Opposition to consensus

One of the complaints against those who deny, or doubt, anthropogenic global warming, is that they are mistaken. That must be the fundamental complaint. We won't do the right things, unless we get the facts right.

Another complaint, less fundamental but more interesting ethically, is that by opposing the scientific consensus, they get in the way of action. This complaint is sometimes mentioned, for example in paragraph 7 in this piece by James Garvey:

http://www.guardian.co.uk/environment/2012/feb/27/peter-gleick-heartland-institute-lie

There will always be some politicians who will oppose action on global warming, and if some people offer arguments that action would be wasteful and pointless, they will give those politicians material to use in their own campaigns. This will reduce the probability of action at the level of governments, whether they would work singly, or in co-operation at the international level.

My question here is, is there a specific ethical failing of opposing a consensus, where the result is likely to be to delay action, or to reduce the scale of action, to solve a problem that is real and pressing if the opponents of consensus are indeed mistaken?

If the opponents know that the evidence for their position is of poor quality, or if they are reckless as to whether it is of good or poor quality, there is a failing, but it is of a rather more general sort than any failing of opposing a consensus. The failing is that of not being sufficiently careful to put forward true claims, and to avoid making false claims, in a situation in which one ought to take more than usual care, because the consequences of people being misled are so serious. William Kingdon Clifford set a high standard here, in his essay "The Ethics of Belief". His standard is conveniently summed up in his words towards the end of its first section: "It is wrong always, everywhere, and for anyone, to believe anything upon insufficient evidence". We might debate whether this was an appropriate standard when the stakes were very low. But with global warming, the stakes are very high, and the standard is undoubtedly apt.

Not all global warming sceptics are reckless as to the quality of the evidence for their position. Some would be too ill-informed to be aware that the quality of their evidence needed to be reviewed. But the corporate lobbyists, and their think tank pals, who push the sceptical position, cannot plead that kind of innocence. They know about the evidence. They study it when formulating their positions. They also know about the need to look critically at the quality of evidence. They spend a lot of time criticizing the evidence on the consensus side. Given that the overwhelming majority of scientific, as distinct from political, commentary, is on the side that anthropogenic global warming is real, it must be reckless for them to take a contrary position, unless they have a large and thoroughly-analysed body of evidence to support that contrary position. The corporate lobbyists and think tanks that take up global warming scepticism have no reason to suppose that they have such a body of evidence. They are, therefore, at best reckless, and they stand condemned by Clifford's standard.

This does not mean that there is anything wrong with their challenging the detail of the scientific claims that are made, searching for errors, and highlighting alternative interpretations of the data. It does, however, mean that they should not crow that there is no sound support for the consensus scientific view, when they have no good reason to think that they have established that the consensus scientific view is baseless. One can be reckless, not only in taking up an overall position, but in making claims about how much one has shown, or about the extent to which the things one has shown undermine the other side's view.

Now let us leave the example of global warming, and ask whether there is a specific ethical failing of opposing a consensus, assuming that:

(1) the opponent of the consensus is not reckless as to the quality of the evidence for his position;

(2) if the consensus is correct, failure to act as the consensus view would recommend would have serious consequences;

(3) if the consensus is mistaken, there would be significant waste in acting as the consensus view would recommend.

It seems to me that there is no ethical failing here, unless, perhaps, the opponent of the consensus is in a position of exceptional power, so that his position is very likely to prevail, whatever the merits of the arguments on his side and on the consensus side. Absent such power, the opponent is acting in a way that is, in general, likely to lead to the advancement of our knowledge. The opponent is simply engaged in subjecting other people's claims to criticism. Criticism exposes error, and can strengthen correct positions that show themselves able to withstand the criticism, as Mill remarked (On Liberty, chapter 2).

What if we leave out condition (3), and suppose that while serious loss would follow from failing to act on the consensus view if it were correct, there would be no serious loss from acting on the consensus view if it were incorrect?

We might take the attitude of Pascal's Wager: we might as well act on the consensus view anyway. Then it might seem that opposition to the consensus view would be reprehensible, if it would be likely to hinder that desirable course of action.

However, even assuming that action on the consensus view would be the only sensible thing to do, and that opposition might hinder that course of action, it would not follow that opposition would be reprehensible. Opposition could still fortify belief in the consensus view, as suggested by Mill, if the opposer's arguments were found wanting. And if we were to adopt Clifford's attitude, we would want opponents of the consensus to be as active as they could be, in order to root out any mistaken beliefs that might happen to be held by the majority. That would be so, even if retention of the beliefs in question would not lead to any immediate adverse consequences, whether they were mistaken or correct. It would be so, both because an accumulation of erroneous beliefs, individually harmless, might have adverse consequences long after the beliefs were acquired, and because truth is something that is to be valued in itself.

Tricks of presentation

Yesterday, I saw the new David Bowie exhibition at the Victoria and Albert Museum. The exquisitely curated sequence of pieces of music, video clips, costumes, and other artefacts, demonstrates the power of presentation, far more than a single concert would do. I suppose the reason is that when we see contrasting tools of presentation, used in different concerts, we become aware of what each tool does, because it does not do quite the same as the corresponding tool in the next display. But we can remain carried away by each act of a pop star, because we know it is only an act. It does not profess to convey anything much about the Universe.

Now suppose we saw an exhibition of papal inaugurations and other grand religious ceremonies, and we therefore became more aware of how the tools of presentation worked in each one. Those who are currently carried away by such shows might cease to be so, because when something that is supposed to be more than an act, and to represent a point of contact with some profound truth about the Universe, is revealed to be shot through with tricks of presentation, doubt must be cast on the supposed profound truth. It should not need those tricks. And if the supposed profound truth is discarded, the show ceases to be a piece of fun, and is reduced to a charade. It cannot survive the loss of its raison d'être.

It is tempting to define an epistemic virtue, and its corresponding vice, in the following terms.

1. Suppose that there is some information.
2. The information might be presented in a variety of ways.
3. We shall only consider ways that would allow the subject to grasp the information.
4. The subject may form a view on the information's truth, or on its trustworthiness.
5. A propensity to form the same view, regardless of the way in which the information was presented, would be an epistemic virtue.
6. A propensity to form different views, depending on the way in which the information was presented, would be an epistemic vice.

This virtue and vice would come close to the virtue of scepticism (in the sense of being appropriately critical, not the Pyrrhonian sense or anything close to that sense) and the vice of gullibility, but the focus here is on the method of presentation, not on any other ways in which people might avoid being led astray, or might be led astray.

We could not test for the virtue, or the vice, in a given individual, by presenting the same information to him or her several times, in different ways, because the individual would remember previous presentations. We might use repeated presentation, with different forms of presentation being used in various orders, on a large sample of people, to test for the effectiveness of different methods of persuasion across the population as a whole, but that would be a different exercise.

We might note whether an individual was in general susceptible to the vice, by seeing whether he or she tended to accept the content of adverts or of propaganda. But our conclusions would probably be impressionistic, rather than based on a rigorous consideration of evidence. Indeed, if someone comes along with a test that purports to tell us whether a given individual is, or is not, uniformly susceptible to persuasion through the use of tricks of presentation, we should be sceptical of that claim.

Artificial intelligence and values

An article in the latest issue of Cambridge Alumni Magazine (issue 68, pages 22-25, but 24-27 of the version readable online), discusses the work of the Centre for the Study of Existential Risk. Huw Price, the Bertrand Russell Professor of Philosophy at Cambridge, takes us through some of the issues.

The magazine is available here:

http://www.alumni.cam.ac.uk/news/cam/

and some information about the Centre is available here:

http://cser.org/index.html

I found this comment by Huw Price particularly striking:

"It is probably a mistake to think that any artificial intelligence, particularly one that just arose accidentally, would be anything like us and would share our values, which are the product of millions of years of evolution in social settings."

This is an interesting thought, as well as a scary one. It leads us to reflect on what it would be for an artificially intelligent entity to have alternative values.

I shall start by considering what values do. I take it that they are, or provide, resources that allow us to decide what to do, when the choice is not to be made on purely instrumental grounds. That is, the choice is not to be made purely by answering the question, "What is the most efficient way to achieve result R?". The choice as to what to do might be one that was not to be made on purely instrumental grounds, either because of the lack of a well-defined result that was definitely to be achieved, or because it was not clear that all of the possible means, drawn from the feasible range, would be justified by the ends.

It would be possible for some artificially intelligent entity not to have any values at all, even if it could always decide what to do. It might choose both its goals and its methods by reference to some natural feature that we would regard as very poorly correlated, or as not correlated at all, with any conception of goodness. For example, it might always decide to do what would minimize entropy on Earth (dumping the corresponding increase in disorder in outer space, since it could not evade thermodynamics). We may not care about outer space, but we know that the minimization of entropy in our locality is not always a good ethical rule. When such a decision procedure failed to give clear guidance, the system could fall back on a random process to make its choices, and we would be at least as dissatisfied with that, as with the entropy rule.

The entropy example shows that there are things that do the job that I have just assigned to values, allowing entities to make decisions when the choice is not to be made on purely instrumental grounds, but that do not count as values. It is a nice question, how broad our concept of values should be. But we probably would have to extend it to naturalistic goals such as the maximization of human satisfaction, in order to have an interesting discussion about the values that artificially intelligent entities might have, in the context of the current or immediately foreseeable capacities of such entities. That is, we would have to allow commission of the naturalistic fallacy (supposing it to be a fallacy). It would be a big step, and one that would take us into a whole new area, to think of such entities as having the intuitive sense of the good that G E Moore would have had us possess.

We not only require the possessor of values to meet a certain standard in the content of its values, the standard (whatever it may be) that tells us that a purported value of entropy minimization does not count. We also require there to be some systematic method by which it gets from the facts of a case, and the list of values, to a decision. Without such a method, we could not regard the entity as being able to apply its values appropriately. It would, for practical purposes, not have values.

Sometimes the distinction between values and method is clear: honesty and courage are values, and deciding what action they recommend in a given situation is something else. At other times, the distinction is unclear. A utilitarian has the supreme value of the promotion of happiness, and a method of decision - the schema of utilitarian computations - that is intimately bound up with that value. From here on, I shall refer to a system of values, meaning the values and the method together.

Now suppose that an artificially intelligent entity had some decision-making resources that we would recognize as a system of values, but that we would say was not one of our systems of values, perhaps because we could see that the resources would lead to decisions that we would reject on ethical grounds, and would do so more often than very rarely. What would need to be true of the architecture of the software, for the entity to have that system of values (or, indeed, for it to have our system of values)?

One option would be to say that the architecture of the software would not matter, so long as it led the entity to make appropriate decisions, and to give appropriate explanations of its values on request.

That would, however, give a mistaken impression of latitude in software design. While several different software architectures might do the job, not just any old architecture that would yield appropriate decisions and explanations most of the time, would do.

The point is not that a badly chosen architecture, such as a look-up table that would take the entity from situations to decisions, would be liable to yield inappropriate decisions and explanations in some circumstances. An extensive look-up table, with refined categories, might make very few mistakes.

Rather, the point is that when the user of a system of values goes wrong by the lights of that system - falls into a kind of ethical paradox - we expect the conflict to be explicable by reference to the system of values (unless the conflict is to be explained by inattention, or by weakness in the face of temptation, and an artificially intelligent entity should be immune from both of those). That is, a conflict of this kind should shed light on a problem with the system of values. This is one reason why philosophers dream up hard cases, in order to expose the limits of particular sets of values, or of general approaches to ethics: the hard cases generate ethical paradoxes, in the sense that they show how decisions reached in particular ways can conflict with the intuitions that are generated by our overall systems of values. If the same requirement that conflicts should shed light on problems with systems were to hold for the use that an artificially intelligent entity made of a system of values, the software architecture would need to reflect the structure of the system of values, and in particular the ways in which values were brought to bear in specific situations. Several different architectures might be up to the job, but not just any old architecture would do.

Given a systematic software architecture, for a system of values that we would regard as unacceptably different in its effects from our own system of values, we can ask another question. Where would we need to act, to correct the inappropriateness?

We should not simply make superficial corrections, at the point where decisions were yielded. That would amount to creating a look-up table that would override the normal results of the decision-making process in specified circumstances. That would not really correct the entity's system of values. It would also be liable to fail in circumstances that we did not anticipate, but in which the system of values would still yield decisions that we would find unacceptable.

We would need to make corrections somewhat deeper in the system. Here, a new challenge might arise. As noted above, it is possible for values and methods of decision to be intertwined. In such value systems in particular, and perhaps also in value systems in which we do naturally and cleanly separate values from methods, it is perfectly possible that the software architecture would have intertwined values and methods in ways that would not make much sense to us. That is, we might look at the software, and not be able to see any natural analysis into values and methods, or any natural account of how values and methods had combined to produce a given overall decision-making system.

This could easily happen if the software had evolved under its own steam, for example, in the manner of a neural net. It could also happen if the whole architecture had been developed entirely under human control, but with the programmers thinking in terms of an abstract computational problem, rather than regarding the task as an exercise in the imitation of our natural patterns of thought about values and their application. Even if the intention were to imitate our natural patterns of thought, that might not be the result. The programming task would be vast, and it would involve many people, working within a complex system of software configuration management. It is perfectly possible that no one person would have a grasp of the whole project, at the level of detail that would be necessary to steer the project towards the imitation of our patterns of thought.

A significant risk may lurk here. If we become aware that artificially intelligent entities are operating under inappropriate systems of values, we may be able to look at their software, but unable to see how best to fix the problem. It might seem that we could simply turn off any objectionable entities, but if they had become important to vital tasks like ensuring supplies of food and of clean water, that might not be an option.

Reasonableness

An English jury, in a criminal trial, must decide whether the prosecution has shown, beyond reasonable doubt, that the accused committed the crime. Normally, all 12 jurors must agree, but judges sometimes allow verdicts agreed on by only ten jurors.

Suppose that a jury starts its deliberations, and after some discussion, takes a vote. Eight say that the prosecution has shown guilt beyond reasonable doubt, but four say that it has not. All of these opinions have been reached by considering only the evidence presented in court, and comments by jurors on that evidence. After more discussion, it becomes clear that no juror is going to change his or her opinion, so long as only those things are considered.

Jurors might then consider the pattern of voting. Any one of the eight might reason as follows.

"Some people in the jury room think that the prosecution has not discharged its burden of proof. There is no ground to think that they are not reasonable people, and in any case, it is unlikely that one would get four unreasonable people among 12 randomly chosen people, although one might get one or two. If the prosecution had discharged its burden of proof, they would probably have been convinced, because reasonable people generally hold reasonable views on such questions. They are not convinced, so I should change my view and vote for acquittal."

(It might be thought that there would be a mirror-image argument for the four: "Eight apparently reasonable people have concluded that the prosecution has discharged its burden of proof, and they would not have concluded that if it had not, so I should change my view". But that argument should be excluded by the fact that the burden of proof is on the prosecution. Doubt trumps certainty. The views of the four could plant doubts in the minds of the eight, but the views of the eight could only plant doubts over whether to acquit in the minds of the four, and a doubt as to whether to acquit is not enough to convict.)

Clearly, this reasoning is not always followed in practice. If it were, we would never get deadlocked juries, because the reasoning would transform deadlock into acquittal. The psychological explanation may well be that at least some jurors think their job is to decide whether the accused is guilty, rather than to decide whether the prosecution has shown guilt beyond reasonable doubt. A seemingly more respectable reason would be that jurors made up their minds individually, on the basis of the evidence presented and other jurors' comments on that evidence, and did not consider that their views should be influenced by the views of other jurors. And yet, we may ask whether that reason really would be respectable. It would imply that each juror should decide on the basis of the standard of reasonableness of doubt that he or she would use when he or she had no-one else's guidance available, rather than on the basis of a standard of reasonableness of doubt that had been tested by reference to the conveniently available sample of 11 other people in the jury room. Would not such a test be likely to improve one's grasp of the appropriate standard? The concept at work should be as objective as possible: doubt that is reasonable, not doubt that an individual, with his or her foibles, might happen to consider reasonable.

Occasionally, comparable considerations are tackled explicitly in legislation. The UK is about to have a general anti-abuse rule put into its tax legislation. Assuming that the legislation follows the draft that was published in December 2012, the use of a tax avoidance scheme will only be caught by this new rule, removing the anticipated tax saving, if that use "cannot reasonably be regarded as a reasonable course of action in relation to the relevant tax provisions". (Even if the use of a scheme is not caught by the new rule, it may very well be caught by other rules.) For the text and commentary, see GAAR Guidance Part A, 11 December 2012, section 5.2, available here:

http://www.hmrc.gov.uk/budget-updates/11dec12/gaar-guidancepart-a.pdf

This is known as the double reasonableness test. If there are reasonable views on both sides, both that the use of a scheme was a reasonable course of action and that it was not, then use of the scheme will not be caught. It is natural, and very likely to be correct, to determine whether a view is reasonable by considering whether it is supported by arguments that a substantial proportion of people who are well-informed about the subject matter would consider to be reasonable, and whether there is an absence of any manifest objection that would lead most well-informed people to reject the view.

We should note a subtlety here. The legislation focuses on the reasonableness of a view, not of people who hold it. A reasonable person may happen to hold some unreasonable views. As the official commentary points out, it is not enough simply to produce an eminent lawyer or accountant, who states that a course of action was reasonable. (Ibid., paragraph 5.2.2.2)

If, however, a substantial number of eminent lawyers and accountants stated that a course of action was reasonable, it would be hard to maintain that this view was unreasonable. When we test for reasonableness, as distinct from correctness, the number of votes among experts carries some weight. (It may also carry weight in relation to correctness, but in a rather different way, and a minority of one can be correct.)

This reflects the fact that reasonableness is a normative concept that is directly related to the adoption of views, in a way that, where there is real debate among experts, correctness is not. What should you do? In fields in which there is such a thing as expertise, and in which you are not yourself an expert, you should limit yourself to adopting reasonable views, or suspending judgement. How can you avoid adopting unreasonable views? See what the experts think, and limit yourself to views that are adopted by decent numbers of experts (or to suspension of judgement).

Correctness of views is an aspiration, at least in relation to views of a type that have any prospect of being classified as correct or incorrect, but in areas where there is real debate among experts, views do not carry labels, "correct" and "incorrect", so the concept of correctness does not regulate the conduct of non-experts directly. We can only adopt strategies that are likely to lead to the avoidance of incorrect views, like limiting ourselves to reasonable views, or making ourselves experts and studying the evidence ourselves.

Artificial brains

The Human Brain Project aims to give us a computer simulation of the human brain, or at least to work towards that goal. Plenty of people are sceptical about the feasibility of the project. But there are also ethical questions. Some of them are mentioned on the project's website, here:

http://www.humanbrainproject.eu/ethics.html

The issues mentioned relate to what people might do, among, with and to other human beings, having learnt in detail how real human brains worked. Even if the simulation did not, at the neuronal level, work in the same way that actual brains worked, it could still mimic the brain at a larger scale, for example the level of processing ideas, in ways that would, for example, help political propagandists to work more effectively.

There is, however, another issue, related to the simulation itself. What, if anything, would make the simulation a moral client, so that ethical concerns would bear on a decision to modify its thoughts by direct intervention (rather than by talking to it and inviting it to accept or reject some new idea), or would bear on a decision to switch it off?

It would not, we may assume, have a power of action, or a power to move around the world. One might therefore argue that it would not have a well-grounded sense of self (compare some of the arguments in Lucy O'Brien's book, Self-Knowing Agents). But it could still have the internal configuration that would correspond to a sense of self, a configuration that was artificially engineered by the researchers, as if it had had a history of action. I assume here that such a sense could be retained, and would not be lost over a long period without action, just as a human being who became totally paralysed and immobile could retain a sense of self. The artificial brain would, however, need to think of itself as one who had become paralysed, or would have to be fed the delusion that it was in an active body in the world, or would have to remain puzzled about its sense of self. Given the nature of the project, it is most likely that the artificial brain would be fed the delusion of being in an active body.

Likewise, the artificial brain could have artificially engineered senses of pain and of fear, like those that were appropriate to a being which moved around in the world and needed to act to distance itself from dangers, and that had been evolved in the species, or developed in the individual, through encounters with dangers.

The sense of self, and the feelings, would have dubious provenance. If we were to think that such senses were given their content by the external reality that grounded them - a kind of meaning externalism - we would have to think of them as not having the content that they had for us. That might let us off recognizing the artificial brain as a moral client, but it seems unlikely that it would do so. Even a convinced meaning externalist would, after all, hesitate to turn off the nutrients that fed human brains which had been put in vats years ago, and had been plugged into the usual delusive inputs for long enough for the presumably externally grounded meanings of their thoughts to have changed.

Moreover, while the sense of self might be based on a fabrication, it is not clear that the sense of self would itself be unreal. It would be even harder to show that the artificial brain's theory of mind, used in its encounters with people, was unreal. And the researchers would be very likely to apply their own theories of mind and intentional stances to the artificial brain. At least, some of them would, entering into social relationships that would, between human beings, stimulate moral concern, while other researchers measured the results in order to understand how real human brains behaved in encounters with other people. Possession of a theory of mind looks like something that ought to make the possessor a moral client. It has certainly been argued to have that consequence in relation to great apes other than human beings, although the extent to which they really have a theory of mind is controversial.

On the other side, there would be arguments that the simulation would just be a large piece of software, that it was not even fully integrated into a single person because it was shared between several computers (although this might reduce the accuracy of the simulation, because large-scale co-ordinating electrical activity does seem to matter to consciousness), and that it would not even know if it were modified, slowed down or turned off - although modifications, and processing speed adjustments, would have to be made carefully in order not to leave traces of the old state or speed that would give the game away.

The software point has strength if we think that when an entity is not intrinsically dependent on its hardware, that makes it less of a moral client. We are intrinsically dependent on our hardware, or at least, we are now, and will remain so until we work out how to copy the contents of a brain onto some computer-readable medium. Even then, it would matter which body someone was, and what the history of that body had been; that degree of hardware-dependence would remain.

The point about lack of awareness of changes needs to be elaborated. It is utterly wrong suddenly to kill someone, even without their knowledge or any kind of anticipation. It is also wrong to manipulate people's thoughts or attitudes, in the way that politicians, spin-doctors and the advertisers of products do, without people's awareness of what is going on, rather than using open and rational argument. If it were to be acceptable to turn off an artificial brain, the reason would have to go beyond its own lack of anticipation of this fate. It would be likely to have something to do with the fact that a piece of software would not have existed within a caring community. It would have had no relatives to mourn it, and it would never have had a potential beyond what its creators had planned for it. (It would have had a potential beyond what its creators had coded: one of the features of neural nets is that they develop in their own way.) But that move in the argument is dubious, because the question is that of whether the software should have been surrounded by a caring community, one that regarded it as a moral client. Something similar could be said about the far lesser offence of manipulation. This might look acceptable, because the software would only ever have had the potential that its creators had planned. But whether that ought to have given them ownership of its mind is the point at issue.

I remain unclear as to whether a full simulated brain should be regarded as a moral client. I predict that if its creators did not so regard it, the rest of us would not reprove them. But they might reprove themselves for turning it off, and then comfort themselves with the thought that they had kept the final software configuration, so that it could be re-awoken at any time.

Dostoevsky on deciding what to do

There is an intriguing view of human decision-making and freedom in Dostoevsky's Notes from Underground, part 1, chapters 7 and 8. Here, I shall analyse an argument from chapter 7.

Dostoevsky starts with a question. Why do we, again and again, knowingly and deliberately act in ways that are contrary to our own advantage? He promptly moves on to another question. What is a person's advantage? Then he claims that there is an advantage that cannot possibly be included in any catalogue of advantages.

The advantage that cannot be included in any catalogue is that of making an unfettered choice, in defiance of any careful computation of advantage. The argument may be reconstructed as follows. (This reconstruction goes beyond what Dostoevsky says, in order to secure the argument against some obvious logical objections.)

1. Suppose that a person, D, is aware of the contents of a supposedly complete set, S, of advantages to him or her, along with information about their relative importance, about how to obtain the advantages, and about the possibilities for obtaining various combinations of them. "Advantages to D" has a broad meaning. It may include advantages of benefiting others, at no obvious gain to D. There is no suggestion that D need be selfish in making the best possible selection of advantages from S.

2. D can now make a careful computation of what to do, in order to maximize the net advantage to D.

3. D can also exercise freedom, by going against the result of the computation.

4. The exercise of freedom is in itself an advantage to D, but it cannot be the result of the computation, otherwise it would not be an assertion of D's freedom. D could freely decide to act in accordance with the result of the computation, but that would not be the kind of unfettered freedom that is required here. It would not assert D's ability to live unconstrained by such computations.

This argument does leave space for action in defiance of the result of the computation to be included in S. But defiance could not coherently appear as all or part of the result of the computation. Its inclusion in S would therefore be idle.

Suppose, first, that the computation produces a single recommendation, to act in defiance of the result of the computation. Compliance with the recommendation would amount to defiance of it, and defiance of it would amount to compliance with it. (There would be the additional, substantial, difficulty that D would not know what to do. "Act in defiance of a recommendation to eat healthily", would give D an idea of some specific action. "Do not do what this sentence tells you to do", would give no idea of any specific action.)

Now suppose that the computation produces several recommendations, say "Eat healthily", "Move to another city", and "Act in defiance of the result of the computation". If we read this list as a conjunction, as I think should, we find that D cannot comply with all conjuncts. Suppose that D eats healthily and moves to another city. Then if D complies with the final conjunct, it can only be by defying that conjunct, since that is the only remaining way to break the terms of the conjunction. If, on the other hand, D defies the final conjunct, then D must comply with the whole conjunction, which must mean complying with the final conjunct, as well as with the other two.

The one apparently coherent option would be to defy either or both of the first two conjuncts, and thereby comply with the third. But on closer inspection, we can see that this would not work either. The reason is that it would be known in advance that "Act in defiance of the result of this computation" would amount to "Discard at least one of the specific prescriptions". Given that acting in defiance of the computation was considered to be an advantage, a member of S, this discard would be required in order to yield the optimal solution, if the prescription to act in defiance of the result were to be part of the result. Therefore, the discard of at least one of the specific prescriptions would form part of the calculation, before the result was given. (The prescriptions to be discarded might be chosen by some rule, or at random.) But then the result would be a conjunction of the remaining specific prescriptions and the prescription to act in defiance of the result. Again, at least one of the specific prescriptions would have to be discarded, in order to achieve the optimal result while still keeping the prescription to defy as part of that result, and this too would have to form part of the calculation. We would continue until only the prescription to act in defiance of the result was left. But as already noted, that would lead to incoherence.

We may therefore conclude that while the prescription to act in defiance of the result could be included in S, contrary to what Dostoevsky asserted, it could not coherently feature in a prescription of what to do in order to maximize advantage, so its inclusion in S would be idle.

Relics and agency

For many years, I have made a point of visiting the graves of philosophers, writers, artists, composers, mathematicians and scientists. I have made substantial detours for major philosophers. But a short walk from home today gave me pause for thought.

The walk was to St Paul's Church, Covent Garden, which is particularly associated with actors. I went there in search of Samuel Butler (Hudibras), Samuel Butler (Erewhon), and Janet Webb (the lady who comes down at the end, from Morecambe and Wise). I found none of them. Tombstones were too worn, and smaller markers had disappeared or become hidden in undergrowth. But the church is full of fresh, clear memorial tablets to many well-known actors. The bones or ashes of most of them are, so far as I know, elsewhere. The tablets may remind those who knew those commemorated, but for the rest of us, they do not seem to count anywhere nearly as much as the graves themselves would count. Why is that? Bones and ashes are not people, and after a few decades in damp soil, nothing will be left, as was found when an attempt was made to dig up relics of John Henry Newman in 2008 (although there is controversy about exactly what happened there).

One explanation of the magic of a real grave would be the existence of direct material connections between the living person, the fresh body and whatever now remains. But there is an alternative. This would be to say that what is important is not that the remaining matter was once part of the person, placing the emphasis on mereology, but that it was once intimately bound up with the person's activity, placing the emphasis on agency.

Why should we consider this option? One reason is that a person matters to those of us who did not know him or her because of what he or she did, so if things matter, it should be because of their roles as instruments of agency. (I use "instruments" in a broad sense, so as to accommodate both the view that our limbs are outer tools of an inner agent, and the view that an action is performed by the body as a whole, with no part of it being a mere tool of some inner agent.)

Another reason is that it would allow us to merge an account of the magic of graves with an account of the magic of writers' notebooks, artists' palettes, and the other items that one often finds in museums. Those items were also instruments of their owners' agency. Indeed, if one were to follow the line of thinking of Andy Clark, they would be extensions of the person, rather than mere external tools (see, for example, his paper "Reasons, Robots and the Extended Mind", Mind and Language, volume 16, number 2, March 2001).

A third reason is that a focus on agency would allow us to limit the extension to items in museums, so that it stopped at a sensible place. Items that anyone might happen to own, such as walking sticks or items of clothing, would be excluded from being legitimate possessors of magic. We would not become like Chick in L’Écume des jours, who obsessively collected anything associated with Jean-Sol Partre.

It might, however, allow us to continue to find magic in a great person's home. Home is where creative work is done, influenced by the atmosphere, the surrounding streets or fields, and the view. There are some things that are not directly instruments of agency, but that are so bound up with what someone did, that an agency-based approach to relics could accommodate them.