The badness of non-intentional harming

Consider a trolley problem where on both tracks there is exactly one innocent stranger. Alice is driving the trolley. If she does nothing, the trolley will head down the left track. But the right track will get Alice to her destination three minutes sooner. Alice redirects.

It seems that Alice did something wrong. Yet, why? We can say that she intended to save the person on the left track and get to her destination faster, and did not intend to kill the person on the right track. What went wrong?

One option is this. In the proportionality condition on Double Effect, we need that the outcome chosen have a significantly better consequence than the alternative, and three minutes (normally) is not significant.

But that’s probably not right. There are times when it is permissible to redirect a trolley even when the outcome is a bit worse. For instance, suppose that we have a trolley setup with one person on each track, but things are such that if the trolley hits the person on the right track, the death will be a bit more painful. The trolley is controlled by the person on the right track. It seems obvious that the person on the right track is permitted to redirect the trolley to the right even though the outcome is a bit worse.

Maybe the issue is this. Even though it’s not always wrong to become the non-intentional cause of a grave harm to someone, we have moral reason to avoid becoming such a cause. This fits with our intuitions: we feel really bad when we become such a cause. Murray Leinster’s first novel Murder Madness is all about the horror of a drug that makes one involuntarily kill people (I won’t recommend the novel because of a number of pieces of outrageous racism).

This makes sense from an Aristotelian point of view. For a social organism, helping members of the group is a part of flourishing. This is true for animals that are not moral agents. A meerkat sentinel that saves the group by warning of a danger is thereby flourishing. This is even true in the case of non-intentional cooperative activity. A slime mold that, as part of a stalk, enables reproduction by slime molds that are part of the fruiting body is thereby flourishing. It makes sense, thus, to think that for social organisms harming members of the group is contrary to flourishing whether or not one is morally responsible for the harm, and even when the harm is one that one is not intending.

Natural reasoning vs. Bayesianism

A typical Bayesian update gets one closer to the truth in some respects and further from the truth in other respects. For instance, suppose that you toss a coin and get heads. That gets you much closer to the truth with respect to the hypothesis that you got heads. But it confirms the hypothesis that the coin is double-headed, and this likely takes you away from the truth. Moreover, it confirms the conjunctive hypothesis that you got heads and there are unicorns, which takes you away from the truth (assuming there are no unicorns; if there are unicorns, insert a “not” before “are”). Whether the Bayesian update is on the whole a plus or a minus depends on how important the various propositions are. If for some reason saving humanity hangs on you getting it right whether you got heads and there are unicorns, it may well be that the update is on the whole a harm.

(To see the point in the context of scoring rules, take a weighted Brier score which puts an astronomically higher weight on you got heads and there are unicorns than on all the other propositions taken together. As long as all the weights are positive, the scoring rule will be strictly proper.)

This means that there are logically possible update rules that do better than Bayesian update. (In my example, leaving the probability of the proposition you got heads and there are unicorns unchanged after learning that you got heads is superior, even though it results in inconsistent probabilities. By the domination theorem for strictly proper scoring rules, there is an even better method than that which results in consistent probabilities.)

Imagine that you are designing a robot that maneouvers intelligently around the world. You could make the robot a Bayesian. But you don’t have to. Depending on what the prioritizations among the propositions are, you might give the robot an update rule that’s superior to a Bayesian one. If you have no more information than you endow the robot with, you won’t be able to expect to be able to design such an update rule. (Bayesian update has optimal expected accuracy given the pre-update information.) But if you know a lot more than you tell the robot—and of course you do—you might well be able to.

Imagine now that the robot is smart enough to engage in self-reflection. It then notices an odd thing: sometimes it feels itself pulled to make inferences that do not fit with Bayesian update. It starts to hypothesize that by nature it’s a bad reasoner. Perhaps it tries to change its programming to be more Bayesian. Would it be rational to do that? Or would it be rational for it to stick to its programming, which in fact is superior to Bayesian update? This is a difficult epistemology question.

The same could be true for humans. God and/or evolution could have designed us to update on evidence differently from Bayesian update, and this could be epistemically superior (God certainly has superior knowledge; evolution can “draw on” a myriad of information not available to individual humans). In such a case, switching from our “natural update rule” to Bayesian update would be epistemically harmful—it would take us further from the truth. Moreover, it would be literally unnatural. But what does rationality call on us to do? Does it tell us to do Bayesian update or to go with our special human rational nature?

My “natural law epistemology” says that sticking with what’s natural to us is the rational thing to do. We shouldn’t redesign our nature.

Relativism and natural law

Individual relativism and natural law ethics have something in common: both agree that the grounds of your ethical obligations are found in you. The disagreement, of course, is in how they are found. The relativist says that they are found in your subjectivity, in your beliefs and values that differ from person to person, while the natural lawyer thinks they are found in your human form, which is exactly like the human form of everyone else.

(Whether Kantianism shares this feature depends on how we read the metaphysics of rationality, namely whether our rationality as a genuine part of our selves, or as an abstraction.)

I think this commonality has some importance: it captures the idea that idea that we are in some sense morally beholden to ourselves rather than to something alien, something about which we could ask “Why should I listen to it?”

But I think in the end natural law does a better job being a non-alienating ethics. For we have good reason to think that my moral beliefs and values are etiologically largely the product of society around me and accidental features in my life. If these beliefs and values are what grounds my moral obligations, then my obligations are by and large the product of society and accident. (Think of the common philosophical observation that we do not choose our beliefs, but catch them like one catches a cold.) If I had lived in a different society with different accidental influences, I would have had different obligations on relativism. The obligations are, thus, largely the result of external and accidental influence on my cognition.

On the other hand, on natural law, my obligations are grounded in my individual human form which is my central and essential metaphysical constituent. Granted, I did not create this form for myself. But neither is it an accidental result of external influence—it defines me.

I think that as a society we feel that the variability of our individual beliefs and values makes us more autonomous if relativism is true. But once we realistically realize that this variability is largely due to external influence, our intuitions should shift. Natural law provides a more real autonomy.

Of course, on a theistic version of natural law, my form comes from God. Yes, but on orthodox Aristotelianism (which I am not sure I completely endorse) it is not an alien imposition, since I have no existence apart from that form.

Glitches in the moral law?

Human law is a blunt instrument. We often replace the thing that we actually care about by a proxy for it, because it makes the law easier to formulate, follow and/or enforce. Thus, to get a driver’s license, you need to pass a multiple choice test about the rules of the road. Nobody actually cares whether you can pass the test: what we care about is whether you know the rules of the road. But the law requires passing a test, not knowledge.

When a thing is replaced by (sometimes we say “operationalized by”) a proxy in law, sometimes the law can be practically “exploited”, i.e., it is possible to literally follow the law while defeating its purpose. Someone with good test-taking skills might be able to pass a driving rules test with minimal knowledge (I definitely had a feeling like that in regard to the test I took).

A multiple-choice test is not a terrible proxy for knowledge, but not great. Night is a very good proxy for times of significant natural darkness, but eclipses show it’s not a perfect proxy. In both cases, a law based on the proxy can be exploited and will in more or less rare cases have unfortunate consequences.

But whether a law can be practically exploited or not, pretty much any law involving a proxy will have unfortunate or even ridiculous consequences in far-out scenarios. For instance, suppose some jurisdiction defines chronological age as the difference in years between today’s date and the date of birth, and then has some legal right that kicks in at age 18. Then if a six-month-old travels to another stellar system at close to the speed of light, and returns as a toddler, but 18 years have elapsed on earth, they will have that the legal rights accruing to an 18-year-old. The difference in years between today’s date and the date of birth is only a proxy for the chronological age, but it is a practically nearly perfect proxy—as long as we don’t have near-light-speed travel.

If a law involves a proxy that does not match the reality we care about in too common or too easy to engineer circumstances, then that’s a problem. On the other hand, if the mismatch happens only in circumstances that the lawmaker knows for sure won’t actually happen, that’s not an imperfection in the law.

Now suppose that God is the lawmaker. By the above observations, it does not reflect badly on a lawmaker if a law involves a proxy that fails only in circumstances that the lawmaker knows for sure won’t happen. More generally, it does not reflect badly on a lawmaker if a law has unfortunate or ridiculous consequences in cases that the lawmaker knows for sure won’t happen. Our experience with human law suggests that such cases are difficult to avoid without making the law unwieldy. And while there is no great difficulty for God in making an unwieldy law, such a law would be hard for us to follow.

In a context where a law is instituted by God (whether by command, or by desire, or by the choice of a nature for a created person), we thus should not be surprised if the law “glitches” out in far-out scenarios. Such “glitches” are no more an imperfection than it is an imperfection of a helicopter that it can’t fly on the moon. This should put a significant limitation on the use of counterexamples in ethics (and likely epistemology) in contexts where we are allowing for the possibility of a divine institution normativity (say, divine command or theistic natural law).

One way that this “glitching” can be manifested is this. The moral law does not present itself to us as just as a random sequence of rules. Rather, it is an organized body, with more or less vague reasons for the rules. For instance “Do not murder” and “Do not torture” may come under a head of “Human life is sacred.” (Compare how US federal law has “titles” like “Title 17: Copyright” and “Title 52: Voting and Elections”, and presumably there are vague value-laden principles that go with the title, such as promoting progress with copyright and giving voice to people with voting.) In far-out scenarios, the rules may end up conflicting with their reasons. Thus, to many people “Do not murder” would not seem a good way to respect to respect the sacredness of human life in far-out cases where murdering an innocent person is the only way to save the human race from extinction. But suppose that God in instituting the law on murder knew for sure that there would never occur a situation where the only way to save the human race from extinction is murder. Then there would be no imperfection in making the moral law be “Do not murder.” Indeed, this would be arguably a better law than “Do not murder unless the extinction of humanity is at stake”, because the latter law is needlessly complex if the extinction of humanity will never be at stake in a potential murder.

Thus the theistic deontologist faced with the question of whether it would be right to murder if that were the only way to save the human race can say this: The law prohibits murder even in this case. But if this case was going to have a chance of happening, then God would likely have made a different law. Thus, there are two ways of interpreting the counterfactual question of what would happen if we were in this far-out situation. We can either keep fixed the moral law, and say that the murder would be wrong, or we can keep fixed God’s love of human life, and say that in that case God would likely have made a different law and so it wouldn’t be wrong.

We should, thus, avoid counterexamples in ethics that involve situations that we don’t expect to happen, unless our target is an ethical theory (Kantianism?) that can’t make the above move.

But what about counterexamples in ethics that involve rare situations that do not make a big overall difference (unlike the case of the extinction of the human race)? We might think that for the sake of making the moral law more usable by the limited beings governed by it, God could have good reason for making laws that in some situations conflict with the reasons for the laws, as long as these situations are not of great importance to the human species. (The case of murdering to prevent the extinction of the human race would be of great importance even if it were extremely rare!)

If this is right—and I rather wish it isn’t—then the method of counterexamples is even more limited.

The right can be derived from the good

There is a way to connect the right and wrong with the good and bad:

1. An action is right (respectively, wrong) if and only if it is noninstrumentally good (respectively, bad) to do it.

This is compatible with there being cases where it is bad for one to do the right thing. Thus, refraining from stealing the money that one would need to sign up for a class on virtue is right and noninstrumentally good, but if the class is really effective then stealing the money might be instrumentally good for one, though noninstrumentally ba.

I think (1) is something that everyone should accept. Even consequentialists can and should accept (1) (though utilitarian consequentialists have too shallow an axiology to make (1) true). But natural law theorists might add a further claim to (1): the left-hand-side is true because the right-hand-side is true.

The title of this post contradicts the title of another recent post, but the contents do not.

Variation in priors and community epistemic goods

Here is a hypothesis:

• It is epistemically better for the human community if human beings do not all have the same (ur-) priors.

This could well be true because differences in priors lead to a variety of lines of investigation, a greater need for effort in convincing others, and less danger of the community as a whole getting stuck in a local epistemic optimum. If this hypothesis is true, then we would have an interesting story about why it would be good for our community if a range of priors were rationally permissible.

Of course, that it would be good for the community if some norm of individual rationality obtained does not prove that the norm obtains.

Moreover, note that it is very plausible that what range of variation of priors is good for the community depends on the species of rational animal we are talking about. Rational apes like us are likely more epistemically cooperative than rational sharks would be, and so rational sharks would benefit less from variation of priors, since for them the good of the community would be closer to just the sum of the individual goods.

But does epistemic rationality care about what is good for the community?

I think it does. I have been trying to defend a natural law account of rationality on which just as our moral norms are given by what is natural for the will, our epistemic norms are given by what is natural for our intellect. And just as our will is the will of a particular kind of deliberative animal, so too our intellect is the intellect of a particular kind of investigative animal. And we expect a correlation between what a social animal’s nature impels it to do and what is good for the social animal’s community. Thus, we expect a degree of harmony between the norms of epistemic rationality—which on my view are imposed by the nature of the animal—and the good of the community.

At the same time, the harmony need not be perfect. Just as there may be times when the good of the community and the good of the individual conflict in respect of non-epistemic flourishig, there may be such conflict in epistemic flourishing.

I am grateful to Anna Judd for pointing me to a possible connection between permissivism and natural law epistemology.

The right cannot be derived from the good

Consider the following thesis that both Kantians, utilitarians and New Natural Law thinkers will agree on:

1. All facts about rightness and wrongness can be derived from descriptive facts, facts about non-rightness value, and a small number of fundamental abstract moral principles.

The restriction to non-rightness good and bad is to avoid triviality. By “rightness value” here, I mean only the value that an action or character has in virtue of its being right or wrong to the extent that it is.

I don’t have a good definition of “abstract moral principle”, but I want them to be highly general principles about moral agency such as “Choose the greater over the lesser good”, “Do not will the evil”, etc.

I think (1) is false.

Consider this:

2. It is not wrong for the government to forcibly and non-punitively take 20% of your lifetime income, but it is wrong for the government to forcibly and non-punitively take one of your kidneys.

I don’t think we can derive (2) in accordance with the strictures in (1). If a kidney were a lot more valuable than 20% of lifetime income, we would have some hope of deriving (2) from descriptive facts, non-rightness value facts, and abstract moral principles, for we might have some abstract moral principle prohibiting the government from forcibly and non-punitively taking something above some value. But a kidney is not a lot more valuable than 20% of lifetime income. Indeed, if it would cost you 20% of your lifetime income to prevent the destruction of one of your kidneys, it need not be unreasonable for you to refuse to pay. Indeed, it seems that either 20% of lifetime income is incommensurable with a kidney, or in some cases it is more valuable than a kidney.

If loss of a kidney were to impact one’s autonomy significantly more than loss of 20% of your lifetime income, then again there would be some hope for a derivation of (2). But whether loss of a kidney is more of an autonomy impact than loss of 20% of income will differ from person to person.

One might suppose that among the small number of fundamental abstract moral principles one will have some principles about respect for bodily integrity. I doubt it, though. Respect for bodily integrity is an immensely complex area of ethics, and it is very unlikely that it can be encapsulated in a small number of abstract moral principles. Respect for bodily integrity differs in very complex ways depending on the body part and the nature of the relationship between the agent and the patient.

I think counterexamples to (1) can be multiplied.

I should note that the above argument fails against divine command theories. Divine command theorists will say that about rightness and wrongness are identified with descriptive facts about what God commands, and these facts can be very rich and hence include enough data to determine (2). For the argument against (1) to work, the “descriptive facts” have to be more like the facts of natural science than like facts about divine commands.

The structure of morality

In physics, we hope for the following unification: there is a small set of simple laws, and all the rest of physics derives logically from these laws and the contingencies of the arrangement of stuff.

In ethics, a similar ideal has often manifested itself. While I have a hope for the ideal being realized in physics, I have come to be more pessimistic about the ideal in ethics. Instead, I think we can have a looser unificatory structure. We can have a multilevel hierarchy of more general laws, and then more specific laws that specify or implement the more general laws.

I suspect the looser structure is what we have in Aquinas’s Natural Law. At the highest level we have the general law that the good is to be pursued and the bad to be avoided. This is then specified into three laws about promoting the goods of existence, species-specific life and reason. These three laws, I think, are then further specified.

There is thus a structure to the moral law, but it is not a deductive structure. The higher level laws make the lower level laws fitting, but do not necessitate them.

A tale of two membranes

Suppse that I had a device that would cause a mild but sensible vibration in the nasal membranes of the person I pointed it at. Absent consent or a significant reason, it would be wrong to use this device on a stranger.

But the same is not true if we replace nasal membranes with the tympanic membrane: we routinely vibrate the tympanic membranes of strangers with neither consent nor significant reason, say when we ask a stranger on the street for directions.

In both cases one is inducing a physical change of arrangement of body parts in the other person without their consent. We may suppose that hedonically there is no difference: perhaps the vibration and the speech are both mildly unpleasant. The case can be tweaked so that the impact on autonomy is greater in either case (e.g., the unwilling listener may identify themselves as the sort of person who doesn’t listen to arguments) or so that it is equal.

It is tempting to say that we have a default consent to hearing others out. But default consents can be withdrawn, and we are permitted to vibrate tympanic membranes even against the express directions of their possessor. If during an argument someone says “I don’t want to hear another word!” it is not morally wrong to respond verbally nonetheless.

This implies that the need for consent does not supervene on hedonic or autonomy facts. It depends on details of the intervention that go beyond these.

The fact that in my thought experiment an apparatus is used in the nasal but not the aural case is not relevant. If one speaks through a speech generating device, as famously Hawking did, one is no less permitted to vibrate strangers’ tympanic membranes with the speech. And it would be just as wrong to go up to strangers and blow air into their nostrils in order to vibrate their nasal membranes as to use a device.

So what is the difference?

The difference, I think, is that it is a part of the proper function of the tympanic membrane to receive speech from random strangers, whether one consents to this or not, while the nasal membranes have no such proper function. It is as if our human nature gives permission to others to speak to us, but does not give such a permission for nasal membrane vibration.

I think this is difficult to account for in anything other than natural law or divine command ethics.

A simple moral preference circle with infinities

Here is a simple moral preferability circle. Suppose there are infinite many human strangers numbered ..., −3, −2, −1, 0, 1, 2, 3, ... all of whom, in addition to two cats, are about to drown. Consider these options:

A. Save the strangers numbered 0, 1, 2, ....

B. Save the strangers numbered −1, −2, −3, ... and one cat.

C. Save the strangers numbered 1, 2, 3, ... and both cats.

Option B beats Option A: If we had to choose between strangers 0, 1, 2, ... and strangers −1, −2, −3, ..., we should clearly be indifferent. Toss in the cat, and now it looks like we have a reason to save the second set of strangers.

Option C beats Option B: If we had to choose between strangers −1, −2, −3, ... and strangers 1, 2, 3, ..., we should be indifferent. But now observe that in Option C one more cat is saved, and it sure looks like we should go for C.

Option A beats Option C: Option A replaces the two cats with stranger 0, and surely it’s better to save one human over two cats.

If you don’t think we have moral reasons to save cats, replace saving the cats from drowning with saving two human strangers from ten minutes of pain.

I am now toying with an intuitively very appealing solution to problems like the above: we have no moral rules in such outlandish cases. I think this can be said on either natural law or divine command theory. On natural law, it is unsurprising if our nature does not provide guidance in situations where we are far from our natural environment. On divine command theory, why would God bother giving us commands that apply to situations so far from ones we are going to be in?

Divine command, natural law and arbitrariness

People often levy an arbitrariness objection against divine command theory:

1. If God simply chooses what we ought, why did he choose to command kindness rather than cruelty?

It occurs to me that an advocate of theistic natural law probably cannot levy the arbitrariness object. For there is a structurally very similar question about theistic natural law:

2. If God simply chooses which natures to create, why did he choose to create beings with our basic physical structure and a nature that requires kindness rather than beings with our basic physical structure but a nature that requires cruelty?

It might be retorted that logical space does not contain a nature that specifies cruelty and yet the same basic physical structure as ours. This is plausible to me, but the main reason to doubt that there could be such a nature is some theistic story such as that all natures are ways of imitating God, and it is incompatible with divine goodness that he be imitable in such a cruel way. And this, in turn, is quite parallel to the standard divine command response to (1), that it is incompatible with divine goodness that he command cruelty to beings like us.

I think theistic natural law does have advantages over divine command theory. But a better resolution to the arbitrariness objection does not seem to be one of these advantages.

Theism and Natural Law

One occasionally wonders what theism adds to Natural Law ethics. Here is one example.

• Q1: Why are artistic endeavors good?

Here, Natural Law answers by itself, without any help from theism:

• A1: Because they fulfill the human nature.

We can ask another question:

• Q2: Why do artistic endeavors fulfill the human nature?

Again, Natural Law answers by itself in a not very informative way:

• A2: Because necessarily the human nature teleologically directs its possessors to artistic endeavors.

But we can now ask a different question:

• Q3: Why are there beings with a nature that teleologically directs its possessors to artistic endeavors?

Natural Law by itself has no answer. Theism can go on to answer Q3:

• A3: God created beings with such a nature because artistic endeavors imitate God, who is the Good Itself.

One might say that Q3 is an etiological rather than normative question, and hence lies beyond the scope of value theory. But A3 also answers a value-theoretic variant of Q3:

• Q3a: What is it about artistic endeavors that makes them apt for being intrinsically good for a being, apt for being the telos of a nature?

To see the force of Q3a, imagine that we meet aliens and they spend a lot of time and energy on some activity that does not seem to conduce to or constitute any biological end of theirs, and does not seem to promote any end that we can understand. We ask the aliens about why they do this activity, and they say: “It’s good for us in and of itself, and our observation of your culture shows that you have no concept of this type of good.” They are otherwise smart and morally sensitive, so we trust that the activity is good for them, that it is a telos of their nature.

But even after we have learned that the activity is a telos of their nature and hence intrinsically good for them, we would be puzzled by the activity, and what makes it apt for being a good for them. A theistic story about how this good imitates God provides an answer to this kind of a question.

The question suggests, too, that not everything is apt for being good for a being, that not everything is apt for being the telos of a nature. And that, too, seems right. It does not seem that one could have a being for which the production of ugliness or the promotion of the suffering of others is intrinsically good. But I think only a theist can say something like that.

Indeed, this last point suggests another way in which theism helps Natural Law. Consider this objection to Natural Law:

• Cruelty would be wrong even for beings whose nature it was to be cruel, but according to Natural Law, if a being’s nature were to be cruel, cruelty would be right for that being.

But the theist can do something to help with this: cruelty is just not the sort of thing that a nature could aim at, since it is counterimitative of God. So the conditional about beings whose nature is to be cruel is a per impossibile one. And it is not surprising if strange results follow from impossible suppositions.

The inhumanity problem for morality

When a state legislates, it often carves out very specific exceptions to the legislation. Sometimes, of course, one is worried that the exceptions are a sign that the legislators are pursuing special interests rather than the common good, but sometimes the exceptions are quite reasonable. For instance, you shouldn’t possess child pornography… except, say, if you are involved in the law enforcement process and need it as evidence to get the child pornographers. There is something ugly about carving out exceptions, but the point is to make society work well rather than make the laws elegant. Special-case clauses seem to be unavoidable in practice, given the messiness and complexity of human life. Elegant exceptionless legislation—with some important exceptions!—is apt to be inhuman.

I kind of wonder if an analogous thing might not be true in the case of morality, and for the same reason, the messiness and complexity of human life. Could it be that elegant exceptionless moral laws would necessarily have to be inhuman?

What solutions are available to this problem?

Well, we might just dig in our heels, either optimistically or pessimistically.

The optimistic version says: yes, we have elegant exceptionless moral laws, and they do work well for us. One way of running the optimistic variant is to make the moral laws leave a lot to human positive law. Thus, there are going to be exceptions to any prohibition of theft, but perhaps morality leaves the specification of this to the state. Or perhaps one could be really optimistic and have moral laws that do not leave a lot to positive law, but nonetheless they work. Act utilitarianism could be thought to provide this kind of solution, having a simple rule “Maximize utility!”, but its problem is that this rule is just wrong. Rule utilitarianism provides a nicer solution by having the elegant meta-rule “Do those things that fall under a utility-maximizing rule”, but I think the technical details here are insuperable.

The pessimistic variant says: yes, we have elegant exceptionless moral laws, and we’re stuck with that, even though it doesn’t work that great for us. That might be a better way to take act utilitarianism, but such pessimism is not a very attractive approach.

But what if we don’t want to dig in our heels? One could think that there are just brute (perhaps metaphysically necessary) facts about the moral rules, and many of these brute facts have specific exceptions: “Don’t lie, except to save a life or to prevent torture.” I think bruteness, and especially inelegant bruteness, is a last resort.

One might think that moral particularism is a solution: there are general elegant moral laws, but they all have unspecified exceptions. They say things like: “Don’t torture, other things being equal.” There is still a fact of the matter as to what to do in a particular situation, a fact that a virtuous agent may be able to discern, but these facts cannot be formulated in a general way, because any finite description of the particular situation will leave out factors that could in some other case trump the described considerations. There are exceptionless moral rules on such a view, but they are infinite in length. Unless some story is given as to where these infinite rules come from, this seems like it might be just an even worse version of the brute fact story.

Divine command theory, on the other hand, could provide a very nice solution to the problem, exactly analogous to the legislative solution. If God is the author of moral laws, he can legislate: “Thou shalt not kill, except in cases of types A, B and C.”

Natural law could also provide such a solution, at least given theism: God could select for instantiation a nature that has a complex teleology with various specific exceptions.

Where do I fall? I think I want to hold out for a two-level theistic natural law story. On one level, there is a simple, single and elegant moral rule embedded in our nature: “Love everything!” However, the content of that love is specified in a very complex way by our nature and by the circumstances (love needs to be appropriate to the specifics of the relationships). This specification is embedded in our nature by much more complex rules. And God chose this nature for instantiation because it works so well.

The coincidence between the right and the beneficial

One of the earliest and most important discoveries in Western philosophy was:

1. Doing the right thing is sometimes bad for you (in non-moral ways).

This precludes any easy reduction of morality to self-interest. But at the same time, the philosophers could see that:

2. Doing the right thing is usually good for you (even in non-moral ways).

This leads to an interesting problem that has occasionally been discussed, but not as much as one might hope:

3. What explains why acting morally well tends to be good for you (even in non-moral ways).

Living in accordance with one’s conscience, while having that conscience be well-formed, tends to lead to a kind attractive happiness that we can often see in people. There is that smile which reflects both a kindliness of nature and an inner joy. Why is there this harmony between the right and the beneficial?

If we were non-realists about morality, we might give an evolutionary explanation: our moral beliefs evolved to benefit us. But if we are realists about morality, then that only makes it puzzling: why is it that the true moral beliefs are the ones that tend to benefit us?

Divine command ethics has a plausible story grounded in God’s loving desire that we live under moral rules that are good for us. Natural law ethics has a different story: our natures are harmonious, and hence the many ends we have are mutually supportive. That story, of course, only shifts the problem to the more general question of the mutual support of our ends, and I suspect that this more general question cannot be answered without bringing in theism, either by positing that God is more likely to instantiate harmonious natures or that because created natures are way of participating in the God whose inner life is a harmony of love, they tend to be (or maybe even all are) harmonious.

Supererogation on Aristotelianism

The cheetah whose maximum speed is 40 mph is subnormal. The cheetah whose maximum speed is 58 mph is merely normal. The cheetah whose maximum speed is 80 mph is supernormal. An Aristotelian can accommodate these three judgments by saying that the form of the cheetah sets two things for the cheetah’s speed: a norm and a comparison. The norm specifies what is needed for being a healthy cheetah, and the comparison specifies what is a better speed than what. And the comparison can hold among instances that meet the norm, in which case the better instance is supernormal, and it can hold among instances that fail to meet the norm, too.

Having both a norm and a comparison for a type of good is especially important in the case of open-ended goods with a lower limit but no upper limit. Thus, no matter how much a human knows, knowing more would be better (in respect of knowledge). But there is such a thing as knowing enough to be a flourishing human knower. But we can also have a norm and a comparison in the case of things where there is an upper limit. Thus, a heart that is too small or too big is unhealthy. But is a range of healthy heart sizes (specified by the norm), and some of those sizes are healthier than others (specified by the comparison). Somewhere in that range there could even be (though vagueness and multidimensionality of comparison make that unlikely) a single optimal heart size.

What is true for dispositions (maximum speed) and physical arrangements is also true for operations. There is a normal cheetah running operation, a subnormal and a supernormal one. (Note that in some cases the supernormal one will be slower than the merely normal one, since sometimes energy needs to be conserved.)

The central Aristotelian insight I want to have in ethics is that just as there is proper function in the operation of the legs, there is proper function in the operation of the will. If so, then we would expect there to be a norm and a comparison: some instances of the will’s operation are normal and some are subnormal. And among the normal ones some will be better than others. Thus, in a case where multiple operations of the will are possible, that operation that is normal but better than another normal operation is supererogatory, while an operation that is normal but not better than another normal operation is merely permissible.

There is metaphysically nothing special about the supererogatory or the obligatory on the Aristotelian picture. They are just the instances of a general phenomena in the special case of the operation of the will.

Ethics and complexity

Here is a picture of ethics. We are designed to operate with a specific algorithm A for generating imperatives from circumstances. Unfortunately, we are broken in two ways: we don’t always follow the generated imperatives and we don’t always operate by means of A. We thus need to reverse engineer algorithm A on the basis of our broken functioning.

In general, reverse-engineering has to be based on a presumption of relative simplicity of the algorithm. However, Kantian, utilitarian ethics and divine command ethics go beyond that and hold that A is at base very simple. But should we think that the algorithm describing the normative operation of a human being is very simple? The official USA Fencing rule book is over 200 pages long. Human life is more complex than a fencing competition. Why should we think that there are fundamental rules for human life that can be encompassed briefly, from which all other rules can be derived without further normative input? It would be nice to find such brief rules. Many have a hope of finding analogous brief rules in physics.

We haven’t done well in ethics in our attempts to find such brief rules: the Kantian and utilitarian projects make (I would argue) incorrect normative claims, while the divine command project seems to give the wrong grounds for moral obligations.

It seems not unlikely to me that the correct full set of norms for human behavior will actually be very complex.

But there is still a hope for a unification. While I am dubious whether one can find a simple and elegant set of rules such that all ethical truths can be derived from them with no further normative input, there may be elegant unifying ethical principles that nonetheless require further normative input to generate the complex rules governing human life. Here are two such options:

• Natural Law: Live in accordance with your nature! But to generate the rules governing human life requires the further information as to what your nature requires, and that is normative information.

• Agapic ethics: Love everyone! But one of the things that are a part of love is adapting the form of one’s love to fit the the persons and circumstances (fraternal love for siblings, collegial love for colleagues, etc.), and the rules of “fit” are extremely complex and require further normative input.

Why do the basic human goods hang together as they do?

According to prominent Natural Law theories, the human good includes a number of basic non-instrumental goods, such as health, contemplation, truth, friendship and play. Now, there is a sense in which the inclusion of some items on the list of basic goods is more puzzling than the inclusion of others. There does not seem be anything deeply mysterious about the inclusion of health, but the inclusion of play is puzzling.

Yet there is an elegant metaphysical explanation of why these goods are included in the human good, and this explanation works just as well for play as for health:

1. The human good includes play (or health) because it is a fundamental telos in the human form to pursue play (or health).

This explanation tells us what makes it be the case that play is a basic human good. But I think it leaves something else quite unexplained. Compare to this the unhelpfulness of the answer

2. Because its molecules have a high mean kinetic energy

to the question

3. Why is my phone hot?

Now, in the case of my hot phone, the reason (2) is unhelpful is because when I am puzzled about my phone being hot, I am puzzled about something like the efficient cause of the phone’s heat, and (2) does not provide that.

That’s not quite what is going on the case of play. When we ask with puzzlement:

4. Why is play a basic non-instrumental human good?

we are not looking for an efficient cause of play being a basic human good. Indeed, it is dubious that there could even be an efficient causal answer to (4), since it seems to be a necessary truth that play is a basic human good, since this is grounded in the essential teleological structure of the human form. I think that when we ask (4), we are not actually clear on what sort of an explanation we are looking for—but if the puzzlement is the kind I am thinking about, the desired explanation is not the one given by (1).

We do become a bit less puzzled about play being a basic human good once it is pointed out to us how play promotes various other human goods like health and friendship. When we ask questions like (4), a part of what we are looking for is a story of how play hangs together with the other basic goods. If, as many Natural Lawyers think, there is a greatest human good (e.g., loving knowledge of God), then we hope that a significant part of the story will tell us how the good of play fits with that greatest good.

But now we have a curious meta-question:

5. Why is it that telling a story about how play hangs together with the other basic goods contributes to an answer to (4), given that play’s promotion of other basic goods seems to only make play be an instrumental good?

Here is another part of the story that helps with (5). Not only does engaging in play promote the other goods, but engaging play as an end in itself promotes the other goods more effectively. Playing Dominion with a friend purely instrumentally to friendship just wouldn’t promote friendship as effectively as playing in a way that appreciates the game as valuable in and of itself. Thus, a part of our story is now that it would be beneficial vis-à-vis the other goods if play were in fact to be non-instrumentally good, as then it could be pursued as an end in itself without this pursuit being a perversion of the will (it is, I take it, a perversion of the will to pursue mere means as if they were ends).

But it is still puzzling why even this enriched story is an answer to our question. The enriched story might make us wish that play were intrinsically good, but it doesn’t make play be instrinsically good. How does the enriched story help with our question, then?

I think that here is one of those places where Natural Law needs theism. It is a good thing for God to make beings whose basic goods exhibit unity in diversity. Thus, amongst the infinity of possible kinds of beings that could have been created, God chose to create beings with the human form in part because the basic goods encoded in the teleological structure of that form hang together in a beautiful way. God could have instead created beings where play was merely instrumentally good, but the teleological structure of such beings, first, wouldn’t exhibit the same valuable unity in diversity and, second, such beings would not as effectively achieve the other basic goods: for either they would be perversely pursuing a means as an end, or they would be missing out on the benefits of pursuing play as an end.

In other words, the story about how the goods hangs together provides a genuine answer to questions like (4) given God’s wise selection of the natures to be instantiated. It is difficult to see a plausible alternative story (here's an implausible one: there are no possible natures where goods don't hang together; here's another implausible one: we live in the best of all possible worlds). Thus, answering questions like (4) seems to call for theism.

Natural Law and the problem of contradictory moral norms

Given a Natural Law ethic, we could imagine a type of creature whose nature is such that even under normal circumstances, it is subject to incompatible moral obligations. We see such conflicts between creatures: the flourishing of the wolf is the languishing of the sheep. But we could imagine a being which has central instances of moral flourishing that also constitute central instances of moral languishing. Perhaps the being’s nature requires both mercy of it and a strict unrelenting justice. Or perhaps it requires both impartial justice and a favoring of kin.

Given that it is much easier to come up with conflicting systems of rules than with harmonious ones, we might well expect that the natures of moral creatures would have such conflicts of characteristic virtues. Thus, given Natural Law ethics, the absence of such general moral contradictions in us is something to be explained.

Given theistic Natural Law ethics, we can give two explanations. First, we could say that divine goodness is less likely to cause such natures to be instantiated. Second, all natures are ways of participating in God. Perhaps there just are no essentially contradictory ways of participating in God, and so such natures are impossible. (Note that this is compatible with the existence of exceptional circumstances where there are contradictory moral norms.)

Along similar lines, note that the Natural Lawyer has to face the same abhorrent action objection that the Divine Command Theorist does. It seems that the Natural Lawyer has to endorse conditionals like:

• If our nature were to command torture of the innocent, then such torture would be morally required.

But a theistic Natural Lawyer could say (parallel to what typical Divine Command Theorists do) that it is impossible for our nature to command such a thing, either because it would be contrary to God’s goodness to instantiate such a nature or because such a nature is impossible.

I am collecting ways in which Natural Law, and Aristotelian metaphysics in general, requires theism…

Natural Law and the epistemology of permissions

It is hard to know that something is permissible, because an action is permissible provided that no moral consideration is decisive against it. Thus, it seems, to know that an action is permissible requires surveying the infinite set of all possible moral considerations and checking that none of them rules out the action.

But natural law ethics provides a handy shortcut:

1. Actions characteristic of a kind of being are permissible in relevantly normal circumstances.

Principle (1), for instance, makes it difficult to defend strong versions of antinatalism or of ethical vegetarianism by conferring a default permission status on reproduction and the eating of meat, since we are organisms (and hence characteristically reproduce in appropriate circumstances) and omnivores (and hence have a characteristic diet that includes meat).

The natural permission principle shifts the discussion from the question whether a given action type, characteristic of us humans, is generally permissible, to the question whether the circumstances at hand are relevantly normal. Thus, (1) still leaves open the possibility of an antinatalism that holds that things are so abnormally bad that it’s wrong to reproduce, or an ethical vegetarianism on which global conditions require us to forego meat.

Subscribing to principle (1) also explains the incredulous stare I see on students’ faces when I explain Andrea Dworkin’s view that heterosexual intercourse is always wrong.

Conciliationism and natural law epistemology

Suppose we have a group of perfect Bayesian agents with the same evidence who nonetheless disagree. By definition of “perfect Bayesian agent”, the disagreement must be rooted in differences in priors between these peers. Here is a natural-sounding recipe for conciliating their disagreement: the agents go back to their priors, they replace their priors by the arithmetic average of the priors within the group, and then they re-updated on all the evidence that they had previous got. (And in so doing, they lose their status as perfect Bayesian agents, since this procedure is not a Bayesian update.)

Since the average of consistent probability functions is a consistent probability function, we maintain consistency. Moreover, the recipe is a conciliation in the following sense: whenever the agents previously all agreed on some posterior, they still agree on it after the procedure, and with the same credence as before. Whenever the agents disagreed on something, they now agree, and their new credence is strictly between the lowest and highest posteriors that the group assigned prior to conciliation.

Here is a theory that can give a justification for this natural-sounding procedure. Start with natural law Bayesianism which is an Aristotelian theory that holds that human nature sets constraints on what priors count as natural to human beings. Thus, just as it is unnatural for a human being to be ten feet tall, it is unnatural for a human being to have a prior of 10⁻¹⁰⁰ for there being mathematically elegant laws of nature. And just as there is a range of heights that is natural for a mature human being, there is a range of priors that is natural for the proposition that there are mathematically elegant laws.

Aristotelian natures, however, are connected with the actual propensities of the beings that have them. Thus, humans have a propensity to develop a natural height. Because of this propensity, an average height is likely to be a natural height. More generally, for any numerical attribute governed by a nature of kind K, the average value of that attribute amongst the Ks is likely to be within the natural range. Likely, but not certain. It is possible, for instance, to have a species whose average weight is too high or too low. But it’s unlikely.

Consequently, we would expect that if we average the values of the prior for a given proposition q over the human population, the average would be within the natural range for that prior. Moreover, as the size of a group increases, we expect the average value of an attribute over the group to approach the average value the attribute has in the full population. Then, if I am a member of the group of disagreeing evidence-sharing Bayesians, it is more likely that the average of the priors for q amongst the members of the group lies within the natural human range for that prior for q than it is that my own prior for q lies within the natural human range for q. It is more likely that I have an unnatural height or weight than that the average in a larger group is outside the natural range for height or weight.

Thus, the prior-averaging recipe is likely to replace priors that are defectively outside the normal human range with priors within the normal human range. And that’s to the good rationally speaking, because on a natural law epistemology, the rational way for humans to reason is the same as the normal way for humans to reason.

It’s an interesting question how this procedure compares to the procedure of simply averaging the posteriors. Philosophically, there does not seem to be a good justification of the latter. It turns out, however, that typically the two procedures give the same result. For instance, I had my computer randomly generate 100,000 pairs of four-point prior probability spaces, and compare the result of prior- to posterior-averaging. The average of the absolute value of the difference in the outputs was 0.028. So the intuitive, but philosophically unjustified, averaging of posteriors is close to what I think is the more principled averaging of priors.

The procedure also has an obvious generalization from the case where the agents share the same evidence to the case where they do not. What’s needed is for the agents to make a collective list of all their evidence, replace their priors by averaged priors, and then update on all the items in the collective list.