Saturday, March 31, 2012

Essays on free will, qualia and spectrum inversion

To: Gordon F.
From: Geoffrey Klempner
Subject: Essays on free will, qualia and spectrum inversion
Date: 22 May 2007 12:13

Dear Gordon,

Thank you for your emails of 12 and 18 May, with your essays for units 10-12 of Philosophy of Mind.

I will respond under each essay title.

'Summarize the argument that free will is impossible, whether on the assumption of determinism, or on the assumption of indeterminism. Do you see any loopholes that the defender of free will might exploit?'

You propose two ways of resisting this argument. First, we should give up 'either-or' thinking, and secondly that we should 'start thinking in terms of interactions rather than actions.'

Both of these proposals look initially attractive. Let's start with 'either-or' thinking.

A good question to ask about discussions of 'free will' is what sort of 'free will' we want. This is basically what Galen Strawson seems to be doing. We do in fact attribute responsibility to agents, and find some point in doing so. Yet, at the same time, there seems to be a sense in which no-one is 'ultimately responsible'. So, is this a case where philosophers define a notion of 'free will' which is useful for practical purposes (in other words, the strategy of 'compatibilism') while recognizing the ultimate (and ultimately terrible) metaphysical fact that no-one is 'really' free?

Once again, we seem to be faced with an 'either-or'. Is it practical freedom that interests you, or metaphysical freedom. Decide!

One possible way to unravel this would be to recognize, as Strawson does, the absurdity of the idea that one should 'want' metaphysical freedom. The clearer idea we have of such a notion, the more absurd it becomes. On the other hand, the more that we look at the 'practical' notion of freedom, the more subtle it becomes, and the less it appears a mere makeshift, or 'second best'.

In other words, the compatibilist would say, there is no 'either-or'. We arrive at the correct view of the reality human freedom by both routes - by revealing the absurdity of metaphysical freedom, and by articulating the notions of freedom and responsibility as these are actually applied.

Should we start thinking in terms of interactions rather than actions?

The difficulty I have with this is in seeing why the standard view of cause and effect cannot be applied to interactions. There is no degree of complexity at which the notion of cause and effect breaks down. What there is are systems where it is impossible to identify 'causes' and 'effects' because too many things are going on at once. In other words, all that's needed here is recognition of the limits of human knowledge in the light of, e.g., chaos theory. The master argument against free will does not require that real life systems be analysable into causes and effects. Determinism says that given the state of a system at a given time, only one sequence of events from that moment on is physically possible. Never mind how those events are generated.

What is true and important, is that to be an agent is to be involved in a constant process of 'making oneself'. We are, therefore, responsible not only for what we do on a given occasion but also for being the persons that we are because of all the decisions we have made in the past.

'Define a 'quale', giving some examples of qualia. What is the philosophical interest of the notion of a quale?'

My argument, 'we are not given A and B' is intended as a straightforward rejection of qualia. There are no such things. The attempt to 'identify' qualia or 'raw feels' with physical processes is misguided because it assumes the very thing that the materialist needs to reject, the notion of a 'logically private object', in Wittgenstein's sense.

There are no qualia, in the sense of 'logically private objects'. However, I am fully prepared to accept that there is an irreducible 'idiosyncrasy' in the way that people perceive which can never be eliminated by any amount of discussion or experimentation. This is not because 'no-one can see my private object' but for more subtle reasons: the story that one can tell about another individual's mental state is inexhaustible.

You can open a book and read every word, cover to cover. But human beings are not books, even when we think we can 'read someone like a book'. There is always room for surprises. The language which we use to describe our mental states to one another exists because of a large degree of commonalty in the way that we think and feel. But this is merely the backdrop to the recognition of each person's uniqueness.

It is not as if I know exactly how things are for me but I can only give you an approximation. I don't know myself, at least, not in the sense that I can say. If I could say, then you would know too, because I could tell you. We are as inexhaustible to ourselves as we are to others.

'Explore the philosophical issues that arise out of the thought experiment of spectrum inversion.'

I had a great deal of trouble with the part of the program which discusses spectrum inversion. As a matter of fact, this was a question which came up in the very last examinations which I sat, back in 1976 in Oxford, when I took my B.Phil.

We want to say that there are empirical conditions which would lead us to judge that two persons A and B call the same object 'red' while at the same time each sees the object as having a different colour.

There are various possible scenarios. For example, a drug which makes a human being's colour spectrum undergo an inversion. The individual who has been given this drug judges that a UK post box 'looks blue' and a US post box 'looks red'. In time the individual learns, or re-learns, the English vocabulary of colour words, and eventually is able to make colour judgements with sufficient proficiency that one would never know that, for that person, the colour scheme of the world has completely altered.

Let's assume that the way that the drug works is not a mystery, but that we can trace the permanently crossed connections in the retinal nerve and brain which result from taking the drug.

So far, so good. But what if this wasn't a drug, which only effects the individual who takes the drug, but some kind of genetic manipulation so that the crossed connections are passed to that person's offspring. Do we want to say that they also see the world differently from those who have not had the genetic treatment?

I am essentially following the same line as in unit 11 part (b). In relation to a given definition of 'normal' colour perception, or 'normal' circumstances under which the colours of objects are perceived we can define states which are 'abnormal' in various ways. Yet, in time, the abnormal becomes normal. It is very hard to accept that whether a subject's perception is 'normal' or not is not an all-or-nothing matter. There is no either-or, no cut-off point. Hence the attraction of qualia - which must, nevertheless, be resisted.

All the best,


Friday, March 30, 2012

Free will incompatible with determinism and indeterminism

To: Jeremy C.
From: Geoffrey Klempner
Subject: Free will incompatible with determinism and indeterminism
Date: 22 May 2007 11:09

Dear Jeremy,

Thank you for your email of 14 May, with your first essay for Possible World Machine, in response to the question, 'Examine the claims that ‘freedom of the will’ is incompatible with determinism and also incompatible with indeterminism.'

There is good work here, despite your complaint about having to compress the essay to 800 words!

We need first to sort out exactly what the compatibilist claims. As you say, Hume was a compatibilist. Hume viewed our belief in the uniformity of nature as a mere hypothesis, and our ability to judge 'causes' and 'effects' as limited by what we have so far been able to observe. A causal statement is true if it holds universally - at all times and places, but such a statement can never be conclusively verified. As for the belief in a 'connection' between cause and effect, that is just bad metaphysics. No such connection has been or ever will be observed.

This might make it look as if what the compatibilist requires is a 'softer' view of causation, but that appearance is misleading. Hume's argument is that our interest in free will extends just as far as the question of what an agent may be held 'responsible' for, and that this trains our focus on actions which arise from due deliberation, not done under external duress etc. etc. If that argument is good, then it applies to the 'hardest' determinist. If I complain about the bad quality of your essay, or praise you for a great piece of work, either way my interest is in you. It is completely irrelevant that, things being the way they are, you had to write, word for word, the essay that you did write.

You mention Van Inwagen's description of compatibilism as a 'wretched subterfuge'. I would have liked to have seen a bit more in defence of that claim. My view would be sympathetic to Van Inwagen, in that compatibilist 'freedom' leaves the perceived problem of free will exactly where it was to start with. You can't define a problem out of existence as the compatibilists seem to want to do.

Indeterminism, as understood in the essay title, is not the view that there are no causes and effects, which would indeed lead to a world 'based on pure chance and randomness'. The situation would be in fact worse, because, as Kant effectively argued, there can be no objective world if we can't identify causal regularities (Strawson in 'The Bounds of Sense' argues that Kant's attempted 'transcendental deduction' of the law of determinism should be understood this way, allowing for the possibility of a moderate degree of indeterminism, very much against Kant's own intentions.)

The problem with the (moderate) indeterminist view was pointed out by Hume: if we attribute any aspect of an agent's decision to indeterminist 'wobble' in the physical world, then to that extent the decision is random and therefore not attributable to the agent's character or the quality of the agent's deliberations.

There is an article by David Wiggins in the Honderich collection 'Essays on Freedom of Action' (Routledge) which questions that argument but Wiggins fails to offer any third alternative. I have yet to see a convincing case.

The closest one comes, as you seem to hold, is in the thought that maybe dualism is true after all, and our decisions do not have a physical causal basis but rather arise autonomously, from our non-physical mind. The problem I have with this is that the only advantage such a supposition has is its obscurity. As Hume observed, our decisions spring from our character and the quality of our decision making. The further one pursues the question, 'Why did you do that?' the more reasons one finds why the agent, being the kind of person that he was had to do what he did. And if not, then praise or blame are irrelevant because the final decision, good or bad, can only have arisen as a result of finely tipping the mental balance one way or another - something which we may 'praise' or 'blame' the agent for, while all the while recognizing that it is ultimately a matter of moral luck how such finely balanced decisions are resolved.

As you can see, it is very difficult to get away from this 'either-or' model. That was the point of the essay. Yet I have a residual sympathy for Wiggins. There is something fishy here. I can't put my finger on it. Perhaps the fishiness is a result of our relying on a 'mechanical' model of human decision making, where our character and the considerations that occur to us, our weighing reasons and deciding are so many 'pushes' and 'pulls' in the decision making machine. But, then, what is the alternative?

All the best,


Thursday, March 29, 2012

Difficulties in the way of a materialist view of the mind

To: Christopher J.
From: Geoffrey Klempner
Subject: Difficulties in the way of a materialist view of the mind
Date: 22 May 2007 10:09

Dear Chris,

Thank you for your email of 14 May, with your first essay for the Possible World Machine, in response to the question, 'What difficulties stand in the way of a materialist view of the mind, according to which thoughts, feelings and sensations are nothing more than processes in the brain?'

This is a very good piece of work which contains one completely novel argument (or, at least, novel to me) namely, your explanation of a possible source of resistance to materialism in the fact that even the most 'beautiful mind' is housed in a 'walnut shaped lump'. I have never thought about this before. How would one evaluate such a claim?

One way would be to conduct a thought experiment. Suppose that we are opening a human being's skull for the very first time. How would a brain have to look (i.e., how beautiful) in order to overcome our prejudices against materialism? What do you imagine? All I can think of is something that looks incredibly intricate, like the most exquisite piece of jewellery, with twinkly flashing lights - in fact the kind of thing that you get in sci-fi films about androids. (But then, of course, when we look at brain in a microscope all the beauty and intricacy is revealed - at least, so someone who has sufficient knowledge to understand what they are looking at.)

Another possibility is that when we open a person's skull we see - a beautiful face (or an ugly face, if the person is evil). What is more beautiful than a beautiful face, or more apt for being the seat of consciousness?

Another argument which you lay considerable stress on concerns the limits of empirical knowledge. Just as we cannot be certain that all swans are white, on the basis that all the swans we have so far observed are white, so we cannot be certain that (what exactly?) on the basis that all brains we have so far observed lack (what exactly?).

You can see the difficulty I have with this. There is a real possibility, given our lack of knowledge at the present time, that the brain is not a Dennett style super-computer but merely a relay mechanism - just as Descartes believed - which responds to a non-observable input, translating these impulses into neuron firings. Suppose we were to discover this. Would that prove Cartesian dualism? In the scenario which I am envisioning, neuroscientists and physicists agree that there exists a force which cannot be detected by any physical instruments that they have been able to construct, whose only effects are on a functioning brain. In a nod to philosophy, they attribute this force to 'soul substance'.

But it is not Descartes' soul. The problem is that Descartes' argument for mind-body dualism can be run with whatever science discovers about our objective nature. Empirically postulated soul substance is invisible, so the 'ugly brain' problem does not arise. Yet we still have to deal with the Cartesian intuition that I would know that I exist and have consciousness, even if an evil demon was deceiving me into thinking that there existed a world of objects in space, and therefore that what I am essentially cannot be identical with anything belonging to that world.

I recognized your argument from paragraph two as Frank Jackson's notorious 'Mary' argument. There is more on this argument in Samuel Michaelides' fellowship dissertation which you will find in the Pathways Essays Archive

You also try out David Chalmers' zombie argument. Having read his recent interview in Philosophy Pathways I have begun to wonder whether Chalmers really wants a non-physical soul-entity, or is merely objecting to attempts at psycho-physical reduction. In paragraph one, you talk of 'physical processes which can be subject to empirical analysis'. This is Dennett territory: mapping out the 'program' of the human brain. But there is another possibility - that the way the brain realizes mental states turns out to be indecipherable by any physical process - short of duplicating the complexity of that very brain. Why should we assume that if materialism is true, then it will be possible at some time - however far in the future you like - to 'read' the contents of a brain from observation of its physical states?

On a 'connectionist' view of the nature of the brain, there is no brain program but only a continually refined adjustment amongst the billions of neurons. There is just one way to 'access' the contents of a brain, and that is to be the individual whose brain it is. (I explore this possibility in my piece, 'Truth and subjective knowledge' In other words, you can be a kind of materialist ('soft materialist' sounds like a good term, by contrast with your 'hard materialist') while admitting that there will always be an 'explanatory gap'. What gives one the right to call oneself 'materialist' would be general arguments establishing that the brain is capable of 'realizing' the phenomena of consciousness while at the same time admitting that we will never be in a position to explain how specific patterns realized in matter are related to the quality of a person's mental life.

All the best,


Wednesday, March 28, 2012

Philosophical significance of the paradox of the Heap

To: Victoria M.
From: Geoffrey Klempner
Subject: Philosophical significance of the paradox of the Heap
Date: 18 May 2007 11:04

Dear Victoria,

Thank you for your email of 13 May, with your first essay for the Philosophy of Language program, in response to the question, 'How would you explain to a non-philosopher the philosophical significance of the paradox of the Heap?'

This is a good essay which shows a keen awareness of the importance of the problem of vagueness for the philosophy of language. As you say, logic itself, 'one of the key tools to meaning and definitions of philosophical truths' is put into question by the paradox of the Heap.

The key questions are the nature of logic and the notion of truth which is assumed when we define a sound argument as one which never leads from true premisses to a false conclusion, and also (as you again point out) our conception of the relation between the view of the world filtered by our language, and the objective nature of reality.

The logical principle involved is that of 'mathematical induction'. This is arguably the most important principle in maths. Basically, a general proposition of the form, (x)(Ax) or, 'All numbers x have the property A' is proved if you can show:

(1) A is true of the number 1.

(2) If A is true of x, then A is true of x+1.

The principle assumes that we have a domain (in this case the domain of natural numbers) and a way of ordering the domain (in this case by the simple function, 'add 1').

The Heap paradox can be run in both directions, as you show. In fact, these are perfectly symmetrical so far as the logic, and the conclusion is concerned. So let's take the case were we start with one grain.

(1') One grain of sand is not a heap.

(2') If x grains of sand is not sufficient for a heap then x+1 grains of sand is not sufficient for a heap.

Therefore, there is no number of grains sufficient for a heap.

The premisses are true, the conclusion is false. Therefore, it seems, we have to reject the principle of mathematical induction. Or do we?

This would be a catastrophe. With one sweep, virtually all of number theory would be eliminated.

Now, one looks around for alternative solutions. This is the point where we cheerfully hand the problem over to the non-philosopher (or the sceptic about the usefulness of philosophy) and say, 'You try!'

Generally, when non-philosophers respond sceptically to an alleged philosophical paradox, there is in fact a picture in their minds which they are clinging onto, a half-articulated 'theory', which they have never thought to question.

Here's one typical response: 'All you've done is show that there aren't any 'heaps' in reality. 'Heap' is just a rough and ready term which serves a useful purpose, but in principle we could count the number of grains and describe the precise geometrical shape of the so-called 'heap', and that would give all the facts, the literal and unvarnished truth about the object in question.'

What is wrong with that response? One can point out that a large part of our ordinary, everyday vocabulary is vague in one respect or another. In which case, it would seem to follow that in ordinary conversation, we do not succeed in 'describing reality'. When I say, 'There is a heap of sand on the front drive,' I am not saying anything true. In order to say something true, I would have to use terms which had no dimension of vagueness.

'OK,' says our respondent, 'in that case I'm not interested in the 'literal and unvarnished truth' but merely in 'pragmatic truth', saying things that we can generally agree about without getting too fussed about precise details.'

You can point out that this escape from the paradox is purchased at a great cost. So far as the things that we talk about everyday are concerned, there is no 'truth' or 'falsity', but only 'what works', or, maybe only, 'what serves to convince'. All the noble and principled views that we take about the importance of truth crumble into dust. There is no difference between 'truth' and 'lies', only different degrees of lying.

- I'm just imagining how the dialogue might go. I was once at a dinner at my college in Oxford (University College) where there were a number of fellows sitting round the table - History, Law, Philosophy. One History fellow asked one of the Philosophy fellows, 'Are you still working on the topic of proper names? I've never understood why it's such a problem saying what a proper name is!' The Philosophy guy tried and failed. It seemed that they had had this conversation before. This incident has stuck in my mind as a perfect illustration of how difficult it is to get across, even to very intelligent non-philosophers, why a philosophical problem or paradox is perceived as 'important'.

Once you get the philosophical point - whether we are talking about vagueness or proper names or whatever - you realize that every response is a 'theory', even the response which rejects (seemingly rejects) the problem as trivial. There is no way out. Hence the various attempts to deal with the problem of vagueness described in the program (which are outside the scope of this essay). The beauty of paradoxes in philosophy is that they force us to respond, in one way or another. And sometimes none of the responses work and we are left in a state which the Greeks called, 'aporia'.

All the best,


Tuesday, March 27, 2012

Science versus myth: the relevance of Thales

To: Gerard M.
From: Geoffrey Klempner
Subject: Science versus myth: the relevance of Thales
Date: 15 May 2007 11:53

Dear Gerard,

Thank you for your email of 9 May, with your essay for the Ancient Philosophy program, in the form of a fictional letter written by Thales to philosophers today, which I read as an answer to either, or both, of the questions, 'What does the examination of the arguments and theories of the first philosophers show us about the nature of philosophy?', and, 'The possibility of a physical explanation of the nature of the world and how it came to be was a philosophical discovery.'

You said that you battled to reduce the length of the essay from 3000 words, but it takes nearly two pages to get to the point: 'Your difficulty is that societies have always lived in and through the imagination but you are unaware that your cosmology, or, of you prefer, the conditions of symbolisms have changed. In a sense, then, you are as enslaved to myth as much as the people of the antique world.'

And one sentence later, the essay ends!

I would loved to have seen an answer to that question. In what sense do we inhabit a mythical world today, and what would it be like - or what would it be - to emancipate ourselves from that myth by means of reason and logic? how can logic help with our contemporary predicament?

There are various ways in which one can draw parallels. It is arguable that school education is doing a worse job today, compared with the relatively recent past, of equipping young people with a basic general knowledge - through history, geography, science etc. We are breeding generations of specialists: language teachers who are totally at sea with the most basic concepts of science, science teachers who are ignorant of geography, geography teachers who are clueless about history.

Combine scientific illiteracy with the pace of technological change and innovation and you have people whose attitudes to the tools that they daily use are just like the pre-philosophical ancients to the phenomena of the physical world.

An IT consultant wrote to me last week asking what I had to say about the theory that aliens who look like humans are living in our midst. I replied that anything is possible, but in order to have any relevance to what we believe, a theory must be testable. If an IT system goes wrong, you formulate hypotheses and test them. She wrote back yesterday insisting that people were 'closing their eyes' to the possibility of aliens living in our midst. Either the woman is paranoid (which I have to allow is a possibility) or she has managed to get a so-called 'education' without acquiring any sense at all of what science is and what it is for.

Here is one test you can perform to discover a person's 'common sense' physics. A stone is tied to a piece of string which the subject whirls around. The string breaks. What happens next? The three most popular answers are:

(a) The stone continues to go round in wider and wider circles.

(b) The stone continues in the direction in which it was moving when the string broke.

(c) The stone shoots straight out in whichever direction the string was pointing when it broke.

It has been over three hundred years since Newton. Shouldn't every educated person know the correct answer?

(Clue: think about how you aim a sling.)

Another aspect of the way reality has been 'fictionalized' can be seen in the rise of computer games, and the total dominance of screen entertainment. In the 'old' days, you went to the cinema to see a 'show'. You left the everyday world and entered a dark room to enjoy the magic light show. There was never any doubt where the real world ended and the world of the 'silver screen' began.

Now, we have portals in every room which are rapidly replacing windows as our view on the world. Much has been written about this, of course, by contemporary philosophers of culture. You can look up the French philosopher Baudrillard who has much to say on this phenomenon.

More than ever before, we are dependent on so-called 'experts', whose knowledge so far exceeds ours that they could just as well be priests. And many experts behave just as if that were true. This brings us back to the theme of education, and the question what can be done to remedy the situation.

I think we are both agreed that a good dose of philosophy would make a difference. Philosophy should be on every school curriculum. It should be impossible to get an education without being aware of the question what knowledge is and what it is for, how we decide in matters of belief, and most important of all the individual person's responsibility for the beliefs that he or she holds.

All the best,


Monday, March 26, 2012

Materialism vs immaterialism and the role of physics

To: David Y.
From: Geoffrey Klempner
Subject: Materialism vs immaterialism and the role of physics
Date: 15 May 2007 11:05

Dear David,

Thank you for your email of 7 May, with your fourth essay for the Metaphysics program in response to the question, 'What is matter? Does the physicist's account of the nature of matter have a significant role to play in the philosophical dispute between the materialist and the immaterialist?', and your email of 15 May with your notes in response to unit 13.

I want to start with an interesting speculation that you make, of a 'parallel world... in which the predominant Realism of the time was based on the objective existence of an X', where the term X refers to something which is not 'matter'.

In response, I'm tempted to quip something along the lines of Mr Spock, 'It's matter Jim, but not as we know it.'

It's one thing to say that matter might be very different in its ultimate physical structure in some other possible world and quite another to say that there might be a possible world where there was no matter but something else, an X, instead.

Descartes defined the essence of the concept matter in terms of extension and in doing so he was partly right. 'Matter' is a concept which goes along with the concept of space. However, as Leibniz argued, the concept of an 'occupier of space' fails to capture what we really mean by 'occupy'. Descartes envisages three dimensional volumes where various qualities are exemplified. Leibniz's response is that so far no reason has been given why volumes cannot overlap. What is it for a given volume to be 'impenetrable' by another? The missing aspect is that of 'force'. It is a priori true that that which occupies space exerts a force preventing other space occupiers from occupying the same space.

Imagine a computer game where all the objects, including yourself, have the capacity to pass through other objects at will. There has to be some rules which explain why things move or do not move, or how any object can act on any other (do you have a gun? how do you hold it? how can the plasma bursts hit anything?).

In this sense, 'matter' may be defined in Leibnizian (later, Schopenhaurian) terms as 'space occupier that exerts a force'. This isn't a very informative definition. We don't want to rule out a priori that some things can 'overlap' (or maybe we do - as David Wiggins has argued on the basis of his concept of a 'criterion of identity' but that's another story).

Enough of that, you get the gist.

Berkeley was hostile to the notion of hypothetico-deductive explanation (and therefore to Newtonian 'corpuscles') in a way which is not explained by his immaterialism. Your argument brings this out. There is no reason, in principle, why the immaterialist should not avail himself of the (pragmatically) best available notion of 'best explanation' of the phenomena.

The real difference between the materialist and immaterialist comes down to this: for the metaphysical materialist, physics gives the ultimate account of what is (filtered, of course, through the dialectic). Whereas, for the immaterialist, the physical account is merely the 'best theory of the phenomena', which is ultimately true in virtue of the existence of something which cannot be described in physical terms - God's mind, or monads, or noumena, or the Absolute. For the immaterialist, there is necessarily more to say rather than (as one might first think) less.

Unit 13

First, I have to tell you that for most of my time as a graduate student, the term 'dialectic' was a magic word for me. It was the most important notion in my (admittedly limited) philosophical vocabulary. My exemplars were the later Wittgenstein (in Philosophical Investigations), Bradley's Appearance and Reality, and the second section of Kant's Critique of Pure Reason (the Dialectic of Pure Reason). I struggled with Hegel but found the bits I understood inspiring, especially in the 'Science of Logic' which is mind-blowing by any standard.

As you have perceived, dialectic is the key to this program. I don't really have a lot to say about what you have written because you have 'got it'.

In the unit I didn't mention Leibniz's argument from the beginning of the Monadology, that whatever ultimately exists cannot have 'parts' divisible ad infinitum and therefore cannot be matter. This is an interesting argument in itself which seems altogether to bypass the issues that we have been considering. No need to start with egocentrism and its negation, or the nature of perception and the problem of the external world. Matter can't be real. The only other thing given in our experience is experience itself. Therefore 'perceptions' must constitute the ultimate reality.

Where is the flaw in Leibniz's argument? is there any?

Regarding mysticism, it should hardly be surprising that Hegel follows a route similar to the Gnostics. He was well aware of the connection and with the connection with Plotinus who holds a not altogether dissimilar doctrine - having written encyclopaedic 'Lectures on the History of Philosophy' (a great second-hand catch if you can find it, three volumes translated by Haldane and Simpson). Look up, 'Hegel Plotinus Gnostics' in Google and you will find a rich selection of references. Hegel was also aware of the connection with Indian philosophy.

But, of course, the fact that disparate thinkers have followed the same route is what you would expect - from the dialectic.

All the best,


Sunday, March 25, 2012

Why must others count in my deliberations?

To: Frank Z.
From: Geoffrey Klempner
Subject: Why must others count in my deliberations?
Date: 15 May 2007 09:46

Dear Frank,

Thank you for your email of 6 May, with your third essay for the Moral Philosophy program, in response to the question, 'Why must others count in my deliberations?'

Your essay raises several difficult issues that need to be untangled. However, I am actually not sure where you stand on the question of acts which are not required by duty in response to a recognized right, such as giving to charity or helping someone even though that person has no 'right' to our help.

So before I go into the more complex arguments, consider the following scenario. There is a beggar who regularly walks the streets near your office. You have had several encounters with this thoroughly unpleasant person who won't take No for an answer and curses you when you refuse (rightly in your view) to give anything. One day, as you are walking to work, you notice the beggar importuning some other hapless pedestrian when the beggar falls to the ground. Approaching closer, you can see the clear signs of a heart attack (you once did a course in first aid). The other pedestrians walk hurriedly by. You can easily do the same, and allow this man to die thus getting rid of a persistent nuisance, or you can call an ambulance on your mobile phone. Without hesitation, you call. Is this proof that the beggar has a right to life, or to be aided by you? Yet the difference between the case of the beggar and other persons whose lives we are able to save is only one of degree - a degree of distance and of the effort or cost of the action to ourselves.

I'll leave you to think about that.

The first strand we need to unravel is the question of what follows from the rejection of solipsism. I have argued that there are two alternatives: anti-solipsism and the theory of two worlds. According to anti-solipsism the only coherent moral standpoint is one of 'detachment'. This leads, by one route, to the ethics of utilitarianism and the strict requirement that we should take into account the needs of every conscious being in the universe. Similarly, from the point of view of the Kantian Categorical Imperative the only important question is the 'right thing to be done' regardless of the moral agent's own interests.

On the alternative, two worlds view, my obligations vary with the distance of others from me, although ultimately every individual 'counts for something and not nothing'. This is the basis of the view that one's obligations towards one's friends and family are stronger than towards people who you don't know. My greatest obligations are towards myself.

The argument for the two worlds view is that recognition of the reality of others - and consequently their moral claims - is a necessary condition for there being a world for me. This is a controversial claim. However, a similar view has been argued by the Continental philosopher Emmanuel Levinas who bases his ethics on the ultimate asymmetry of self and other rather than, as in the disinterested view, on their ultimate symmetry. (Levinas' magnum opus is 'Totality and Infinity'.) Levinas is a difficult thinker, especially for English readers relying on translations. However, his basic premise - the absolute 'otherness of the other' - is not so difficult to grasp. My respect for another is based not on recognition that he is basically 'the same' as me, but rather on the fact that he has an aspect which is beyond my possible knowledge. Each of us is however in a similar situation in that we are situated beings, whose view of the world is necessarily from a perspective, by contrast with a hypothetical God's 'view from nowhere'.

In the Analytic tradition, the argument that our obligations are not towards everybody equally has been forcibly put by Bernard Williams (see B. Williams and J.C.C. Smart 'Utilitarianism For and Against' Routledge). I have a lot of sympathy with Williams' view. He develops his case, not from a metaphysical standpoint but rather with the help of intuitive examples which emphasise the importance of a sense of 'personal integrity' and a one's attachment to one's projects and values.

I therefore don't agree with you that the reason why others count in a person's deliberations is the one given by psychological egoism, but agree (for different reasons) that the 'I' is important, and for this reason my family, my friends, my society, my country. The elements that define our values and who we are cannot be removed from the equation without rendering life pointless. As the American business philosopher Tibor Machan recently quoted to me, 'We are here on earth to do good for others. What the others are here for, I don't know' (W.H. Auden).

All the best,


Saturday, March 24, 2012

Analysing talk of 'the will' from a philosophical standpoint

To: Gordon F.
From: Geoffrey Klempner
Subject: Analysing talk of 'the will' from a philosophical standpoint
Date: 11 May 2007 11:36

Dear Gordon,

Thank you for your email of 3 May, with your essay for units 7-9 of the Philosophy of Mind program in response to the question, 'Describe a variety of situations in which one would naturally talk of 'the will'. How is such talk to be analysed from a philosophical standpoint? Does your analysis show that we are right (or wrong) to think and talk of 'the will' in the way that we do?'

I'll start with the will.

Hitler believed in the power of his will and the will of the Reich as many before him, who have succumbed to the temptation of thinking oneself as 'destined' to succeed no matter what. Strength of will and belief in destiny won't help you if you are unlucky enough to be in the way of a stray flying bullet from a police shoot-out, or a car careering out of control while its driver has a heart attack.

Nietzsche believes in 'the will' and was a materialist, at least ostensibly. That should make one question whether talk of the will implies a non-material power. However, Nietzsche was a materialist only in the sense that he rejected mind-body dualism. In The Will To Power he describes a metaphysical theory where entities are identified and described, not in terms of what 'stuff' they are, as in materialism, but rather in terms of that entity's perspective on the universe, insofar as it strives to exert itself in opposition to things that oppose it. The clearest 'demonstration' of this is biological phenomena, but as this is a metaphysical theory, the same is true in principle of a pebble.

In some respects this is like Leibniz's theory of monads, but with action and striving substituted for the monad's essential property of perceiving the universe from a unique point of view. In other respects, the theory is very reminiscent of Aristotle's theory of matter and form. To be a man, is to strive to realize one's human potential, as each individual 'substance' does in its own way.

It is an empirically attested fact that some people have more 'will power' than others. Aristotle would explain this in terms of cultivated habits. However, in notable contrast with Kant, the best sort of man for Aristotle is one who is naturally inclined to do the right thing, rather than the one who has to struggle to contain his immoral impulses. You need will power when your instincts and inclinations rebel and you call upon your practised ability to suppress them. The 'continent' man is thus second best to the 'moral' man.

Some students just love books and don't need any incentive to study. Others need to psych themselves up, and talk of 'will power' (or 'bottom power' as I've sometimes heard this described). As it happens, I fell into the latter category.

The explanation offered here is empirical and naturalistic, rather than metaphysical.

Your wife's explanation makes perfect sense to me. Things might have been otherwise, in which case she would have found herself mentally going through the kind of process that Aristotle's 'continent man' goes through.

Your dialogue

We can discount the worry that by catching the bus in the nick of time, I am indirectly responsible for the accident which would not have occurred had the bus started off 20 seconds before it did actually start. It is, of course, a source of wonder that each of us exerts an incalculable influence on the train of the world's events. Who is to say that some minor decision by postman in Tokyo might not have been responsible for 9/11 through a chain of causes and effects like Lorenz's butterfly?

The description of why the young man enlisted is typical of the situation which we find ourselves in when we make an important decision which we are responsible for. Everything that I am and have come to be can only be accounted for in two ways: the things that have happened to me since my birth and the decisions I have made. Much of this one cannot see. Characters are formed, people make good decisions or wicked decisions, are heroes or cowards, and one cannot always predict who or why or when.

We are expected to be able to give reasons for our actions. I would argue that every action is done for a 'reason' in this sense and that there is no meaningful distinction between reason and emotion or inclination. Yet reasons do come to an end. At some point one has explained all that it is within one's power to explain. All one can say is, 'I just felt that it was the right thing to do.'

All the best,


Friday, March 23, 2012

Aristotle's case for the priority of substance

To: Pearl K.
From: Geoffrey Klempner
Subject: Aristotle's case for the priority of substance
Date: 9 May 2007

Dear Sachiko,

Thank you for your second email of 9 May with your University of London essay in response to the question, 'Does Aristotle have any good reason for saying that substances are prior to items in other categories?'

You've said not a word more than needs to be said, so far as expounding Aristotle's basic doctrine goes. However, there are two directions in which this essay could be expanded.

The first (as you might have guessed from my boring insistence on interrogating the question) is to ask what Aristotle means by 'prior'. Prior, in what sense?

I can think of several kinds of priority (in no particular order): explanatory priority (you have to explain A in order to explain B as the explanation of A is part of the explanation of B); ontological priority (B exists only in virtue of the existence of A, without A, B could not exist); definitional priority (the definition of A is a component of the definition of B); maybe some vaguer notion of importance or interest (A is more important/ interesting than B) - OK we can discount that. But you get the idea.

Maybe it's obvious to you what kind of priority Aristotle means, but in going through the possibilities you will show the examiner that you know and hopefully write a better essay.

Suppose that Aristotle means ontological priority. Substances are ontologically prior to other items because the other items only exist in virtue of the existence of substances. Of course, if you are being difficult you could say that by the same argument substances only exist in virtue of the existence of qualities, in the sense that there can't be a substance without qualities any more than there can be a quality without a substance to be predicable of.

But this does seem to be along the right lines. Here is where we get to the second way in which the essay could be expanded. In recent times, there has been a strong revival of interest in Aristotle's distinctions. The original 'locus classicus' is the book 'Individuals' by the Oxford philosopher P.F. Strawson, a ground-breaking work came out in 1959.

In 'Individuals' Strawson says he is engaged in 'descriptive metaphysics' which he contrasts with 'revisionary metaphysics'. Descriptive metaphysics aims to lay bare the structure of our conceptual scheme. Aristotle was a descriptive metaphysician in Strawson's view. Revisionary metaphysics, by contrast, tries to show that our common sense understanding of the world as made up of individual things with qualities, occupying space and time is ultimately incorrect - mere 'appearance' - and that in reality the world is, e.g. 'windowless monads' (Leibniz), or a conglomeration of events and processes (Whitehead), or fleeting phenomena (Hume).

Strawson argues for the thesis that spatio-temporal particulars are the basic individuals. The criterion for 'basic' is in terms of the notion of a 'criterion of identity'. We can't say how many whites or how much white there are in the room but we can count the white things. The identification of 'white' depends upon the identification of white things (spatio-temporal particulars).

In the course of his argument, Strawson offers refutations of Leibniz's theory, as well as the theory that a complete description of the world could consist in identifying 'features' at 'places' without first identifying spatio-temporal particulars.

A spatio-temporal particular is Aristotle's 'primary substance'.

Spatio-temporal particulars change over time, while preserving their identity. This aspect is taken up by David Wiggins (originally in his monograph 'Identity and Spatio-Temporal Continuity' and later in his book 'Sameness and Substance'). The identity of spatio-temporal particular is always identity 'under a covering sortal concept'. The old man drinking the hemlock is the 'same man' as the youngster who played in the yard under his mother's watchful eye. As Wiggins argued, a thing cannot undergo unlimited change. The Biblical story of Lot's wife turning into a pillar of salt is incoherent, because there is no covering sortal concept under which one can identify, first a female human being, and then a pillar of salt. There is no logical difference between Lot's wife 'turning into' a pillar of salt and being instantaneously annihilated and replaced by a pillar of salt.

A sortal concept is Aristotle's 'secondary substance'.

These contemporary arguments add to Aristotle and are not merely expositions of his theory. However, it could be argued that they are fully Aristotelian in spirit (if we ignore the point I made in my comments on your essay on the four causes: Wiggins in fact goes on to offer a theory of how unobservable structures are part of the notion of a sortal concept, which is very un-Aristotelian).

Of all Aristotle's doctrines (so far as I can think, at this moment anyway) the doctrine of primary and secondary substance, and the claim of the priority of spatio-temporal particulars is the most enduring, and is taken as the starting point for contemporary excursions into metaphysics.

All the best,


Thursday, March 22, 2012

Essay on Aristotle's four 'causes'

To: Pearl K.
From: Geoffrey Klempner
Subject: Essay on Aristotle's four 'causes'
Date: 9 May 2007 12:03

Dear Sachiko,

Thank you for your email of 9 April, with your University of London essay in response to the question, 'In what sense of 'cause' do Aristotle's four causes deserve the name?'

The essay is good so far as it goes, and keeps well to the question. However, your inkling that something is missing is correct.

You are right, of course, to point out that 'cause' is merely our translation of Aristotle's 'aitia' so the question whether Aristotle's four causes 'deserve' the name is really a question one would direct at the translator rather than at Aristotle himself. And yet, there is a point in asking *how much* is explained (regardless of what term we use) by each of the 'causes', as there is a very significant difference between Aristotle's view and the view that a scientist would take today.

So far as the classification and your explanation of it goes, a reader might think that Aristotle has merely added three dimensions of explanation to our common (I won't say Humean because not everyone agrees with Hume's analysis) notion of efficient cause.

In fact, Aristotle's view of how things are explained is markedly in contrast with the modern view, which is, however much closer to what the Greek atomists believed (although still a considerable distance away).

The structure of your essay, therefore, should reflect this contrast. The way to do this is by first explaining how we might today make sense of Aristotle's 'causes' and then contrast Aristotle's considerably more meatier notion of formal and final cause.

Why did Joe's laptop catch fire? Because (material cause) it's made of plastic. (Mine won't because it's aluminium.) There was a short circuit (efficient cause) and sparks caused the plastic to ignite. But actually, it was a 'booby-trapped laptop' (formal cause) designed by the CIA to spontaneously combust (final cause) after it has been running for more than fifteen minutes.

Aristotle can agree with all this. But there is much that he would not accept. (OK, sorry, plastic is a bad example given that plastic wasn't invented then.) Why does plastic burn? Why does wood burn? Why doesn't water burn? Why doesn't ash burn? If you asked a modern chemist (or a Greek atomist) and Aristotle you would get very different answers.

The atomist will tell you that plastic and wood have an invisible structure which we can't see, but which accounts for its observable properties, as well as its ability to interact with other substances or respond to various kinds of treatment (heat, cold, electricity etc.) We all take completely for granted the idea that we can't see everything, that some explanations require the postulation of invisible structures.

The point of postulating invisible structures is to vastly simplify the set of scientific laws which we appeal to in giving explanations. You can hardly do serious science, if all you do is note down the various things that happen under various circumstances, which is basically all that Aristotelian 'science' amounts to.

Aristotle would have none of this. He refuses to accept that explanation must be brought down to the level of invisible structures and proposes instead a model of explanation according to which things do what they do because they are the kinds of things that they are.

Wood burns because it is wood, and wood is the kind of thing that has the potential to burn. End of explanation. If you want to ask why there is such a thing as wood in the universe, well that's a different question.

Aristotelian explanation is necessarily conceived from the point of view of a cosmos which ultimately has an irreducible teleological element - something the atomists sought to get rid of. Thus formal and teleological explanation are closely linked for Aristotle in a way that they would not be regarded today.

There are two explanations that one can give of this. First, the atomist theory was put forward as metaphysics and as such had serious flaws which Aristotle points out in his criticisms of Leucippus and Democritus.

However, secondly, Aristotle was convinced that human reason is adequate for understanding the natural world and the cosmos, in the sense that nothing required for understanding is hidden from our view. So, had the atomist theory been put forward in the spirit of an empirical theory (which, historically, it wasn't) Aristotle would still have objected on the grounds that it required the postulation of something that could not, in principle, be verified by observation. The contemporary notion of 'best explanation' or the hypothetico-deductive model is one that Aristotle would not recognize as a fully satisfactory approach.

I have a reference for this which you might not be aware of: Aristotle's piece 'On Generation and Corruption' which has some passages which are relevant to the points that I have made above. The text can be downloaded from It's too late to read the piece now (although it is not very long if you just wanted to flick through and search for juicy bits). It's something to mention when you contrast Aristotle's model of explanation of change with that of the atomists.

All the best,


Wednesday, March 21, 2012

Role of Aristotle's God - the unmoved mover

To: Pearl K.
From: Geoffrey Klempner
Subject: Role of Aristotle's God: the unmoved mover
Date: 9 May 2007 10:30

Dear Sachiko,

Thank you for your email of 8 May, with your University of London essay in response to the question, ‘What is the role of Aristotle’s God? Is he explanatory of anything?’

A good, clear essay, at least so far as it demonstrates knowledge and reasonably good understanding of Aristotle’s unmoved mover argument.

A point that I have been trying to get across is that you must respond to the exact wording of the question. The examiner always has a motive for composing the question in a particular way.

‘What is the role of Aristotle’s God?’ That’s a funny question to ask, in itself. Do Gods have roles? what does that mean? Then the examiner helpfully suggests one possibility, ‘Is he explanatory of anything?’

Well, that’s one role - or is it? Aristotle distinguishes four ‘causes’, formal, efficient, final and material. Each cause ‘explains’ in a different way. So, for Aristotle, we would expect to find three explanatory roles for God rather than one: as formal, efficient and final cause. (We can rule out material cause which might be true of Spinoza but not Aristotle.)

How good is the argument for an unmoved mover? One obvious objection that comes to mind, given that Aristotle has allowed an infinite series A, B, C... of one thing ‘moving’ another is why we can’t just project the series back to infinity? This is an issue that comes up with discussions of the cosmological argument for the existence of God. Just say, ‘things have always moved’ and leave it at that. No need for anything to start things off.

Aristotle would reply that insofar as we are talking about efficient causation, to say that C moved because of B, and B moved because of A, and A moved because of... to infinity is not to give ANY explanation but merely to postpone the explanation to infinity. Just as if you were looking at a beautiful chandelier hanging on a chain extending up into the clouds, and you asked, ‘What is the chain attached to?’ and received the reply, ‘The chain is not attached to anything, it just goes up for ever!’

In the Metaphysics, Aristotle defines his subject as the study of ‘being qua being’ and also as ‘theology’. The study of ultimate being is the study of God. This looks, potentially, like another role for God as the ultimate subject matter of our inquiry, rather than merely some explanatory principle. God is all we are interested in: philosophy starts in wonder and ends in God.

But this is a philosopher’s God, rather than the God of religious belief. God is the ultimate explanatory principle of the universe. On second thoughts, God is good, ‘an object of love and desire’ as you say in your essay. How on earth did that come about? How do you get goodness out of the unmoved mover argument? Why can’t the unmoved mover be bad, or just indifferent to good or bad?

This is something the examiner wants to know (as I read the question). We naturally assume that God is worthy of worship by definition. That’s just how the ‘God’ word is used. But if you are approaching from a philosophical angle this is something that needs to be proved. (It would be OK to briefly mention Xenophanes, as he raises the question of what makes a god or gods worthy of worship and answers that there can only be one such God.)

The answer, so far as goodness is concerned, is that by definition when one chooses, the object of one’s choice is presented as ‘good’. This is even true of a masochist who finds it ‘good’ to be whipped or a satanist who finds it ‘good’ to behave in a way which others call ‘evil’. By being the ultimate good, God provides the ultimate teleological principle for all goal directed behaviour.

Plato in the Republic talks about the ultimate form of the Good. In the Timaeus he describes the myth of a ‘demiurge’. But that is so far as he goes in describing anything remotely resembling God. Aristotle goes considerably further. Yet this is still a long way from the entity that the theologian would recognize today as a personal God. Aristotle’s God has no trace of personality, does not intervene in the world through wonders and miracles, does not reward or punish, and for all its ‘goodness’ remains sublimely indifferent to what actually goes on here below.

All the best,


Tuesday, March 20, 2012

Interactionist dualism versus epiphenomenal dualism

To: Gordon F.
From: Geoffrey Klempner
Subject: Interactionist dualism versus epiphenomenal dualism
Date: 3 May 2007 12:10

Dear Gordon,

Thank you for your email of 28 April, with your essay for units 7-9 of the Philosophy of Mind program in response to the question, 'Contrast the main features of interactionist and epiphenomenalist versions of mind-body dualism,' and your response to my comments on your previous essay.

Interactionist and epiphenomenal dualism

One has to distinguish the notion of mind or soul in popular belief or, possibly, 'folk psychology' from the way these notions appear in the more sophisticated philosophical views represented by the interactionist and epiphenomenalist.

In popular belief, the mind or soul is 'contained' in the body. If materialism is true, and the mind is in some sense identical with a brain, then this belief turns out, literally, to be true. There might even be the possibility of taking the mind (brain) out of its container (body) and putting it in another container (a brain in a vat, or a brain, or rather, body transplant).

When Descartes sneers in Meditation 1 about the idea of the soul as a 'wind or vapour' he is thinking of the picture of literal containment. This is the sort of thing which spiritualists believe (hence photographs of 'ectoplasm'). Whereas in Cartesian dualism -- as in epiphenomenalism -- the mind/ soul is not conceived as itself located in space. The connection with body is purely through causation, either two-way, or one-way.

What is the specific difficulty with epiphenomenalism? why wasn't Descartes an epiphenomenalist?

You say that, 'it does look like an epiphenomenal point of view leads to difficulties that a container point of view doesn't. If only someone could find an object in a body which most everyone would agree is a mind!'

I'm not sure if you see the same difficulty with interactionism. But here's an argument for saying that the two theories are not the same in this respect.

Descartes believed that all non-human behaviour is physically caused, a sophisticated variety of clockwork (the technology of the day). If he had existed in the 20th century he might have embraced the AI view of non-human 'intelligence'.

If taking an angel's-eye standpoint one could somehow follow through all the causal connections in a non-human brain, there are no gaps, no unexpected events. Whereas human brains are different. Something weird goes on in the pineal gland. Impulses go in, and impulses come out, but nothing that occurs inside the pineal glad explains how the output is related to the input. That is because there is, in fact, a second input from the individual's non-physical soul.

In this sense, it is true that one can 'find' the interactionist's non-physical mind -- through the recognition that something is absent. Whereas with epiphenomenalism, the entire process proceeds in exactly the same way whether non-physical events are produced or not. Hence the zombie hypothesis. By hypothesis, my zombie double would write the very same words that I am writing to you now.

Contemporary dualists tend to be epiphenomenalists, since this is the only real possibility consistent with what we know about the way the brain works. Descartes wasn't in a position to know this, but would have rejected epiphenomenalism outright because it fails to defend the 'soul' of religious belief: not determined by physical causes, capable of surviving the death of the body and so on.

Further discussion of personal identity

Some philosophers have questioned the coherence of the idea of identity over time. So let's define 'GF' as an ordered series of momentary person stages connected by a suitably defined relation of spatio-temporal and psychological continuity.

When duplication occurs, the ordered series branches into two ordered series. Logically, we are free to describe the situation was one where two ordered series overlap, say, [a, b, c, d] and [a, b, e f], or as one where there one partially ordered set containing a, b, c, d, e and f.

I claim that this redescription adds nothing, nor does it take anything away from the original description in terms of identity over time. The criterion of spatio-temporal continuity under the covering sortal 'person', may be viewed as a 'criterion of identity over time', or merely as the rule for constructing the ordered set of person stages, if you do not accept the notion of identity over time.

Saying that there 'always were' two persons is mere logical stipulation. I don't see that this raises any problem of predestination. It seems odd that one can, by conducting a duplication, 'bring about' a state of affairs in the past. But, again, we are not really going against any basic understanding of causality. What is 'changed' in the past is not any actual events, but merely the way we describe those events in retrospect.

Psychological continuity is not the same as personal identity. In terms of the redescription as ordered series of person stages, there are ordered series which meet the conditions for psychological continuity but not for identity. The 'rule' of psychological continuity is less demanding than the one which is equivalent to a 'criterion of identity over time'.

Of course, this raises the question (as the Methuselah thought experiment is intended to do) whether any coherent account of a 'criterion of identity' can be given.

I am not seeking to establish that there are 'personal identities which are necessarily preserved over time' but merely that it is OK (contra Parfit) to believe in personal identity, to regard one's own personal identity as significant and not merely an illusion. Parfit sees the question as all-or-nothing. My preference is for a more pragmatic view.

All the best,


Monday, March 19, 2012

Do possible worlds account for our notion of possibility?

To: Pearl K.
From: Geoffrey Klempner
Subject: Do possible worlds account for our notion of possibility?
Date: 2 May 2012 13:43

Dear Sachiko,

Thank you for your email of 2 May with your University of London essay in response to the question, 'In order to understand what a possible world is, we have to first understand the notion of possibility. So, we cannot use possible worlds to explain possibility.' Discuss.

If you're interested, and still have time, you can look at the last chapter (18) of my book 'Naive Metaphysics' (downloadable from which has some reflections on the similarity of Lewises indexical account of possibility/ actuality with the 'I-ness of I' and 'nowness of now'. More of that in a minute.

The notion of possible worlds only gets to do real philosophical work when we are looking at the truth conditions for subjunctive and counterfactual conditionals. This is what interested David Lewis. You could say something briefly about this.

It's only when we start defining similarity relations between possible worlds that the notion of possible world is doing real philosophical work, as opposed to merely being an interesting notational variant for box and diamond, or a 'model' for modal logic if you are into such things (I believe it was Kripke in an early paper on the semantics of modal logic who was responsible for resuscitating Leibniz's notion of possible worlds).

What is relevant to this question?

You allude to the debate between David Lewis who holds that S's counterpart exists in other possible worlds but not S, and Saul Kripke (see 'Naming and Necessity' -- I think that was the name you were fishing for) who holds that it is S, not S's counterpart who S thinks of when she considers 'what might have happened, if'.

You might think that you can't hold Kripke's view and still embrace Lewises strongly realist account of possible worlds. I'm not so sure. Kripke, in effect, gives a method for determining the 'essential properties' of an object. This is what we appeal to when we distinguish between 'rigid' and 'non-rigid' designators. However, we can perfectly well define a notion of 'transworld identity' using Lewises theory using the following definition:

S in w is transworld-identical to S' in w' if and only if S and S' have the same essential properties.

My interest in S', and S'' and S''' and so on is based on my interest in anyone who shares S's essential properties. That's just what I mean by 'S' in counterfactual situations.

OK, you say, S and S' are still 'different'! But the reply is that G today is in a sense 'different' from G yesterday. In response to someone who denied the logical coherence of personal identity over time -- i.e. someone who insists that the person you and I refer to as 'G' is merely a series of similar person-stages -- we can define a notion of identity as a class of person-stages which are *sufficiently* similar according to criterion C, whatever C may be. C turns out to be none other than the necessary and sufficient conditions for personal identity as held by a philosopher who DOES accept the coherence of the notion of personal identity over time.

Similarly, there may be no 'transworld identity' in the strict sense, but we can always define one, using a suitable criterion.

In other words, I don't think the issue between Lewis and Kripke over transworld identity is a big deal. It's a war of words. It is also a side-issue so far as the topic of this essay is concerned.

Put bluntly, the objection is that on Lewises view, there is no such thing as possibility. All so-called 'possible worlds' actually exist. The only difference is one of perspective (just as, the only difference between 'I' as used by you and 'I' as used by me is one of perspective, or, the only difference between 'now' uttered today and 'now' uttered yesterday is one of perspective).

Two things here. First, Lewis still owes us an account of why we 'take an interest' in other possible worlds. No explanation is needed why I take an interest in other subjects (S, David Lewis) and other times (yesterday, the day I was born). But what are other Lewis-style possible worlds to me?

What if I'd failed my Kant exam? Then today, G might be on some photography assignment somewhere and Pathways would never have existed. Why is that interesting? Because in some possible worlds (the ones most similar to the actual world, where G's counterpart fails the Kant exam) that's what actually happens. Thank God! (or, What a shame!).

The onus is on someone who accuses Lewis of not explaining the notion of possibility to come up with a reason why that explanation is not fully sufficient.

The other point is more 'metaphysical'. Why are we on this world? what makes this world so special? From Lewises standpoint, that's just like asking, 'Why am I, I?', or even more mind-bogglingly, 'Why is the time now?' I just am. It just is. There's nothing more to say.

Good luck!


Sunday, March 18, 2012

Locke on primary and secondary qualities

To: Pearl K.
From: Geoffrey Klempner
Subject: Locke on primary and secondary qualities
Date: 2 May 2007 11:24

Dear Sachiko,

Thank you for your email of 1 May, with your University of London essay in response to the question, 'What grounds did Locke give for drawing a distinction between primary and secondary qualities? Do they provide an adequate basis for doing so?'

On the whole, this is a good, clear account of Locke's theory. I have an objection, however, to one of the criticisms that you make of Locke's theory. Also, there is an important criticism which you have not discussed.

Locke believed in the corpuscular theory, and uses this to explain the distinction between primary and secondary qualities. However, he makes clear in Book I that he is not in the business of defending any particular physical theory. There is no philosophical 'proof' of the corpuscular hypothesis. It is just a hypothesis, nothing more.

So, whatever arguments Locke puts forward for the distinction between primary and secondary qualities must be such as to stand up to scrutiny even if we are doubtful about the corpuscular theory.

On Locke's view, all that the philosopher, investigating the concept of primary and secondary qualities can say is that the primary properties of an object - solidity, extension, figure, motion and number - must account in some way for the occurrence of secondary qualities, and this is a matter about which we are free to put forward hypotheses. But ultimately, this is something which is beyond our knowledge.

At one point in his Essay, Locke considers the possibility that angels might be able to 'see' the corpuscles which constitute the structure of matter. Today, we have electronic microscopes. However, a point which Locke perhaps did not appreciate sufficiently is the possibility of positing unobservable entities in the spirit of 'hypothetico-deductive explanation'. It is not necessary to be able to 'see' the smallest constituents of matter in order to have well founded reasons for believing that they exist, namely, that they provide the 'best explanation' of observable phenomena.

However, this is a digression. Locke's arguments for the primary/ secondary quality distinction do not in fact depend on the corpuscular hypothesis. That red is a secondary quality, for example, is shown by the fact that nothing happens to a rose when you turn off the light. It is still physically the same object. But it's redness is gone. That shows that the property of redness is only the capacity of the rose to affect subjects who possess suitable sensory organs, i.e. a secondary quality.

Pain is special case, however. You give Locke's argument that pain is not a property of steel. However, there is a clear difference between the case of pain and red. The rose IS red. Redness is one of its secondary qualities. But we would not say that the steel blade 'is pain'. Why not? What is the difference?

The most well-known criticism of Locke's primary/ secondary quality distinction is the one made by Berkeley. According to Berkeley, the reasons that Locke gives for regarding, e.g. 'red' as a secondary quality equally show that what we term 'primary' qualities are also merely secondary, in that they depend on the capacity of an object to affect a subject. We have in fact no idea of primary qualities apart from secondary: any extension must be some colour, even if only black or grey.

Berkeley's criticism has to be understood against the background of a theory which considers the possibility that there is no such thing as 'matter', that all that exists are perceptions. As another way of putting your 'veil of perception' argument, we could say that Locke is assuming, without warrant, that material substance exists, whereas all we are given are perceptions.

In reply one might argue that there must be SOMETHING that causes these perceptions, in other words something that plays the part of matter and its primary qualities. For Kant, this 'something' is 'noumena' or 'things in themselves', which exist outside of space and time. For Berkeley, it is the infinite mind of God.

In both cases, however, one feels that the point of the primary/ secondary quality distinction has been lost. OK, it turns out from a metaphysical view that 'matter' is not ultimately real. Nevertheless, surely there is a point in distinguishing primary and secondary qualities along the lines the Locke distinguishes them, even if it turns out that the distinction is only relative from the point of view of metaphysics.

You allude to recent developments in physics, such as quantum mechanics. 'Matter' and 'space' are not what we thought they were. However, Locke can reply that so long as we accept that the physical world is ultimately real (contra Berkeley and Kant) then there will be some physical properties, WHATEVER THEY MAY BE, which ultimately account for the fact that we have perceptions of secondary qualities. And these, physics has discovered, are the real 'primary qualities'.

All the best,


Saturday, March 17, 2012

Reasons for Leibniz's theory of monads

To: Yasuko S.
From: Geoffrey Klempner
Subject: Reasons for Leibniz's theory of monads
Date: 2 May 2007 10:30

Dear Yasuko,

Thank you for your email of 30 April, with your essay in response to the University of London question, 'What is a Leibnizian monad? What reasons does Leibniz provide for his claim that such monads exist?'

You have given a clear account of the theory of monads, indicating the main reasons why Leibniz holds this theory.

I have some thoughts about the question itself, and would also like to suggest some additional aspects of the monad question which are worth considering.

As you know, Leibniz published very little. The 'Monadology' presents his views in a simplified form, suitable for amusing the courtiers of Hanover but unsatisfying to the more inquisitive philosopher. Additional arguments are to be found in his scattered letters. For example, the Oxford Companion to Philosophy article on Leibniz quotes from his correspondence with de Volder. There is no way a student can study more than a fraction of Leibniz's voluminous correspondence so you have to rely to some extent on secondary literature to point out the most significant statements.

It is notable that the essay question asks 'What reasons does Leibniz provide...?' rather than the usual formula, 'What arguments does Leibniz give...?' There is no place where Leibniz laid out all his arguments for monads. The wording of the question gives you a bit more license to give 'Leibniz's reasons' even though there may be no particular passage where he explicitly states these reasons. In other words, what you are being asked to do is articulate the monad theory, and explain why Leibniz believed it.

One additional point to make about the question is that Leibniz does not merely claim that 'monads exist', but that nothing exists apart from monads. Monads are the only thing that exist.

Your explanation of the argument about simplicity and complexity is nice and clear. A point that I would make is that it looks at first as though Leibniz is relying on a blatant fallacy: 'There must be simples because there are complexes.' This fallacious because in stating that there are 'complexes' Leibniz is simply assuming what he has set out to prove, that it is not the case that existing things can be divided ad infinitum. In other words, the retort would be, 'There are no "complexes" in your sense.'

In his defence Leibniz would argue that in order to exist, an entity must exhibit 'true unity'. True unity cannot be found in infinitely divisible matter. So this is the real core of the argument. (I am only repeating what you say, but showing the 'logic' of the argument more clearly.')

What other reasons can be found for the monad theory?

The fact that monads provide a solution to the problem of mind-body interaction is important. It is incomprehensible how a Cartesian soul can interact with matter. Leibniz was not the first to consider that the apparent causal interaction between mental and physical can be explained by the theory of 'occasionalism' put forward by Malebranche. However, the monad theory is a significant advance on Malebranche's view because it explains how the states of a monad are a causal consequence of its previous states.

This brings us to the most significant way in which Leibniz departed from Descartes' view of physics. Leibniz criticized Descartes account of material substance on the grounds that it fails to explain the phenomena of force and inpenetrability. Cartesian physics is based on motions of volumes defined in geometric terms. As a result, Descartes was led to the idea that an impulse from a non-material soul can alter the direction of motion of 'animal spirits' without applying any physical force. However, this is impossible in Newtonian physics, which is based on the conservation of energy rather than the conservation of momentum. Leibniz believed that his monad theory was able to account for the aspect of 'force' which is not visible, but necessary in order to account for the phenomena which we observe.

When we observe the motions of material objects, we do not see the forces that are at work. Yet there must be such forces, in order to account for the observed laws of motion. You can't do this, as Descartes tried to do, by means of geometry alone. The actions of monads, each unfolding according to its individual concept, seem to provide the crucial explanation which is missing from Descartes' account of the interactions of material objects. I think that this was a very important consideration for Leibniz.

There are two further reasons which should be mentioned.

Russell, in his book on Leibniz, argued that the monad theory followed from Leibniz's PIS (predicate in subject) principle. Leibniz held this principle, Russell believed, because he wasn't able to grasp the idea of a 'relation' between objects, as something which logically cannot be reduced to predicates of the two objects. However, it is one thing to show that a particular theory can be deduced from a given premise, and quite another thing to claim that this IS the reason why the theory is held. It could equally be argued, in the case of Leibniz, that he held the PIS principle because he had independent reasons for holding the monad theory. So Russell is wrong in his simple characterization of the motivation for Leibniz's theory. Or, at least, the case hasn't been proved.

There is another reason for the monad theory which I think is significant. We can see this if we compare Leibniz's theory of monads with Berkeley's immaterialism. Berkeley's dates are later than Leibniz, but it is arguable that Leibniz's theory is the more sophisticated.

In Berkeley's theory, to exist is to 'perceive or be perceived'. All that exists are God, finite spirits (ourselves) and the perceptions in God's mind which we share. Why didn't Leibniz consider this possibility? On Berkeley's theory, just as on Leibniz's theory, physical objects are merely 'phenomena' or appearances. What is real are souls. The crucial defect in Berkeley's theory, from Leibniz's point of view, would be that phenomena are pure objects of perception which do not correspond to any subject. They are, in effect, merely a show which God puts on for our benefit. Whereas in Leibniz's theory, every observable phenomenon corresponds to an existing entity with its own point of view, as indeed we are ourselves.

As it stands, your essay provides a clear and straightforward answer to the question. The additional points I have mentioned are merely to give you something to think about, which might or might not be useful depending on what questions come up in the exam paper.

All the best,


Thursday, March 15, 2012

The Shoah and the problem of evil

To: Edoardo S.
From: Geoffrey Klempner
Subject: The Shoah and the problem of evil
Date: 30 April 2007 11:26

Dear Edoardo,

Thank you for your email of 25 April, with your essay for the Associate Award, 'God and evil, an unanswerable age-old issue'.

The first thing I must say is that, at 7910 words, this is over three times the target length of essays submitted for the Associate award. When you come to submit your portfolio of four essays, the length would have to be drastically reduced. I would say, three and a half thousand is the absolute maximum for any one essay.

Much of your essay reads like a report of your very extensive reading on this subject. I would have liked to have had a much clearer view of how you see this problem. The main topic is clearly the significance of the Shoah in relation to the traditional problem of evil. Does the Shoah, in fact, result in a fundamentally different way of understanding this problem?

While fully accepting that the Shoah is the worst thing mankind has done to date, the traditional arguments still hold good: to ask God to create a world and to ask him to make it an earthly paradise is to ask for a logical contradiction. Creation is, by definition, independent of the creator. Creation follows the laws that the creator has laid down - whatever they may be. You can't make laws which allow for the possibility of hurricanes without there ever being hurricanes. You can't make laws which allow human beings to evolve, as creatures capable of making decisions, without a human being ever deciding to do wrong.

The Shoah was terrible, but it is not the worst thing that we can imagine. The Nazis' 'final solution' to what they saw as a plague on humanity reduced human beings to things. The sheer horror of the extent of dehumanization required for the extermination machine is unbearable for anyone who contemplates it. (I saw the eight hour documentary, 'Shoah', and that was enough for me.)

And yet, I can think of something worse.

It is the age-old question of whether a man can coherently say, 'Evil by thou my good.' Nazis or Nazi sympathizers might say this on occasion, but their actions generally belie their words. Nazi mothers and fathers did not, as a matter of recorded fact, torture and eat their own children just for the sake of doing evil, or any number of other actions which good taste forbids me to list. Traditional depictions of hell come close but not nearly close enough.

I was once approached by a prospective student who described himself as a 'Priest of the Temple of Set'. I had to look this up on the internet. Apparently, Satanism is still thriving in the 21st century. One seemingly innocuous description of what the Satanists believe is that God is 'only finite'. This gives freedom to human beings to aim to develop ourselves and become greater and greater without limit. However, if we look into this formula further, we find the essential recipe for evil. There is no right or wrong: only what I myself WILL.

Yet is the idea of a finite God so different from the radical theologians' claim that after the Shoah, we realize that God is limited, after all?

My sister, who is a Rabbi is an admirer of Emil Fackenheim. She is one of those who believe that what the Shoah shows is that God is not omnipotent. However, I don't see why a theist has to make this fatal and crippling concession. How much power are you going to take away from God? If God is not all powerful (within the bounds of logic) why can't anyone be God? Why can't Eric Clapton be God? (as the fans of the famous rock guitarist call him).

This idea of a God who 'apologizes' for his impotence is pathetically anthropomorphic; at least, that is what a traditional theist would say. That's the best that can be said. The worst is that to worship a limited God is no different from worshipping Satan.

Another point that can be made is that on the traditional view, a few years on this earth is followed by an eternity in paradise. How can one possibly quantify or compare a limited time of suffering, however intense, with eternal joy? Belief in Hell and eternal damnation is a far more serious challenge to the idea of a benevolent God than any evil found in this world.

On a practical note, if you want to include this topic in your Associate award portfolio, my advice would be to concentrate on one aspect of the problem of evil. There is no way you can cover the entire history of philosophical thought on this topic. For example, as I have indicated above, you could confine the discussion to the impact of the Shoah. Or look at conceptions of God as less than omnipotent. Or you could concentrate on the traditional 'free will' argument which as I have tried to indicate still has a lot going for it.

All the best,


Should we get rid of the concept of personal identity?

To: Gordon F.
From: Geoffrey Klempner
Subject: Should we get rid of the concept of personal identity?
Date: 26 April 2007 10:57

Dear Gordon,

Thank you for your email of 21 April, with your essay for the Philosophy of Mind program in response to the following two questions:

1. 'Can one give adequate criteria for the identity of a person over time? Illustrate your answer with thought experiments describing 'problem cases' of personal identity.'

2. 'What the thought experiments of fission, fusion etc. show is that 'personal identity' is a philosophically incoherent concept, and ought therefore to be dispensed with.' - Discuss.

Richard Parfit is an Oxford philosopher who argues in his book 'Reasons and Persons' against the 'importance' of personal identity. He sees his project as ultimately arguing for a moral point of view where the best action is one that leads to the maximum 'benefit' for all, where the fact that one of the persons is 'me' is not a relevant consideration.

Leaving aside the claim about ethics, there are two main reasons for resisting Parfit's conclusion. The first is that we find the thought experiments sufficiently gripping to be incapable of feeling indifferent to the question whether 'I' will survive or not in a given scenario. The second is that, contra Parfit, there are very important consequences of identity which would require turning our moral and social institutions upside down if we decided to rid ourselves of the notion of 'same person'.

Parfit can reply that our 'intuitions' are merely symptoms of philosophical illusion, and that if our institutions are based on an illusion then we are better without them.

You give a clear and logical appraisal of different candidates for the 'i-factor' which embodies the necessary and sufficient conditions for personal identity over time. You claim 'agnosticism' on the question whether not there is a 'soul' which would provide the ultimate, non-negotiable (but also, alas, unknowable) i-factor.

However, even if one is agnostic about souls, there remains room for debate over whether we can, or should, attempt to defend the notion of personal identity in the face of the various counter-examples.

For example, suppose that someone successfully constructed a person-duplicating machine. This threatens the logic of identity, because of A=B and A=C then B=C, as a matter of logic. The statement not-(B=C) entails not-(A=A) which is a contradiction.

However, as David Lewis has pointed out in one of his articles, we can save the logic of identity by retrospectively deeming that when a person A enters into the duplicating machine, and B and C emerge, there are and always were two persons, A-B and A-C sharing part of their life history. In the same sense, we can talk of two 'branches' of a tree, which share a common part.

I like this solution. It doesn't allow us to 'say what we like'. B and C are insistent that they were both A, and these claims are fully justified. A did not die. Being duplicated is a way of surviving.

Objections have been raised, however, on the grounds that it reduces persons to 'life histories in the making'. But what's so bad about that? If duplication did become part of everyday life, this would be the most logical response, requiring the least violence to our intuitions and social institutions. (Of course, there would be significant stress on those institutions, but there is no solution that avoids stress.)

Memory is the other big obstacle. As you point out, memories fade in time. Parfit relies on this for his 'Methuselah' thought experiment. Imagine beings like us, except that they live for a hundred thousand years. During this time memories fade and are replaced by other memories. When someone tells me something that GK did 1000 years ago, this means absolutely nothing to me, because there is not the faintest recollection. Yet there was no point where psychological continuity ceased.

Someone who thinks that personal identity 'matters' - in other words, someone who disagrees with Parfit's conclusions - needs to have a principled way to answer this challenge. Because it seems to show that the logic of identity simply breaks down and can't be saved when applied to the identity of persons over time.

My response is that I don't accept the assumption that personal identity must be an all-or-nothing matter. Persons have an identity, which is sufficiently robust to cope with all sorts of counterfactual situations, including the science fiction scenarios like body-duplication, or 'beam me up Scotty'. However, we are still dealing with the empirical world, not the world of numbers. There will always be vague and borderline cases, because things in the real world don't always have sharp outlines.

All the best,


Heraclitus: we never step into the same river twice

To: Katherine A.
From: Geoffrey Klempner
Subject: Heraclitus: we never step into the same river twice
Date: 25 April 2007 11:28

Dear Katherine,

Thank you for your email of 19 April, with your second essay for the Ancient Philosophy program, in response to the question, ''Upon those that step into the same rivers different and different waters flow... they scatter and... gather... come together and flow away... approach and depart'. - What did Heraclitus mean by his famous assertion that we never step into the same river twice?'

I don't normally quote from letters I have written to other students, but in this case was taken aback by the coincidence. This morning, I was commenting on an essay by Stuart, one of my students who is taking the BA in Philosophy via the University of London External programme. Stuart is retired, and lives in Canada. The question, set by the UoL examiner, was, 'The ordering, the same for all, no god or man has made, but it was, is and will be: fire ever-living, being kindled in measures and going out in measures.' (Heraclitus fr. 30.) Discuss.'

Here are the crucial bits from my email to Stuart:

'... There is a lot of philosophical meat in the issue over the traditional view of omnipresent flux and the view preferred by a number of recent commentators including Kirk and Raven that all Heraclitus was saying is that all things are in a process of change but 'not all at once' [...]

'According to Kirk and Raven, on Heraclitus' theory some things change rapidly, while other things change very slowly. If we were to look very closely at a rock, for example, we would see that the rock was undergoing a process which, over a few thousand or hundred thousand years would produce a visible change. In other words, in this world, nothing is immutable. But how does that contribute to the on-going debate? Thales or Anaximander or Anaximenes could have said the same [...]

'Heraclitus thought that he was putting forward a radical proposal which few mortals were equipped to grasp. The alternative interpretation just doesn't seem radical enough.'

- As you can see, I totally agree with you that Heraclitus thought that what he had to say was 'radical and extremely important'.

The first point that needs to be discussed is the question of what it means to say that 'X changes', for any entity X. In language, we have nouns and proper names which refer to objects. 'Katherine', 'the tree outside my window', 'Canada', 'the Milky Way' and so on. As a matter of logic, the possibility of names for things implies a distinction between the 'essential' and 'accidental' properties of a thing. The essential properties are such that, if they were to be lost, we would say that the entity in question no longer 'exists'. For example, it is an accidental, and not an essential property of the tree outside my window that the blossom has come out. By contrast, if the tree was cut down and the wood used to make a shed, we would say that the tree no longer exists, even though its wood survives.

The Presocratic philosophers were struggling to understand the logic of change. The question they asked themselves was whether there was anything constant which remains in existence when an object ceases to exist. For example, the tree. But wood can be burned. Then all that is left is smoke and ash. Is there *something*, perhaps something we can't directly see, which remains in existence when the tree is transformed into a shed and the shed is transformed into ash?

Modern science has an answer in the theory of molecules, atoms and subatomic particles. Thales and Anaximenes seem to be putting forward a similar 'physical' theory in claiming that the ultimate 'stuff' is water (this is controversial in the case of Thales, who may have just meant that all things come from water) or, in the case of Anaximenes, air.

By contrast, the view of Heraclitus is that there is no ultimate stuff. He is not saying that things are 'made of' fire in the sense that Anaximenes said that things are made of air. Things change, according to Heraclitus, but there is no ultimate 'stuff', no ultimate 'subject' of change. The only thing that continues is the Logos, the law of change.

That is radical. Other philosophers recognized the 'impermanence of things', but only Heraclitus took this thought to the extreme of denying that there is any underlying substrate behind the changes.

From the point of view of logic this raises very difficult issues. Language cannot even get going unless we identify 'subjects' to which we attribute various 'properties', like the blossoming tree. So Heraclitus is led to question the very nature of language itself. On the view of total flux, the words that we apply, like 'river' or 'rock' are merely conventional labels for patterns of change. The underlying reality of flux cannot be literally described, but can only be conveyed in similes and metaphors.

It is therefore no accident that Heraclitus was driven to speak in 'riddles'. We cannot 'see' or 'describe' a world where there are no objects, only processes. Logic forces us to speak as if there were permanent 'things' or a permanent 'stuff' underlying the changes that we do see. But this logic, Heraclitus ardently believed, is ultimately misleading as a guide to the nature of ultimate reality.

All the best,


Tuesday, March 13, 2012

Essays on Heraclitus, testimony and tomatoes

To: Stuart B.
From: Geoffrey Klempner
Subject: Essays on Heraclitus, testimony and tomatoes
Date: 25 April 2007 10:50

Dear Stuart,

Thank you for your email of 16 April, with your University of London essays in response to the following questions:

''The ordering, the same for all, no god or man has made, but it was, is and will be: fire ever-living, being kindled in measures and going out in measures.' (Heraclitus fr. 30.) Discuss.'

'Much of what we ordinarily call knowledge involves information that we believe only on the basis of what others have told us - i.e., on the basis of testimony. What conditions have to be met for us to gain knowledge from the testimony of others?'

'What is the relation between perceiving the redness of a tomato and knowing that the tomato is red?'


This is a very good essay with which I have few disagreements. The only problem was that despite having a Greek font on my computer the quotations reproduced as lines of question marks.

In an exam, it is OK to use transliteration, e.g. 'cosmos', 'psuche', etc.

You gain marks for showing that you know the context from which the quote was taken, as well as for giving plausible alternative readings and explaining their consequences.

I think that there is probably more scope for philosophical discussion than you have allowed (in other words, you are over-correcting in response to my previous comments).

In particular, there is a lot of philosophical meat in the issue over the traditional view of omnipresent flux and the view preferred by a number of recent commentators including Kirk and Raven that all Heraclitus was saying is that all things are in a process of change but 'not all at once'.

Both alternatives deserve to be explained more fully. I may have mentioned that I prefer the traditional view. There is no 'substance' as Thales, Anaximander and Anaximenes believed.

According to Kirk and Raven, on Heraclitus' theory some things change rapidly, while other things change very slowly. If we were to look very closely at a rock, for example, we would see that the rock was undergoing a process which, over a few thousand or hundred thousand years would produce a visible change. In other words, in this world, nothing is immutable. But how does that contribute to the on-going debate? Thales or Anaximander or Anaximenes could have said the same.

There is a tension here with your describing as 'traditional' the view that the substance of the universe is 'fire'. However, this can be resolved by replacing 'substance' with 'arche'. The point of the Platonic view is that everything is the kind of thing that fire is; only fire demonstrates this in the most spectacular fashion. Nothing has any substance, everything is like fire, or like a river.

Does it follow that there can be no knowledge of anything? Plato has an agenda - to argue that even though the phenomenal world is just as Heraclitus described it, there also exists a world of forms in virtue of which language and communication are possible. However, Heraclitus has an adequate response without recourse to a theory of forms: we 'know' objects by conventional names, like 'river', and these are the currency of normal discourse. What we don't know - or only dimly grasp as a result of wrestling with Heraclitus' theory - is the ultimate constitution of things which can only be approached by means of similes and metaphors.

Heraclitus thought that he was putting forward a radical proposal which few mortals were equipped to grasp. The alternative interpretation just doesn't seem radical enough.


I couldn't find any specific things to disagree with here. The main problem is that although you mention or allude to different views such as coherentism, contextualism, reliabilism, tracking truth most of what you say just seems like a recapitulation of common sense. In other words, it is hard to identify targets for critique.

When I was at Oxford, Gareth Evans - then a rising star in the philosophical world, before his untimely death - was talking about the problem of testimony as one of the most exciting and challenging problems in semantics and epistemology. Can you think why?

There are various moves one can try to make. How are things different if we imagine a visitor to another planet who has to decide, from scratch, whether to believe what he is told by his alien hosts? What does the answer to that question show about the importance of the role of a shared language and nature?

Or imagine a young child abandoned on a desert island with a library of books. The child grows up, teaches himself and learns about the world. What is he missing? Does he 'know' less?

What is the significance of the fact that I am not the end point in the chain of information transmission but am myself called upon to testify for someone else's benefit? If the knowledge is for me, I can make an assessment depending on the risk, as you say. But if I am to testify to someone else, what standards should I employ, not knowing what use that person wants to put the knowledge so gained?

Is the credibility of knowledge claimed weakened as the chain lengthens? If not, why not? We do normally raise questions, e.g. when reading a newspaper article, as to whether what we are reading is first-hand or second-hand information.


I am still not convinced that the sense datum theory and phenomenalism are relevant to this question, at least not to the core of what the question is about. Of course, you can ask what the sense datum theorist or phenomenalist would say, and get some mileage but there remains a core issue even when these alternatives are rejected.

The fact that we don't (or, rather can't) attend to all the features of our visual field at any one time can be explained in terms of Dennett's distinction between levels of conscious 'awareness'. For example, driving along in a car while thinking about this essay question, you might stop at several red lights and then go promptly on green without every consciously applying the concepts 'red' or 'green' to your experience.

No-one observing your behaviour would doubt that you perceived the greenness of the traffic light. However, equally, one would say that you knew that the traffic light was green. If you didn't know that it was green then that would be a case of reckless driving. For example, if the sun is coming from the wrong angle you might need to crane your neck or squint your eyes before satisfying yourself that the light has changed to green. In favourable conditions, by contrast, you just know that the light has changed without thinking about it.

All the best,