Wednesday, 1 February 2023

Why is there something rather than nothing?


This was the question at our Cambridge philosophy café on 22 January 2023. The first impression is that it is both a question that demands a decent answer, and a question that cannot have one. This post does not provide an answer. Instead, it sketches some of the territory.

Why is an answer demanded?

There are items of many types in the world (meaning not just the world as it is today, but the world with all its history). There are physical objects, events, relationships of space and time (or of spacetime when we focus on physics), laws of nature, mathematical results,  thoughts, feelings, and so on. We may be more or less generous in what we regard as an item in the world. But whenever we admit something as an item, we can ask why it is in the world. And we tend to think either that an answer will already be known, or that the discovery of an answer would be perfectly conceivable. Even if we do not have much hope that an answer will in fact emerge, for example where historical records have been lost, we still think that an answer could have been found if things had been different in perfectly identifiable ways. At the extreme, we might forgo even that hope and say that no answer could be found, but even then, we would think that there was some unknowable reason for the presence of the item in the world. 

To put all this in traditional philosophical terms, we have a strong inclination to subscribe to the principle of sufficient reason. And we are disturbed when quantum mechanics suggests that there may be no reason why some observations rather than others come to be made. We are left hoping that physics will advance to restore compliance with the principle. The hope may be forlorn, but it is there.

If we routinely find reasons for the presence of items in the world, and if we can put quantum mechanical worries to one side by noting that they do not extend to everyday items when characterized in the macroscopic terms we in fact use to individuate and describe those items, it would seem reasonable to ask why the whole ensemble is present (not present in the world, for the ensemble is the world, but simply present). And the question of why is there something rather than nothing is a less demanding question than that of why the particular ensemble we find is present, in that an answer to the latter question would automatically be an answer to the former one but not vice versa. Moreover, not only would the question seem reasonable. A response that it should not be asked, or could not be answered, would seem to be unreasonable.

Types of explanans

Our explanandum is the existence of some non-empty world or other (we do not need to explain its actual make-up). Our explanans could be causal and within the world, causal and external to the world, or non-causal.

By way of background, we shall make some remarks on ways to explain the existence of items within the world. Then we shall consider causal options, followed by non-causal options. Finally, we shall look at the option of dismissing the question.

Ways to explain the existence of items within the world

We can find reasons why individual items are in the world.

Sometimes reasons are directly causal, as when stresses between continental plates cause earthquakes, or the values of certain physical constants together with some conditions in the early universe determine which forms of matter have come into being.

Sometimes reasons are indirectly causal. We may for example say that a particular taxonomy of animals has been created because of the causal influences that have produced the actual variety of animals. Or we may say that a thought exists because of causal influences on neurons. Or we may say that an emotion in general (as distinct from individual instances) exists because causal patterns in the world are such as to generate particular types of human reaction in particular circumstances, where those reactions are reasonably systematic.

Sometimes reasons are not causal at all, as when we identify the reason why some mathematical statement is a theorem. 

There are also items that would be amenable both to non-causal explanation and to indirectly causal explanation. For example, the existence of Mannerism as an item in the history of European art could be explained non-causally by the presence of distinctive formal features in the relevant paintings and sculptures. And it could also be explained causally, albeit in an indirect way, by an analysis of the thoughts in the minds of artists and their patrons, in turn explained by a causal history of their neurons and of preceding developments which created the artistic context.

Internal causes of the whole

Now let us consider the whole universe, in all its history. The prospects for a causal explanation that relies on causes within the world are not bright.

Causes generally precede their effects. A cause might arise at the same time as its effect, but even then we require a direction of causation. If one thing caused another, it was in fact the case that the second thing did not cause the first one, even if in other circumstances the second thing could have caused the first one.

Moreover, we do not expect A to cause B to cause C to cause A. In mathematical terms, we want the causal connections between things to form a directed acyclic graph. In particular, cycles directly from something to itself are ruled out. No self-caused things are permitted.  We can however allow that A might cause B on some small scale, which then caused A to grow, which caused B to grow, and so on. Causal feedback is allowed.

(As usual, quantum mechanics complicates things. See for example the analysis and the references to earlier work in Barrett, Lorenz and Oreshkov, "Cyclic Quantum Causal Models", at

As soon as we have a direction of causation, we get causal chains to trace backward. We would expect to find something at the head of a chain into which all chains merged as we worked backward, or maybe several things at the heads of various chains which did not merge. A head item would explain everything that followed in its chain, so if it went unexplained, we would still not have explained why there was something rather than nothing because explanations for the existence of other things would be contingent on its existence. And everything that was not at the head of a chain would have to stand in some chain or other, so its existence would only have such a contingent explanation.

At this point we may remark that telling us that empty space has non-zero energy does not answer the question, at least not in the obsessive form in which philosophers are apt to pose it. Empty space with its scientifically determinable properties is not nothing, but a something that could have led in a causal way to what we see today. It has been said that when Lawrence Krauss published A Universe from Nothing, it should have been entitled A Universe from Not Very Much. And to a philosopher, that criticism has bite. (Krauss is however fully aware of the issue. He discusses it in chapter 9. On page 149, he acknowledges that he takes empty space and the laws of physics to exist within his "nothing".)

We must tread carefully here. It would be possible for everything to be caused without there being anything uncaused, in the way that every positive real number has a predecessor positive real number (in fact, infinitely many of them) without there being any first one.

More interestingly, we may need to be careful because temporal precedence relies on there being time, and strange things may have happened with spacetime at the very beginning. Temporal precedence may not be the only type of precedence to give a direction of causation, if we allow for causes to be simultaneous with their effects. But it is the prevalent type. If the notion of temporal precedence were to get into difficulties in the context of the early universe, cosmologists of that early stage might be able to offer us a loophole that would allow a cause of things which was within the universe to be fully explanatory.

There would also be an argument to be had over whether one should see the quest for a causal reason for there being things in general in the same terms as the quest for a causal reason for there being some particular thing or other, even an unspecified thing that would stand as a representative member of things in general.

While one might raise such doubts about the easy argument that there cannot be, within the universe, a cause of the collectivity of things, there is enough room for worry that we should not expect to find such a cause.

External causes of the whole

Perhaps there could be a causal explanation which would be saved by not being within the world, so that it did not itself stand in need of a worldly causal explanation.

Sadly, this idea looks like a non-starter. Something that was causally effective but outside the world would look suspiciously like a god. And what could reasonably be substantiated about a supposed god would be so little as to make the supposition of one nothing more than a place-holder for an answer. Theists may rely on holy texts to describe their gods, but those texts are claims, not evidence. And in the absence of substantiated properties of a god or gods, the assertion of their existence does no more to answer our question as to why there is something rather than nothing than to say "If we had an answer, it would go here". Leibniz, who made an explicit connection with the principle of sufficient reason, may have thought he had done more (Principles of Nature and of Grace, 7-9; Monadology, 36-39). But he had not.

Non-causal options

It is time to look at explanations which would avoid the requirement to respect a unidirectional relation from each specific explanans to its specific explanandum. They would be non-causal explanations.

Such explanations would comprise facts about the world, or facts about the abstract realm independently of any connection it might have to the world, rather than comprising things within or outside the world. The facts might mention things, but they would not be those things. Given the difficulty of conceiving of facts about things outside the world, aside from unsubstantiated and possibly incoherent claims about supposed gods, we need not distinguish between internal and external facts in the way that we distinguished between internal and external causes. But we must recognize that facts may be about abstract entities, any relationship or lack of relationship of which to the world is not given and is not to be presumed (beyond the observation that logic and mathematics are readily applicable to the world). Such abstract facts may include structures of relationships in which the specific relata are unimportant.

We seek facts that would make the existence of something rather than nothing unsurprising. There are options.

Many possible universes

One option is the claim that there are a great many possible universes. An easy argument would be that since there would be only one possible empty universe and a vast number of possible non-empty universes, it is no surprise that a non-empty universe should turn up. All that would then be lacking would be an explanation of why any possible universe at all was actual. If some random one were actual, it would probably be a non-empty one.

This argument would rely on the claim that there was only one empty possible universe (or at least, not many of them). Fortunately, within the realm of the merely possible, the claim of a single empty universe could be made just as, in mathematics, there is only one empty set. It is only in the concrete world that there are many empty boxes.

Many actual universes

Another option is the multiverse claim that there are in fact a great many universes, all but one of them beyond our ken. It would not be necessary to argue that most of them would be non-empty. Any one non-empty universe would suffice. But this argument would only give a route from there being many universes to there being something rather than nothing. It would leave unanswered the question of why there actually were many universes.

Either this option or the option of many possible universes could be backed up by a weak anthropic principle to the effect that whatever we observe will be a universe sufficiently complex to support conscious life, and therefore not empty. An empty universe might be a possibility, or there might be one or more empty universes among a number of actual universes, but we could not be in an empty universe.

The universe as an abstract structure

A third option would be to say that the universe was itself some abstract structure, not dependent on anything for its existence.

The leading example is the mathematical universe hypothesis that Max Tegmark has set out in Our Mathematical Universe (2014), but that is better and more briefly explained in his paper "The Mathematical Universe" from 2007, available at (take care to obtain version 2, dated 8 October 2007).

In Tegmark's view, the universe actually is a mathematical structure. This claim goes beyond the observation that the universe is amenable to mathematical characterization. Moreover, we are substructures within that structure who are conscious and self-conscious by virtue of the complexity of those substructures.

Tegmark's approach has the advantage that it is plausible, although not uncontentious, to think that mathematical structures simply exist, independently of anything else's existence. In particular, and importantly for him, they can be seen as existing independently of any human predisposition to think in particular ways (for example to think in terms of objects and causation). They are all form, definable in strictly mathematical terms, and no non-formal content. And this is argued to be enough to characterize any universe. As physics digs deeper and deeper into the nature of reality, it identifies symmetries and conservation laws which say everything that physicists feel the need to say. The need for a separate stage of explaining how the mathematical structures identified give rise to what we perceive does not detract from the sufficiency of physics without that extra stage.

Tegmark's approach can however be challenged.

An apparent difficulty is that we need to explain how it is that the particular mathematical structures we find here are instantiated, rather than all possible structures being instantiated to form each and every possible universe. (He does posit a multiverse.) The problem is that once mathematics gets going, even with an empty set and minimal set theory, there is nothing within itself to stop its expansion. We would get all of mathematics everywhere, subject to a few large-scale decision points such as whether to adopt classical or constructivist mathematics or whether to adopt the axiom of choice.

This apparent difficulty is easily addressed. Tegmark thinks that what comprises any given universe is not a theory but a model of a theory. That allows for variation between universes, especially if we allow universes to comprise models of parts of theories.

This does not however leave an entirely satisfactory picture. A clue to the difficulty lies in Tegmark's invocation of the mathematical principle that "same up to isomorphism" amounts to "same" (the 2007 paper, section II.D). If our universe is isomorphic to a mathematical structure, then in his view it is that structure.

The problem is that "same up to isomorphism" does not amount to "same" in the everyday sense of "same". When we think in physical terms, we are happy with the idea of several distinct but isomorphic things. We could even imagine several isomorphic universes within a multiverse, so long as the multiverse was realised in a physical or quasi-physical way and not in a purely mathematical way. We would have to presuppose Tegmark's conclusion that we should think of the universe as a mathematical object in order to require ourselves to think of sameness in the mathematical way. 

Dismissing the question

The option of dismissing the question of why there is something rather than nothing remains.

One could simply take the existence of something rather than nothing as a brute fact.

One could add that the principle of sufficient reason did not have to be accepted. There are after all things in the quantum world which, so far as we can tell, simply happen. More precisely, there are observations which are such that we cannot currently give any sufficient reason why a specific observation was made rather than an alternative.

One could dismiss all questions as to why things were as they were and and simply ask how things came to be as they were. An argument for doing so, given by Lawrence Krauss, is that why-questions assume that there is some purpose to be found, and that there is no sign of any such purpose at the level of the universe (A Universe from Nothing, page 143). But it is not clear that this is so. A why-question need not assume purpose. It may be a rephrased how-question which, in the context of asking why there is something rather than nothing, carries the implication that one is going to go on asking how-questions until one reaches something that plainly has to be the case so that the stream of how-questions can come to a stop.

One could challenge the formulation of the question, on the ground that it was not possible to talk about nothing. But that argument might easily not succeed. While there might be nothing to which to refer, one could talk about the falsity of every proposition of first-order predicate logic which started with an existential quantifier, the variable of which actually bound an occurrence later in the proposition. (This is only a sketch of a solution. It would need to be worked out in detail.) Or one could point out that we have no difficulty in thinking mathematically of the contents of the empty set, even if philosophers have found that natural languages run into difficulties over such notions.

Finally, one could treat the existence of something rather than nothing as a mystery. In the words of Wittgenstein (Tractatus 6.44), "Nicht wie die Welt ist, ist das Mystische, sondern daß sie ist". But that would seem to amount to no more than accepting the existence of something rather than nothing as a brute fact and taking up a particular emotional attitude to the fact, unless one had good grounds to think that the mystical was itself a repository of information that was so far inaccessible and might eternally remain so. That would be a hope without justification.

Wednesday, 8 February 2017

The humerus side of life

In November, when with a friend on our way back from seeing someone depart for Paradise by way of Kensal Green, I tripped and fell on a railway platform and sustained a fracture to my left arm, at the upper end of the humerus. This must rank very low on the scale of injuries requiring hospital treatment, and indeed the orthopaedic surgeon who first looked at it chose to put the arm in a sling and let it heal, rather than resorting to surgery. But the injury was still enough to provoke a few thoughts, which I record here.

Before doing so, however, I would like to record my very great thanks to everyone who helped, both friends and transport and medical staff. Among the latter I number (in order of encounter):

1. the platform staff at Oxford Circus station. They were with me within 30 seconds of my falling, and made sure I was alright and able to continue safely (in the company of the friend who was with me) to where I could get medical help;

2. the pharmacist at Boots on Kingsway whom I first approached in search of a sling and painkillers, who told me that there might be a fracture and sent me to hospital;

3. the Accident and Emergency and Urgent Treatment Centre staff at University College Hospital. I was passed smoothly round the necessary doctors, orthopaedic surgeon, nurses and radiographers, and while work in such departments must be stressful, they were at all times calm and friendly;

4. the staff of the Fracture Clinic at the same hospital, which I visited three times from December up to early February. Again, orthopaedic surgeons, nurses, radiographers and administrative staff ran the operation very smoothly;

5. the radiographer and the orthopaedic surgeon who took a look to make sure there was no displacement when I was in Hong Kong for a while in December;

6. the physiotherapist whose clinic at University College Hospital I now attend, and probably will attend for a little while to come. Each time I go I get a friendly and efficient review of progress, and am sent away with clear instructions as to which exercises to practise.

The National Health Service sometimes gets a bad press. This has been by far my most significant encounter with the Service to date, and I want to say out loud that they have been absolutely superb. The next time you read a story saying that they have got something wrong, please bear in mind that they get things right thousands of times a day, and the newspapers hardly ever notice.

Now to the thoughts provoked by the fracture. None of them is original, but some of them only come to mind in abnormal circumstances.

1. What happens is so contingent on trivial details. If I had stepped off the train a little bit differently, my course might have been to one side of where it was, or my feet might have fallen at each pace a few centimetres behind where they in fact fell, and the trip might have been avoided. As a corollary to this, there was no practical way to see the risk coming. Even approximations to the predictive power of Laplace's demon are unavailable.

2. Following on from this first thought, trivial differences can make a big difference to the next few months. My reading and writing were interrupted and then slowed down, and a couple of talks I was due to give had to be cancelled. (A trip to Hong Kong and Singapore, on the other hand, starting ten days after the accident, went ahead, although I don't think the orthopaedic surgeon in the London fracture clinic was very happy about that.) But the effects need not be life-changing. My life is now back to what it probably would have been if the fracture had not occurred. Of course something life-changing might have happened at the talks, had I given them, but that is mere speculation, and the possibility is too ill-specified for there to be any fact of the matter about whether something life-changing would have happened. (For comparison, I buy a lucky dip lottery ticket for each Saturday's draw, but given that the numbers are generated randomly and depend on the shop one uses and the precise time of purchase, there is no fact of the matter as to whether, when I happen to miss a Saturday, I would have won had I bought a ticket.)

3. It is sometimes said that one should get on and do the important things in life, because one might for all one knows die quite soon. This argument is less persuasive than it used to be, at least when addressed to people who are young or in middle age, because while there are early deaths, the probability of dying when young or in middle age is much lower than it used to be. We should perhaps replace the argument with one which turns on the fact that one might lose some important abilities relatively early in life. My fracture is healing nicely, but I could easily have suffered a permanent injury. And in a world that is structured around people with four fully functioning limbs, good eyesight, and so on, moderate injuries can impose significant limitations, despite provision being made for the disabled. To take a trivial example, when one arm is out of action or cannot be used to apply any significant force, it takes much longer than normal to get dressed, and you have to find someone else to do up your shoelaces.

4. It is remarkable how little one notices about one's body until something goes wrong. The big lesson for me was that no body part is an island. Everything is connected under the skin. Thus for the first week, any movement of the upper left arm was painful. So I took care to do everything with the right arm. But certain movements of the right arm led to pain in the left arm. And if I had to pick something up from the floor, crouching down (moving only the legs, not the arms) also led to pain in the left arm.

Wednesday, 16 November 2016

Court decisions and arguments for them

Here is a little puzzle, inspired by a brief visit to the UK Supreme Court yesterday.

Suppose that an appeal, which turns purely on questions of law rather than on questions of fact, comes to a supreme court. (That is important - we are to assume that this hearing is the end of the line, so if something goes wrong, there is no further appeal procedure to put it right.) And suppose that 9 justices hear the appeal, and decide who wins by a simple majority.

5 justices would allow the appeal, and 4 would dismiss it, so the appeal succeeds. But the 5 are split 3-2. 3 of them reach their conclusion by using argument-3, and make clear their view that another argument, argument-2, would be not merely inadequate but mistaken. The other 2 rely on argument-2, and make clear their view that argument-3 would be mistaken.

The 4 who would dismiss the appeal all rely on exactly the same argument, argument-4.

Given that we expect legal decisions to be made for good reasons, should we worry that the court's decision is opposite to the decision which would be supported by the argument that attracts more support than any other argument?

Monday, 26 September 2016

Tax and software

Here is the response I have just sent to the HM Revenue & Customs consultation paper "Making Tax Digital: Bringing business tax into the digital age", which is available here:

I write in response to the consultation paper Making Tax Digital: Bringing business tax into the digital age, published 15 August 2016. I write as a private individual, not on behalf of any business or organization. (I used to be in charge of tax policy for the Institute of Directors, but I left that post in 2013.)

I only have comments on one topic, the supply of software to taxpayers to enable them to work within the proposed digital system.

The proposal is to make people use software from suppliers who have obtained the approval of HMRC, coupled with the proposal to require software suppliers to agree to provide cut-down versions (which will lack full functionality) for free.

I think this proposal addresses the problem in the wrong way, and in a way that will cause considerable trouble for HMRC. My reasons for saying this are as follows.

1. In order to comply with their legal obligations, many businesses will have to spend money in addition to paying their tax. This is fundamentally wrong. You should be able to have all necessary dealings with the state at no additional cost. (Compare the fact that if you want to go to court without spending money on a lawyer, you can do so by representing yourself.)

2. The software companies will want to offer as little as possible in the free versions, while HMRC will want a reasonable amount to be offered. HMRC will get involved in tangled and wholly unnecessary negotiations, and there will inevitably be the suspicion of cosy deals being done - unjustified suspicion, perhaps, but there nonetheless. HMRC will also be at risk of litigation from rival software providers, when they are seen as having done deals with some providers that are more generous to the providers than the deals they have done with others.

3. The negotiations with providers will go on year after year, over which updates will be provided free of charge.

It would be far better if HMRC did not get into the business of doing deals, but instead did at least one, and perhaps both, of the following. (Of the two, I think the second one, provide a full package, would be the better one.)

A. Publish the interface and allow anyone to produce software

Publish the interface - the exact requirements for any file submitted to HMRC. Then anyone could produce software to match, and anyone could make it open-source if they wanted.

It is not clear how far HMRC already intend to go down this route. Paragraph
2.14 speaks of "developing and releasing new APIs". For this to be satisfactory, it must mean release in full to the public at large (and not just authorized suppliers), and in a form that allows anyone to try out software with them. On this last point, see the remarks by Toby Parkins in response to Q250 of the evidence that the Treasury Committee took on 06 September 2016, available here:

HMRC might object that they need to authorize the software for reasons of security of the HMRC system - they don't want people finding ways to feed false data into the system. While that is a legitimate concern, I very much doubt that the authorization of software would be the remedy. After all, people will find ways to spoof authorized software, and whatever security systems will be used with the authorized software (eg public and private keys) could be made a requirement of the software that anyone was allowed to develop.

Paragraph 2.18 also indicates that HMRC would undertake lots of testing of software, something which would require HMRC only to have to test a few packages. While that might be reassuring to taxpayers, it is unlikely to be necessary. If a product is a duff one, word will quickly spread. And it would be open to HMRC and others to provide sets of test data which people could put into software, and copies of the files which should come out at the other end for sending to HMRC. Consumer groups could then run the test data and compare the files which emerged with the files which should emerge, to see whether the software was any good.

B. Provide a full package free of charge

HMRC could provide their own full-featured package to do everything, including the keeping of accounting records that would feed into submissions to HMRC, free of charge (and preferably open-source so people could make their own modified versions it if they wished, or at least look at it in detail and propose amendments), and fully functional on all of Windows, Mac and Linux.

That approach would be far more likely to wean people off the shoebox-full-of-invoices system of record-keeping than asking taxpayers to spend money on commercial systems. And it would probably involve a good deal less effort for HMRC in total than entering into negotiations with commercial suppliers and testing all their various products.

HMRC's traditional argument against providing full-featured packages free of charge is that it would undermine the private sector software industry. Well, tough. It is not HMRC's job to create work that people then have to pay to get done. The concern in paragraph 2.22 that HMRC should provide reassurance to companies that they could provide both free and paid-for packages and still make money is wholly misplaced. Companies' profitability is not in principle HMRC's problem, and it is only made HMRC's problem if they first takes the decision to rely on commercial suppliers, rather than providing a full and free package.

Moreover, acting to keep commercial providers in business right against the idea of reducing regulatory burdens. And in the old, paper records, days, the Inland Revenue happily provided all the forms you needed, free of charge.

Finally, here is an admittedly off-the-wall suggestion. If HMRC do go down this route, it will be worth considering ways to get a package developed cheaply. It would make a fine project for computer science students - some to write the package, and others to find out what was wrong with it and propose corrections. Just look at what the open-source community has achieved, using collaboration tools like GitHub, and you will see that it really would not be that difficult. HMRC's main concern would probably be time discipline - the package would have to be ready by a certain date in order to fit in with broader plans. But it is not clear that such worries would be any greater than they would be with more traditional methods of software development that have been tried by Government agencies in the past.

Monday, 25 July 2016

Pokémon Go: Philosophy Examination

Philosophy Examination

Subject: Pokémon Go

Answer as many questions as take your fancy

Time allowed: for as long as you have nothing better to do

Note: this examination is based on a simplified version of Pokémon Go, which is not identical to the actual game. The broad idea of capturing different monsters which appear on the screen of a mobile phone when one is in the right area is carried over from the actual game. Other features which are to be assumed are indicated by the questions. Candidates may assume such other features as are reasonable given what the questions ask, so long as no assumptions which would make the questions trivial to answer are made.

1. Assume that when several people are at the same location, surrounding a table, they can all see a monster in the middle of that table, and they see it in ways that reflect their relative positions. (For example, if someone facing south sees the monster face-on, someone facing west sees its right hand side.) And when a viewer moves round the table, his or her view of the monster changes accordingly.

(a) Under what additional conditions, if any, would this be evidence that the monster was real?

(b) What kind of evidence, if any, would help to settle the question of whether the viewers saw one monster or numerically distinct but qualitatively identical monsters?

(c) How would your answer to (b) be affected by whether the monster disappeared from all screens when it was captured by one of the viewers?

2. Assume that a monster is at an absolutely fixed position relative to the Earth's surface. Does it exist when no-one is looking at it?

3. What conditions, if any, of numerical identity over time could be applied to monsters?

4. New monsters are supposed to come out of eggs which have been fertilized and laid following an encounter between two monsters, and the species of a new monster is systematically related to the mother's ancestry. (It seems that these facts are known from other Pokémon games, rather than from Go.) But it appears that no-one has seen a monster lay an egg, and the eggs are simply found.

(a) Is inference to the breeding-and-laying account an example of inference to the best explanation?

(b) Is it a respectable inference (of whatever type it may be)?

5. Monsters are apparently distributed in a way that is positively correlated with human population density. Such a distribution would give people in rural areas very limited access to monsters, unless they travelled to urban areas.

(a) Assuming that there is a cost to the creation and maintenance of monsters, which is a cost per monster unrelated to the location of the monster or the number of other monsters near it, would such a distribution policy accord with utilitarian principles?

(b) If you were behind Rawls's veil of ignorance, would you approve of such a distribution policy?

6. Some of these questions come out of a conversation between the examiner and a (human) interlocutor who is happy to remain anonymous. Other people may have already had and published the same or similar thoughts.

(a) If thoughts which are qualitatively identical to those set out in the questions here have already been captured by others, do they count as captured by the examiner and the interlocutor, and do they get points for capturing them?

(b) Is there any identity other than qualitative identity for (i) thoughts (ii) Pokémon monsters?

Tuesday, 28 April 2015

Buridan's ass

Buridan's ass thought he had the answer. Each time he could not decide between two bales of hay, he would toss a coin. If it came up heads, he would start with the bale on the right; if tails, he would start with the bale on the left.

But there would be an equally good rule, heads-left, tails-right. How could he decide between these two rules?

Then he had another idea. He would build an electronic device with a loudspeaker and a button. When he pushed the button, it would randomly say "Right" or "Left", and he would follow its instruction. It would not matter whether it was genuinely random, or determined but as near random as made no difference (for example, if it picked up whatever radio waves happened to be around and used them to decide when to stop a counter that was flipping left-right a million times a second). He did not have to worry about every philosophical problem.

But the device would not have any notion of the meanings of the words "right" and "left". It would be like the person handling the dictionaries inside Searle's Chinese room. So the ass would have to make an arbitrary choice between the rule that said the sound of the word "right" meant he was to choose the bale on the right, and the equally good rule that it meant he was to choose the bale on the left.

He began to wonder whether there was any way to get rid of the arbitrariness, as opposed to just moving it to a different place. Perhaps there could not be. Perhaps for any rule or system of rules, there would have to be a mirror image rule or system that would always have the opposite effect. This might be an inevitable result of the symmetry of the situation that created the problem.

At this point he felt hungry. He went out into the yard, and was very pleased to see that there was only one bale of hay. And as it was directly in front of him, he would start by eating the middle part of it.

Sunday, 1 March 2015


Oxford University Press have kindly sent me a review copy of Tetralogue: I'm Right, You're Wrong, by Timothy Williamson. It is an introduction to a wide range of philosophical problems, presented as a conversation between four people on a train.

Dialogues have a distinguished history in philosophy: think of Plato, Berkeley and Hume. Many such dialogues steer the reader gently but firmly towards the author's preferred solutions. This one is different. The problems are put in front of us. Some sketches of solutions are identified, and are explored sufficiently to show us that they could not easily be worked up into fully developed solutions with which all would be comfortable. But we are neither told nor shown that one sketch is the right one upon which to concentrate. The reader who asks "What sort of thing does Timothy Williamson want me to think about this?" will get no answer, whether "this" be relativism, vague language, the primacy of science, the status of logic or the nature of ethical claims. Readers can reach their own conclusions, but they need to work at reaching them for themselves. They also need to be wary of identifying with any one of the four participants and then casually agreeing with the chosen one. The participants have such different outlooks that it would be easy to take to one and against the others. Bob insists on making room for the unscientific, Sarah has no truck with such nonsense, Zac is a relativist who always knows that he can be helpful, and Roxana is the Queen of Logic.

For whom is the book? The beginner in philosophy will engage with serious philosophical questions without realizing it. Those who are steeped in the western philosophical tradition will enjoy the many allusions to writers, problems and solutions that are hidden in the dialogue. The benefits to these contrasting readers draw our attention to a third reader, who will get more out of the book than either of the first two. This is the beginner who has the benefit of guidance from an expert who can show where there is more to the dialogue than meets the eye, and who can push the beginner to use the dialogue as a springboard for his or her own arguments. This would be a very good book to use in an informal course for adult or teenage beginners, a course that was aimed at broadening the mind while having fun rather than at passing an examination.

The allusions pose a puzzle. Some of them must be deliberate. For example, on pages 35-36 Zac adopts the voice of Plato's Socrates to commit Sarah to a position with which she is not at all comfortable. Others may or may not have been planted by the author. On page 134, we have a suggestion that we should take into account only the views of those who can look at things from all relevant points of view (those who are both accountants and soccer fans in this case). Is this a deliberate allusion to Mill's justification for preferring the opinion of Socrates to that of the fool, and the opinion of the human being to that of the pig (Utilitarianism, chapter 2)? Or is that connection created solely by the reader? And if the author did not intend the allusion, does it still qualify as an allusion? We might go on to distinguish the case where it was unintended but the words were a consequence of the author's having read Mill from the case where there was no causal connection between that reading and what the author wrote, and then argue about whether the concept of causal connection was the right concept of connection in this context, and so on. Thinking about the author and the reader, rather than solely about the contents of the book, can set off such a torrent of questions. At least we can be confident that the author will be perfectly happy to have given us a meta-problem to ponder, whether he did so accidentally or deliberately.

The last section of the book is about ethics, and the tone changes. The gap between the dialogue in the book and how a discussion might go in a philosophy class shrinks. This is a reminder that ethical issues arise in all of our lives, so that a direct presentation of the issues can engage anyone. It is not only philosophers who see that the issues are important. But this change of tone is no let-down. Like the train blending smoothly into the dusk at the end of the book, the book blends philosophy smoothly into the life of the reader. This is a serious book that is also a lot of fun.

Tetralogue: I'm Right, You're Wrong, by Timothy Williamson. Oxford University Press, 2015, 160 pages, hardback £10.99. ISBN 978-0-19-872888-7.

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