? And do both of these events occur at the same moment or can the quality of 'heap-ness' be in two places at once when one is using the same source material?
Other versions of this problem
Before we move on, let us briefly note some other versions of these problems to see what they might offer us.
John Locke's Sock
The early English empiricist, John Locke (1632-1704) had his own version of these problems.
What if you have a sock that gets a hole in it? Would it still be the same sock if one were to put a patch on it?
Indeed, one could ask – although I am not aware whether Locke ever did – would it be the same sock if one simply sewed up the hole with thread? There is now thread added to the sock and sewing up the hole will have changed the configuration of the original fibres around where the hole had been. So here, two different types of alteration have been made.
Locke went further. What if one wore the sock for many years, repairing it over and over again, to the point where no material from the original sock was left and it was completely replaced by patches - can that be said to be the same sock?
Trigger's Broom
Some years ago, a popular British television comedy series used a version of our core problem. In this series, there was a character called Trigger. He got this name because he looked like a horse and Trigger was the name of the horse owned by Roy Rogers, the singing cowboy. All this, in many respects, sums up the character who was a rather dim-witted road sweeper who often made rather puzzling remarks.
One day, in a café, he tells his friends that when he started out as a road sweeper, he was given some very good advice which he has always followed and that was 'Always look after your broom'.
So he has. He has looked after the same broom for 20 years and had just been given a medal by the council in recognition of the fact. However, he tells his friends that in the process of looking after that broom for all those years, he has had to replace the handle 14 times and the brush 17 times! 'So how can it be the same broom?' his friends ask. But, Trigger is adamant; it is the same broom. He even has a photograph to prove it.
The writer of the comedy has borrowed from a philosophical problem called the problem of my grandfather's axe. (Although I have also heard it referred to as the problem of my grandmother's axe.) In this problem, my grandfather had an axe which he passed on to his son (my father). My father had to replace the handle because it was damaged. Eventually, he passed the axe on to me, his son. I have had to replace the head because it was damaged. If the axe has changed both its handle and its head, is it still the same axe?
The reason for providing these different versions of the same fundamental problem is that sometimes the conclusion one leans towards in response to one version is different to that one might lean towards in response to another version. For example, how one resolves in one's own mind the problem of Theseus's ship – with its hundreds of components – may not be the same as how one resolves the problem of Trigger's broom (or my grandfather's axe) being made of only two components. Would those philosophers to whom Plutarch refers, who held that the ship remained the same, have said the same of Trigger's broom (or my grandfather's axe) – or even John Locke's sock?
A re-reading of the problem
These stories are usually seen as illustrating the philosophical problem of identity. In particular, identity of substance. In fact, inherent in this problem is not only the notion of identity of substance but also that of the continuity of the same substance through time. Despite the apparently light-hearted nature of the stories I have given, a very real set of hard-to-crack philosophical questions lurks just below the surface.
However, instead of using these problems to consider the question of identity of substance, I would like to focus instead on something else these problems might be used to explore and that is what might be called 'recognisability of things'. This idea of 'recognisability of things' concerns not the continuity of substance but the continuity of the relationship between components even though these may change over time. 'Recognisability of things' may also have a bearing on how we formulate our hypotheses about the ways in which the world works and, indeed, how we formulate all sorts of questions.
The substance of the present HMS Victory is not continuous in every detail with the substance it had in the past. Only a few timbers of those there two hundred years ago remain. On that level, it is not the same ship. However, during the last two hundred years, there has always been a single object that has been continuously recognizable as being HMS Victory. The parts may have been changed but the outward shape of those parts and the relationship those parts had and continue to have with each other while forming part of the ship as a whole has always remained recognizably the same. If we look at old paintings and photographs of the Victory, we can recognize the same object. It has always been recognizable as a late eighteenth/early nineteenth century wooden warship; it has not been gradually transformed, as parts have needed replacing, into an aircraft carrier, for example. So, on that level, it is still the Victory.
Here, instead of substance, I am emphasising 'structural relationship' because it is the 'structural relationship' displayed by an object that we recognize – not its substance.
I want to go one step further with this idea of recognisability. This can be illustrated using the story of Pavlov's dogs.
Pavlov's Dogs
The story of Pavlov's dogs is well-known. To put it very briefly, when fed, laboratory dogs were also exposed to the sound of a ringing bell. The two events became associated in the dogs' minds such that when the bell rang, the dogs would begin to salivate in expectation of being fed even when food was, in fact, withheld.
At least, this is the way most people know and remember the story.
However, Pavlov's experiments went further than this. As well as conditioning his dogs to expect food at the sound of a bell, in two other separate experiments, he was also able to condition dogs to associate feeding with the sound of a metronome (ticking at a specific rate) and to associate feeding with the sight of a circle. Thus, when they heard a specific metronome beat or when they were shown the circle, the dogs started to salivate in expectation of being fed. Furthermore, when the metronome was set to a quite different beat or the circle was replaced by an ellipse, and the dogs were not fed, they learned to associate this with the withholding of food and so did not salivate.
(Indeed, in the ten days I have been here, I have, to some extent, become conditioned to crossing or not crossing the road in response to what is essentially a metronome beat at pedestrian crossings.)
What Pavlov did next was, I think, the sign of an elegant experimenter. He exposed dogs conditioned to the two metronome beats to a third beat at a different rate; somewhere between the first two. Similarly, the dogs conditioned to seeing the circle and the ellipse were exposed to a shape that was somewhere between the circle and the ellipse. In both experiments, the dogs were unable to determine precisely what the stimuli meant. They couldn't decide whether they were going to be fed or not.
(Indeed, while trying to cross some roads here, I too have been confused by which ticker I should be listening to.)
As I understand it, the dogs demonstrated some form of psychotic behaviour and had some form of nervous breakdown.
(I'm pleased to say that, so far, I have been able to get across the road without exhibiting any signs of mental illness.)
Here, I wonder if we see dogs going about a form of questioning. This is not a form of questioning of the sort we usually recognize – we put our questions into words. Rather, we perhaps see something of the mental unrest that often precedes the formation of worded questions.
Thus, it appears that the problems we are considering are not confined to humans; the problem of the 'recognisability of things' is not just a philosophical problem for stimulating discussion. It appears to matter to other animals – or at least dogs. I must admit that, perhaps, I may be stretching a point here but then again, perhaps I am not. Perhaps I am recognizing something that others don't; or perhaps I am 'over-recognizing' – if there is such as thing.
While we humans have come to see this as a philosophical problem – and have given it different names and provided a number of different scenarios in order to illustrate and explore various aspects thereof – perhaps there is something more basic to the animal psyche which we share that is in need of consideration.
If, what is for us an intellectual problem is something experienced by dogs, then perhaps it is more than just a philosophical problem for the likes of ourselves to enjoy discussing. Perhaps there is a practical dimension which somehow influences the way we live; perhaps it even influences our ability to survive in the world.
Consider the practical problem of when fruit is ripe. Some berries change colour from green to red; bananas change from green to yellow. When they are no longer green, each is ready to be eaten without any ill effects. Speaking as somebody who is red-green colour blind, this can be a problem for me. When I come to pick berries or choose a banana, the problems we have been considering this evening take on a certain practical significance.
Why this matters to a (this) biologist
There is one famous version of the problems we have been thinking about that I have not mentioned so far. This concerns Heraclitus and the river. The problem of Heraclitus and the river is often summed up in the question 'Can you step into the same river twice?' meaning if you step into a particular body of flowing water on two separate occasions, is it the same river on both of those occasions? However, Heraclitus did not confine himself to being concerned about just the river; he was also concerned about the person who stepped in. One modern translation states "No man ever steps into the same river twice, for it is not the same river and he is not the same man."
Heraclitus was perhaps more accurate than he could ever have realized. It is now known that different parts of our bodies are constantly being replaced. Furthermore, this occurs at different rates in different tissues.
The average life span of a red blood cell, for example, is about 120 days. That means that our red cells are replaced about three times a year. Even the different parts of Trigger's broom didn't need replacing at that rate.
Indeed, there has been some interesting scientific work done at the Karolinska Institute in Stockholm which suggests that the average age of the cells in our bodies may only be between about 7 and 10 years. While there appear to be some brain cells that are not replaced, the general finding is that virtually all our other body cells are replaced more than once – sometimes several times – during our life span. However, while there is very little of the substance of that eight year old boy that went with his grandmother to see the Victory all those years ago remaining in the body before you this evening, nevertheless it somehow claims continuity with him. Indeed, consisting of substance aged only between about 7 to 10 years, why don't I still look like that eight year old? What is it that has aged since it is not my substance?
I still remember the tee-shirt I wore that day. What if I had continued to wear it, enlarging and patching it, like Locke's sock, as it wore out? Although I claim continuity with my eight year old self – which has been enlarged and replaced a number of times – could one think the same of a tee-shirt that had gone through the same process?
We are like the Victory in that our substance has been largely replaced and that more than once. However, while the parts have changed the 'structural relationships' between those parts has been more constant. For example, my doctor still puts his stethoscope on the same places when listening to my heart and lungs.
One reason why the problems we have been discussing matter to me as a biologist is that I believe that there is something lacking in modern biology; something so lacking that most biologists do not even notice that it is not there.
Currently, there is no thoroughly worked out theory of the organism as a single, unified entity. (By organism, I mean each one of us as a distinct, individual, biological object.) We have learned how to take the organism to pieces and see what is going on inside but we do not have a way of fully integrating this knowledge back together again so as to understand how these components contribute to the whole as a complex system. The finding that different cells and tissues are being turned over at different rates and that physical continuity is only an illusion is important for forming such a theory; it must take into consideration the fact that what continuity we have is not based entirely upon substance. Furthermore, this means that any theory of the organism cannot be based on substance alone.
As a science, biology is perhaps the youngest in the modern sense – at least, the youngest of the three umbrella sciences – the other two being physics and chemistry. Indeed, the word Biology only dates from about 1802. There are, of course, much younger sub-disciplines within all three main sciences. However, we sometimes forget that while new questions are formulated and explored via these new sub-disciplines, some of the older questions get side lined, go out of fashion and may even be forgotten about altogether. One of the earliest questions it was hoped that biology would be able to answer was 'What is life?' This was a question biology largely inherited from broader philosophical debate. It seems to have been left to biology to solve this question but biology, finding it too hard to crack, has let it slip down to the bottom of the pile of pressing questions.
In his book 'Mere Christianity' (p225) the British writer CS Lewis noted "… what I proudly call 'Myself' becomes merely the meeting place for trains of events which I never started and which I cannot stop." This may be what our physical bodies are like: meeting places for processes that merely use substances which continuously make entrances and exits.
Increasingly, I find myself drawn to the idea of organisms – human and otherwise – as systems which exhibit an overall biological state. As material enters and leaves, as energy flows through that system, it constantly changes. I am different now compared with when I woke up this morning; I am different now compared with when I entered this room less than an hour ago. In fact, I am different now compared with when I started this sentence. And yet, within this change, something persists; something is still recognizable even if it cannot be said to be identical with how it was at a former moment in time.
Thus, the problems with which I began are not merely interesting mind games. Indeed, for me, that is not what philosophy is about; that would be to denigrate its potential to provide genuine contributions to human thought. Although they are old and the way they are usually presented rather quaint, the problems we have been considering this evening may, nevertheless, have something valuable to offer. These problems are potential sources of new insight.
I once read a cynical remark which stated that 'Philosophers exist to engage in logical analysis and that is all.' This echoes Karl Marx, in his Theses on Feuerbach where he stated that 'Philosophers have only interpreted the world in various ways; the point is to change it.'
The problem of Theseus's ship, the sorites paradox and other related problems can be investigated for the pleasure of the challenges they offer the thinker. They can be investigated for purposes of writing a paper and enhancing one's academic reputation. Or they can be investigated for practical reasons – literally to change the world by adding to the ways in which we see and understand that world, ourselves and the relationship between the two.
To explore different problems, philosophers often devise stories or scenarios via which they can test their ideas and develop new questions. Sometimes it is useful to draw inspiration from a completely different field of human expression. Sometimes it is useful to take a diversion that some might consider bizarre.
When considering an organism, I might ask 'Is the meaning of a piece of music the whole piece or the sum of the parts?' and then see what the answer to that question might suggest if applied to the organism. I might then ask 'How much can be taken away from a piece of music before it loses it meaning?' and apply that answer. One might also ask 'What about the meaning of a sentence?' And so on.
To that end, there are sure to be new versions of the problems we have been considering this evening waiting to be formulated. So let me finish with one such attempt.
The unscrupulous art gallery attendant
We might call this the problem of the unscrupulous art gallery attendant.
Consider an art gallery displaying modern art.
For simplicity, I have in mind the Tate Modern in London and a particular work: Carl Andre's Equivalent VIII. First constructed in 1966, this piece of work consists of 120 firebricks arranged in two ten-by-six layers on top of each other.
At the gallery, there is an attendant who, when nobody is looking, takes one of the bricks and immediately replaces it with one that looks exactly the same. The next day, he swaps another brick, and so on. At home, he gradually reassembles the bricks he takes each day in exactly the same order in which they appeared in the gallery. Eventually, all the bricks are swapped. At home, the attendant is then tempted to move them around a bit, make different shapes with them, add to them, subtract from them, mix them with other bricks that look the same, mix them with other bricks that are quite different. One can go on.
At each step, one can insert any number of different questions about what this does to the original piece.
As I understand it, part of what the artist wanted Equivalent VIII to do was to ask of the viewer questions about equivalence. There are, in fact, other Equivalents made from the same number of bricks, only they are arranged in different ways. Equivalent VIII happens to be the last in the series. So I can perhaps claim to be treating Equivalent VIII in the spirit in which it was intended – if not more so.
So, in this spirit, I can perhaps think of Equivalent VIII as any number of objects whose unity or nature I am concerned about. This might be a whole organism built out of different brick-like components; or it may be one of an organism's brick-like components made out of its own brick-like sub-components. The bricks may be used to represent different things such as organs, cells, genes etc.
There was a question that was topical just before I left Britain. It concerned the licensing, for the first time, of a technique for merging human and cow cells to form embryonic stem cells that could be used to treat nerve injuries, Parkinson's disease etc. The immediate reaction of some people in Britain to this news was outrage. This time, when they submitted blogs, they did not adopt the philosophical tone I mentioned earlier. Instead, many seemed to have equated this procedure with the formation of some sort of half-man, half-cow hybrid – even though the proportions were clearly not 50:50 and developing a full-grown creature was certainly out of the question. However, what if they had stopped and applied the problem of the unscrupulous art gallery attendant to this question – what might they have been able to draw from this?
I shall leave this as an open question – not least because I haven't thought it through fully enough either.
Ending
However, to reach new and better ways of understanding, we often need hypothetical problems that can lead us out of our ordinary thought world and into another. Problems such as those I have considered this evening, I believe, can help. Fortunately, one does not have to be Superman to do this – or even a philosopher – a child of eight could do it.
All those years ago, I could not have imagined the lasting significance that a chance thought during a day trip to see an old ship could have. That trip with my grandmother to see the Victory was a great success. In fact, we repeated it a year or two later – if, indeed, you can make the same trip twice.