# Necessity, Possibility, and Impossibility

I spoke here about various kinds of necessity, but did not explain the nature of necessity in general. And in the recent post on Hume’s idea of causality, it was not necessary to explain the nature of necessity, because the actual idea of causality does not include necessity. Thus for example a ball can break a window even if it would have been possible for someone to catch the ball, but the person did not do so.

Sometimes it is asked whether necessity implies possibility: if it is necessary that Tuesday follow Monday, it is possible for Tuesday to follow Monday? I am inclined (and I think most are inclined) to say yes, on the grounds that to say that something is not possible is normally understood to imply that the thing is impossible; thus if it is not possible for Tuesday to follow Monday, it is impossible. But this is largely a verbal question: regardless of how we answer this, the real point is that the necessary is the same kind of thing as the possible, except that possibilities are many while the necessary is one. And likewise, a count of zero for the same things implies impossibility. Thus there is something that we are counting: if we find none of them, we speak of an impossibility. If we find only one, we speak of one necessity. And if we find many, we speak of many possibilities.

What are we counting here? Let’s take an example. Horses can be white, or red, or brown, among other possibilities. So there are many possible colors for a horse. And on the other hand snow is always white (or so let us pretend.) So there is only one possible color for snow, and so snow is “necessarily” white. Meanwhile, air is always colorless (or so let us pretend.) So it is impossible for air to have a color. Based on this example, we propose that what we are counting is the number of forms that are suitable for a given matter. Someone might object that if we analyze the word “suitable” here it might involve some sort of circularity. This may well be the case; this is a common occurrence, as with desire and the good, and with virtue and happiness. Nonetheless, I think we will find it worthwhile to work with this definition, just as in those earlier cases.

# Miracles and Anomalies: Or, Your Religion is False

In 2011 there was an apparent observation of neutrinos traveling faster than light. Wikipedia says of this, “Even before the mistake was discovered, the result was considered anomalous because speeds higher than that of light in a vacuum are generally thought to violate special relativity, a cornerstone of the modern understanding of physics for over a century.” In other words, most scientists did not take the result very seriously, even before any specific explanation was found. As I stated here, it is possible to push unreasonably far in this direction, in such a way that one will be reluctant to ever modify one’s current theories. But there is also something reasonable about this attitude.

Alexander Pruss explains why scientists tend to be skeptical of such anomalous results in this post on Bayesianism and anomaly:

One part of the problem of anomaly is this. If a well-established scientific theory seems to predict something contrary to what we observe, we tend to stick to the theory, with barely a change in credence, while being dubious of the auxiliary hypotheses. What, if anything, justifies this procedure?

Here’s my setup. We have a well-established scientific theory T and (conjoined) auxiliary hypotheses A, and T together with A uncontroversially entails the denial of some piece of observational evidence E which we uncontroversially have (“the anomaly”). The auxiliary hypotheses will typically include claims about the experimental setup, the calibration of equipment, the lack of further causal influences, mathematical claims about the derivation of not-E from T and the above, and maybe some final catch-all thesis like the material conditional that if T and all the other auxiliary hypotheses obtain, then E does not obtain.

For simplicity I will suppose that A and T are independent, though of course that simplifying assumption is rarely true.

Here’s a quick and intuitive thought. There is a region of probability space where the conjunction of T and A is false. That area is divided into three sub-regions:

1. T is true and A is false
2. T is false and A is true
3. both are false.

The initial probabilities of the three regions are, respectively, 0.0999, 0.0009999 and 0.0001. We know we are in one of these three regions, and that’s all we now know. Most likely we are in the first one, and the probability that we are in that one given that we are in one of the three is around 0.99. So our credence in T has gone down from three nines (0.999) to two nines (0.99), but it’s still high, so we get to hold on to T.

Still, this answer isn’t optimistic. A move from 0.999 to 0.99 is actually an enormous decrease in confidence.

“This answer isn’t optimistic,” because in the case of the neutrinos, this analysis would imply that scientists should have instantly become ten times more willing to consider the possibility that the theory of special relativity is false. This is surely not what happened.

Pruss therefore presents an alternative calculation:

But there is a much more optimistic thought. Note that the above wasn’t a real Bayesian calculation, just a rough informal intuition. The tip-off is that I said nothing about the conditional probabilities of E on the relevant hypotheses, i.e., the “likelihoods”.

Now setup ensures:

1. P(E|A ∧ T)=0.

What can we say about the other relevant likelihoods? Well, if some auxiliary hypothesis is false, then E is up for grabs. So, conservatively:

1. P(E|∼A ∧ T)=0.5
2. P(E|∼A ∧ ∼T)=0.5

But here is something that I think is really, really interesting. I think that in typical cases where T is a well-established scientific theory and A ∧ T entails the negation of E, the probability P(E|A ∧ ∼T) is still low.

The reason is that all the evidence that we have gathered for T even better confirms the hypothesis that T holds to a high degree of approximation in most cases. Thus, even if T is false, the typical predictions of T, assuming they have conservative error bounds, are likely to still be true. Newtonian physics is false, but even conditionally on its being false we take individual predictions of Newtonian physics to have a high probability. Thus, conservatively:

1. P(E|A ∧ ∼T)=0.1

Very well, let’s put all our assumptions together, including the ones about A and T being independent and the values of P(A) and P(T). Here’s what we get:

1. P(E|T)=P(E|A ∧ T)P(A|T)+P(E|∼A ∧ T)P(∼A|T)=0.05
2. P(E|∼T)=P(E|A ∧ ∼T)P(A|∼T)+P(E|∼A ∧ ∼T)P(∼A|∼T) = 0.14.

Plugging this into Bayes’ theorem, we get P(T|E)=0.997. So our credence has crept down, but only a little: from 0.999 to 0.997. This is much more optimistic (and conservative) than the big move from 0.999 to 0.99 that the intuitive calculation predicted.

So, if I am right, at least one of the reasons why anomalies don’t do much damage to scientific theories is that when the scientific theory T is well-confirmed, the anomaly is not only surprising on the theory, but it is surprising on the denial of the theory—because the background includes the data that makes T “well-confirmed” and would make E surprising even if we knew that T was false.

To make the point without the mathematics (which in any case is only used to illustrate the point, since Pruss is choosing the specific values himself), if you have a theory which would make the anomaly probable, that theory would be strongly supported by the anomaly. But we already know that theories like that are false, because otherwise the anomaly would not be an anomaly. It would be normal and common. Thus all of the actually plausible theories still make the anomaly an improbable observation, and therefore these theories are only weakly supported by the observation of the anomaly. The result is that the new observation makes at most a minor difference to your previous opinion.

We can apply this analysis to the discussion of miracles. David Hume, in his discussion of miracles, seems to desire a conclusive proof against them which is unobtainable, and in this respect he is mistaken. But near the end of his discussion, he brings up the specific topic of religion and says that his argument applies to it in a special way:

Upon the whole, then, it appears, that no testimony for any kind of miracle has ever amounted to a probability, much less to a proof; and that, even supposing it amounted to a proof, it would be opposed by another proof; derived from the very nature of the fact, which it would endeavour to establish. It is experience only, which gives authority to human testimony; and it is the same experience, which assures us of the laws of nature. When, therefore, these two kinds of experience are contrary, we have nothing to do but subtract the one from the other, and embrace an opinion, either on one side or the other, with that assurance which arises from the remainder. But according to the principle here explained, this subtraction, with regard to all popular religions, amounts to an entire annihilation; and therefore we may establish it as a maxim, that no human testimony can have such force as to prove a miracle, and make it a just foundation for any such system of religion.

The idea seems to be something like this: contrary systems of religion put forth miracles in their support, so the supporting evidence for one religion is more or less balanced by the supporting evidence for the other. Likewise, the evidence is weakened even in itself by people’s propensity to lies and delusion in such matters (some of this discussion was quoted in the earlier post on Hume and miracles). But in addition to the fairly balanced evidence we have experience basically supporting the general idea that the miracles do not happen. This is not outweighed by anything in particular, and so it is the only thing that remains after the other evidence balances itself out of the equation. Hume goes on:

I beg the limitations here made may be remarked, when I say, that a miracle can never be proved, so as to be the foundation of a system of religion. For I own, that otherwise, there may possibly be miracles, or violations of the usual course of nature, of such a kind as to admit of proof from human testimony; though, perhaps, it will be impossible to find any such in all the records of history. Thus, suppose, all authors, in all languages, agree, that, from the first of January, 1600, there was a total darkness over the whole earth for eight days: suppose that the tradition of this extraordinary event is still strong and lively among the people: that all travellers, who return from foreign countries, bring us accounts of the same tradition, without the least variation or contradiction: it is evident, that our present philosophers, instead of doubting the fact, ought to receive it as certain, and ought to search for the causes whence it might be derived. The decay, corruption, and dissolution of nature, is an event rendered probable by so many analogies, that any phenomenon, which seems to have a tendency towards that catastrophe, comes within the reach of human testimony, if that testimony be very extensive and uniform.

But suppose, that all the historians who treat of England, should agree, that, on the first of January, 1600, Queen Elizabeth died; that both before and after her death she was seen by her physicians and the whole court, as is usual with persons of her rank; that her successor was acknowledged and proclaimed by the parliament; and that, after being interred a month, she again appeared, resumed the throne, and governed England for three years: I must confess that I should be surprised at the concurrence of so many odd circumstances, but should not have the least inclination to believe so miraculous an event. I should not doubt of her pretended death, and of those other public circumstances that followed it: I should only assert it to have been pretended, and that it neither was, nor possibly could be real. You would in vain object to me the difficulty, and almost impossibility of deceiving the world in an affair of such consequence; the wisdom and solid judgment of that renowned queen; with the little or no advantage which she could reap from so poor an artifice: all this might astonish me; but I would still reply, that the knavery and folly of men are such common phenomena, that I should rather believe the most extraordinary events to arise from their concurrence, than admit of so signal a violation of the laws of nature.

But should this miracle be ascribed to any new system of religion; men, in all ages, have been so much imposed on by ridiculous stories of that kind, that this very circumstance would be a full proof of a cheat, and sufficient, with all men of sense, not only to make them reject the fact, but even reject it without farther examination. Though the Being to whom the miracle is ascribed, be, in this case, Almighty, it does not, upon that account, become a whit more probable; since it is impossible for us to know the attributes or actions of such a Being, otherwise than from the experience which we have of his productions, in the usual course of nature. This still reduces us to past observation, and obliges us to compare the instances of the violation of truth in the testimony of men, with those of the violation of the laws of nature by miracles, in order to judge which of them is most likely and probable. As the violations of truth are more common in the testimony concerning religious miracles, than in that concerning any other matter of fact; this must diminish very much the authority of the former testimony, and make us form a general resolution, never to lend any attention to it, with whatever specious pretence it may be covered.

Notice how “unfair” this seems to religion, so to speak. What is the difference between the eight days of darkness, which Hume would accept, under those conditions, and the resurrection of the queen of England, which he would not? Hume’s reaction to the two situations is more consistent than first appears. Hume would accept the historical accounts about England in the same way that he would accept the accounts about the eight days of darkness. The difference is in how he would explain the accounts. He says of the darkness, “It is evident, that our present philosophers, instead of doubting the fact, ought to receive it as certain, and ought to search for the causes whence it might be derived.” Likewise, he would accept the historical accounts as certain insofar as they say the a burial ceremony took place, the queen was absent from public life, and so on. But he would not accept that the queen was dead and came back to life. Why? The “search for the causes” seems to explain this. It is plausible to Hume that causes of eight days of darkness might be found, but not plausible to him that causes of a resurrection might be found. He hints at this in the words, “The decay, corruption, and dissolution of nature, is an event rendered probable by so many analogies,” while in contrast a resurrection would be “so signal a violation of the laws of nature.”

It is clear that Hume excludes certain miracles, such as resurrection, from the possibility of being established by the evidence of testimony. But he makes the additional point that even if he did not exclude them, he would not find it reasonable to establish a “system of religion” on such testimony, given that “violations of truth are more common in the testimony concerning religious miracles, than in that concerning any other matter of fact.”

It is hard to argue with the claim that “violations of truth” are especially common in testimony about miracles. But does any of this justify Hume’s negative attitude to miracles as establishing “systems of religion,” or is this all just prejudice?  There might well be a good deal of prejudice involved here in his opinions. Nonetheless, Alexander Pruss’s discussion of anomaly allows one to formalize Hume’s idea here as actual insight as well.

One way to look at truth in religion is to look at it as a way of life or as membership in a community. And in this way, asking whether miracles can establish a system of religion is just asking whether a person can be moved to a way of life or to join a community through such things. And clearly this is possible, and often happens. But another way to consider truth in religion is to look at a doctrinal system as a set of claims about how the world is. Looked at in this way, we should look at a doctrinal system as presenting a proposed larger context of our place in the world, one that we would be unaware of without the religion. This implies that one should have a prior probability (namely prior to consideration of arguments in its favor) strongly against the system considered as such, for reasons very much like the reasons we should have a prior probability strongly against Ron Conte’s predictions.

We can thus apply Alexander Pruss’s framework. Let us take Mormonism as the “system of religion” in question. Then taken as a set of claims about the world, our initial probability would be that it is very unlikely that the world is set up this way. Then let us take a purported miracle establishing this system: Joseph Smith finds his golden plates. In principle, if this cashed out in a certain way, it could actually establish his system. But it doesn’t cash out that way. We know very little about the plates, the circumstances of their discovery (if there was any), and their actual content. Instead, what we are left with is an anomaly: something unusual happened, and it might be able to be described as “finding golden plates,” but that’s pretty much all we know.

Then we have the theory, T, which has a high prior probability: Mormonism is almost certainly false. We have the observation : Joseph Smith discovered his golden plates (in one sense or another.) And we have the auxiliary hypotheses which imply that he could not have discovered the plates if Mormonism is false. The Bayesian updates in Pruss’s scheme imply that our conclusion is this: Mormonism is almost certainly false, and there is almost certainly an error in the auxiliary hypotheses that imply he could not have discovered them if it were false.

Thus Hume’s attitude is roughly justified: he should not change his opinion about religious systems in any significant way based on testimony about miracles.

To make you feel better, this does not prove that your religion is false. It just nearly proves that. In particular, this does not take into an account an update based on the fact that “many people accept this set of claims.” This is a different fact, and it is not an anomaly. If you update on this fact and end up with a non-trivial probability that your set of claims is true, testimony about miracles might well strengthen this into conviction.

I will respond to one particular objection, however. Some will take this argument to be stubborn and wicked, because it seems to imply that people shouldn’t be “convinced even if someone rises from the dead.” And this does in fact follow, more or less. An anomalous occurrence in most cases will have a perfectly ordinary explanation in terms of things that are already a part of our ordinary understanding of the world, without having to add some larger context. For example, suppose you heard your fan (as a piece of furniture, not as a person) talking to you. You might suppose that you were hallucinating. But suppose it turns out that you are definitely not hallucinating. Should you conclude that there is some special source from outside the normal world that is communicating with you? No: the fan scenario can happen, and it turns out to have a perfectly everyday explanation. We might agree with Hume that it would be much more implausible that a resurrection would have an everyday explanation. Nonetheless, even if we end up concluding to the existence of some larger context, and that the miracle has no such everyday explanation, there is no good reason for it to be such and such a specific system of doctrine. Consider again Ron Conte’s predictions for the future. Most likely the things that happen between now and 2040, and even the things that happen in the 2400s, are likely to be perfectly ordinary (although the things in the 2400s might differ from current events in fairly radical ways). But even if they are not, and even if apocalyptic, miraculous occurrences are common in those days, this does not raise the probability of Conte’s specific predictions above any trivial level. In the same way, the anomalous occurrences involved in the accounts of miracles will not lend any significant probability to a religious system.

The objection here is that this seems unfair to God, so to speak. What if God wanted to reveal something to the world? What could he do, besides work miracles? I won’t propose a specific answer to this, because I am not God. But I will illustrate the situation with a little story to show that there is nothing unfair to God about it.

Suppose human beings created an artificial intelligence and raised it in a simulated environment. Wanting things to work themselves out “naturally,” so to speak, because it would be less work, and because it would probably be necessary to the learning process, they institute “natural laws” in the simulated world which are followed in an exceptionless way. Once the AI is “grown up”, so to speak, they decide to start communicating with it. In the AI’s world, this will surely show up as some kind of miracle: something will happen that was utterly unpredictable to it, and which is completely inconsistent with the natural laws as it knew them.

Will the AI be forced by the reasoning of this post to ignore the communication? Well, that depends on what exactly occurs and how. At the end of his post, Pruss discusses situations where anomalous occurrences should change your mind:

Note that this argument works less well if the anomalous case is significantly different from the cases that went into the confirmation of T. In such a case, there might be much less reason to think E won’t occur if T is false. And that means that anomalies are more powerful as evidence against a theory the more distant they are from the situations we explored before when we were confirming T. This, I think, matches our intuitions: We would put almost no weight in someone finding an anomaly in the course of an undergraduate physics lab—not just because an undergraduate student is likely doing it (it could be the professor testing the equipment, though), but because this is ground well-gone over, where we expect the theory’s predictions to hold even if the theory is false. But if new observations of the center of our galaxy don’t fit our theory, that is much more compelling—in a regime so different from many of our previous observations, we might well expect that things would be different if our theory were false.

And this helps with the second half of the problem of anomaly: How do we keep from holding on to T too long in the light of contrary evidence, how do we allow anomalies to have a rightful place in undermining theories? The answer is: To undermine a theory effectively, we need anomalies that occur in situations significantly different from those that have already been explored.

If the AI finds itself in an entirely new situation, e.g. rather than hearing an obscure voice from a fan, it is consistently able to talk to the newly discovered occupant of the world on a regular basis, it will have no trouble realizing that its situation has changed, and no difficulty concluding that it is receiving communication from its author. This does, sort of, give one particular method that could be used to communicate a revelation. But there might well be many others.

Our objector will continue. This is still not fair. Now you are saying that God could give a revelation but that if he did, the world would be very different from the actual world. But what if he wanted to give a revelation in the actual world, without it being any different from the way it is? How could he convince you in that case?

Let me respond with an analogy. What if the sky were actually red like the sky of Mars, but looked blue like it is? What would convince you that it was red? The fact that there is no way to convince you that it is red in our actual situation means you are unfairly prejudiced against the redness of the sky.

In other words, indeed, I am unwilling to be convinced that the sky is red except in situations where it is actually red, and those situations are quite different from our actual situation. And indeed, I am unwilling to be convinced of a revelation except in situations where there is actually a revelation, and those are quite different from our actual situation.

# Common Sense and Culture

If we compare what I said about common sense to the letter of St. Augustine on the errors of the Donatists, quoted here, it seems that St. Augustine takes his belief in Christianity to be a matter of accepting common sense:

For they prefer to the testimonies of Holy Writ their own contentions, because, in the case of Cæcilianus, formerly a bishop of the Church of Carthage, against whom they brought charges which they were and are unable to substantiate, they separated themselves from the Catholic Church—that is, from the unity of all nations. Although, even if the charges had been true which were brought by them against Cæcilianus, and could at length be proved to us, yet, though we might pronounce an anathema upon him even in the grave, we are still bound not for the sake of any man to leave the Church, which rests for its foundation on divine witness, and is not the figment of litigious opinions, seeing that it is better to trust in the Lord than to put confidence in man. For we cannot allow that if Cæcilianus had erred,— a supposition which I make without prejudice to his integrity—Christ should therefore have forfeited His inheritance. It is easy for a man to believe of his fellow-men either what is true or what is false; but it marks abandoned impudence to desire to condemn the communion of the whole world on account of charges alleged against a man, of which you cannot establish the truth in the face of the world.

It is true that St. Augustine talks about “divine witness” and so on here, but it is also easy to see that a significant source of his confidence is existing widespread religious agreement. It is foolish to abandon “the unity of all nations,” and impudent to “condemn the communion of the whole world.” And the problem with “charges alleged against a man, of which you cannot establish the truth in the face of the world,” is that if you disagree with the common consent of mankind, you should first attempt to convince others before putting forward your personal ideas as absolute truth.

Is common sense a real reason for St. Augustine’s religious position, or he is merely attempting to justify himself? Consider his famous rebuke of those who attack science in the name of religion:

Usually, even a non-Christian knows something about the earth, the heavens, and the other elements of this world, about the motion and orbit of the stars and even their size and relative positions, about the predictable eclipses of the sun and moon, the cycles of the years and the seasons, about the kinds of animals, shrubs, stones, and so forth, and this knowledge he holds to as being certain from reason and experience. Now, it is a disgraceful and dangerous thing for an infidel to hear a Christian, presumably giving the meaning of Holy Scripture, talking non-sense on these topics; and we should take all means to prevent such an embarrassing situation, in which people show up vast ignorance in a Christian and laugh it to scorn. The shame is not so much that an ignorant individual is derided, but that people outside the household of the faith think our sacred writers held such opinions, and, to the great loss of those for whose salvation we toil, the writers of our Scripture are criticized and rejected as unlearned men. If they find a Christian mistaken in a field which they themselves know well and hear him maintaining his foolish opinions about our books, how are they going to believe those books in matters concerning the resurrection of the dead, the hope of eternal life, and the kingdom of heaven, when they think their pages are full of falsehoods on facts which they themselves have learnt from experience and the light of reason? Reckless and incompetent expounders of holy Scripture bring untold trouble and sorrow on their wiser brethren when they are caught in one of their mischievous false opinions and are taken to task by those who are not bound by the authority of our sacred books. For then, to defend their utterly foolish and obviously untrue statements, they will try to call upon Holy Scripture for proof and even recite from memory many passages which they think support their position, although “they understand neither what they say nor the things about which they make assertion.”

St. Augustine in fact seems to be giving priority to common sense over religion here. If your religion contradicts common sense, your religion is wrong and common sense is right. This suggests that his argument for his religion from common sense is an honest one; it might even be his strongest reason for his belief.

As I said in the earlier post, the argument for religion from the consent of humanity had problems even at the time, and as things stand, it has no real relevance. There is no religious doctrine, let alone any religion, that one could reasonably say is accepted by even a majority of humanity, let alone by all. At any rate, this is the case unless one makes one’s doctrine far vaguer than would be permitted by any religion.

I concluded above that St. Augustine’s defense of common sense is likely an honest one. But note that this was not necessary: it would be perfectly possible for someone to defend common sense in order to justify themselves, without actually caring about the truth of common sense. In fact, consider what I said here about Scott Sumner and James Larson. Larson’s claim to accept realism is basically not an honest one. I do not mean that he does not believe it, but that its truth is irrelevant to him. What matters to him is that he can seemingly justify himself in maintaining his religious position in the face of all opposition.

Consider the cynical position of Francis Bacon about people relative to truth, discussed here. According to Bacon, no one is interested in truth in itself, but only as a means to other things. While the cynical position overall is incorrect, there is a lot of truth in it. Consequently, it will not be uncommon for someone to defend common sense, not so much because of its truth, but as part of a larger project of defending their culture. Culture is bound up with claims about the world, and defending culture therefore involves defending claims about the world. And if everyone accepts something, presumably everyone in your culture accepts it. One sign of this, of course, would be if someone passes freely back and forth between putting forth things that everyone accepts, and things that everyone in their culture accepts, as though these were equivalent.

Likewise, someone can attack common sense, not for the purpose of truth, but in order to engage in a kind of culture war. Consider the recent comments by “werzekeugjj” on the last post. There is no option here but to explain these comments with the methods of Ezekiel Bulver. For they cannot possibly represent opinions about the world at all, let alone opinions that were arrived at by honest means. Werzekeugjj, for example, responds to the question, “Do people sometimes write comments?” with “No.” As I pointed out there, if they do not, then he did not compose those comments, and there is nothing to reply to. As Aristotle puts it,

We can, however, demonstrate negatively even that this view is impossible, if our opponent will only say something; and if he says nothing, it is absurd to seek to give an account of our views to one who cannot give an account of anything, in so far as he cannot do so. For such a man, as such, is from the start no better than a vegetable.

Nor is it possible to apply a principle of charity here and say that Werzekeugjj intends to say that their claims are true in some complicated metaphysical sense. This does apply to the position of the blogger from Atheism and the City, discussed in that post. He presumably does not intend to reject common sense. I simply point out in my response that common sense is enough to draw the conclusions about causality that matter. The point is that this cannot apply to Werzekeugjj’s expressed position, because I spoke expressly of things in the everyday way, and the response was that the everyday claims themselves are false.

Of course, no one actually thinks that the everyday claims are false, including Werzekeugjj. What was the purpose of composing these comments, then?

We can gather a clue from this comment:

“in such a block unniverse there is no time flow
so your point on finalism or causality is moot
same with God
they don’t exist

The body of the post does not mention God, and God is not the topic. Why then does Werzekeugjj bring up God here? The most likely motivation is the kind of culture war motivation discussed here. Werzekeugjj associated talk of causality and reasons with talk of God, and intends to attack a culture that speaks this way with whatever it takes, including a full on rejection of common sense. Science has shown that your common sense views of the world are entirely false, Werzekeugjj says, and therefore you might as well abandon the rest of your culture (including its talk of God) along with the rest of your views.

Supposedly describing their intentions, Werzekeugjj says,

i’m not trying to understand the world or to change your mind but i’m trying to state what is true
and i’m puzzled by how you think there is no problem with arguments like these

This is false, precisely as a description of their personal motives. No one who says that balls never break windows and that they did not write their comments (in the very comments themselves) can pretend to be “trying to state what is true.” Sorry, but that is not your intention. More reasonably, we can suppose that Werzekeugjj sees my post as part of a project of defending a certain culture, and they intend to attack that culture.

But that is an inaccurate understanding of the post. I defend common sense because it is right, not because it is a part of any particular culture. As Bryan Caplan puts it, “Common sense is the foundation of all reasoning.  If you want to reject a common-sense claim, you’d better do it in the name of an even stronger common-sense claim.”

# Explaining Causality

a) Per Hume and his defenders, we can’t really observe causation. All we can see is event A in spacetime, then event B in spacetime. We have no reason to posit that event A and event B are, say, chairs or dogs; we can stick with a sea of observed events, and claim that the world is “nothing more” but a huge set of random 4D events. While I can see that giving such an account restores formal causation, it doesn’t salvage efficient causation, and doesn’t even help final causation. How could you move there from our “normal” view?

b) You mention that the opinion “laws are observed patterns” is not a dominant view; though, even though I’d like to sit with the majority, I can’t go further than a). I can’t build an argument for this, and fail to see how Aristotle put his four causes correctly. I always end up gnawing on an objection, like “causation is only in the mind” or similar. Help?

It is not my view that the world is a huge set of random 4D events. This is perhaps the view of Atheism and the City, but it is a mistaken one. The blogger is not mistaken in thinking that there are problems with presentism, but they cannot be solved by adopting an eternalist view. Rather, these two positions constitute a Kantian dichotomy, and as usual, both positions are false. For now, however, I will leave this to the consideration of the reader. It is not necessary to establish this to respond to the questions above.

Consider the idea that “we can’t really observe causation.” As I noted here, it does not make sense to say that we cannot observe causation unless we already understand what causation is. If the word were meaningless to us, we would have no argument that we don’t observe it; it is only because we do understand the idea of causation that we can even suggest that it might be difficult to observe. And if we do have the idea, we got the idea from somewhere, and that could only have been… from observation, of course, since we don’t have anything else to get ideas from.

Let us untie the knot. I explained causality in general in this way:

“Cause” and “effect” simply signify that the cause is the origin of the effect, and that the effect is from the cause, together with the idea that when we understand the cause, we understand the explanation for the effect. Thus “cause” adds to “origin” a certain relationship with the understanding; this is why Aristotle says that we do not think we understand a thing until we know its cause, or “why” it is. We do not understand a thing until we know its explanation.

Note that there is something “in the mind” about causality. Saying to oneself, “Aha! So that’s why that happened!” is a mental event. And we can also see how it is possible to observe causality: we can observe that one thing is from another, i.e. that a ball breaks a window, and we can also observe that knowing this provides us a somewhat satisfactory answer to the question, “Why is the window broken?”, namely, “Because it was hit by a ball.”

Someone (e.g. Atheism and the City) might object that we also cannot observe one thing coming from another. We just observe the two things, and they are, as Hume says, “loose and separate.” Once again, however, we would have no idea of “from” unless we got it from observing things. In the same early post quoted above, I explained the idea of origin, i.e. that one thing is from another:

Something first is said to be the beginning, principle, or origin of the second, and the second is said to be from the first. This simply signifies the relationship already described in the last post, together with an emphasis on the fact that the first comes before the second by “consequence of being”, in the way described.

“The relationship already described in the last post” is that of before and after. In other words, wherever we have any kind of order at all, we have one thing from another. And we observe order, even when we simply see one thing after another, and thus we also observe things coming from other things.

What about efficient causality? If we adopt the explanation above, asserting the existence of efficient causality is nothing more or less than asserting that things sometimes make other things happen, like balls breaking windows, and that knowing about this is a way for us to understand the effects (e.g. broken windows.)

Similarly, denying the existence of efficient causality means either denying that anything ever makes anything else happen, or denying that knowing about this makes us understand anything, even in a minor way. Atheism and the City seems to want to deny that anything ever makes anything else happen:

Most importantly, my view technically is not that causality doesn’t exist, it’s that causality doesn’t exist in the way we typically think it does. That is, my view of causality is completely different from the general every day notion of causality most people have. The naive assumption one often gets when hearing my view is that I’m saying cause and effect relationships don’t exist at all, such that if you threw a brick at glass window it wouldn’t shatter, or if you jumped in front of a speeding train you wouldn’t get smashed to death by it. That’s not what my view says at all.

On my view of causality, if you threw a brick at a glass window it would shatter, if you jumped in front of a speeding train you’d be smashed to death by it. The difference between my view of causality vs the typical view is that on my view causes do not bring their effects into existence in the sense of true ontological becoming.

I am going to leave aside the discussion of “true ontological becoming,” because it is a distraction from the real issue. Does Atheism and the City deny that things ever make other things happen? It appears so, but consider that “things sometimes make other things happen” is just a more general description of the very same situations as descriptions like, “Balls sometimes break windows.” So if you want to deny that things make other things happen, you should also deny that balls break windows. Now our blogger perhaps wants to say, “I don’t deny that balls break windows in the everyday sense, but they don’t break them in a true ontological sense.” Again, I will simply point in the right direction here. Asserting the existence of efficient causes does not describe a supposedly “truly true” ontology; it is simply a more general description of a situation where balls sometimes break windows.

We can make a useful comparison here between understanding causality, and understanding desire and the good. The knowledge of desire begins with a fairly direct experience, that of feeling the desire, often even as physical sensation. In the same way, we have a direct experience of “understanding something,” namely the feeling of going, “Ah, got it! That’s why this is, this is how it is.” And just as we explain the fact of our desire by saying that the good is responsible for it, we explain the fact of our understanding by saying that the apprehension of causes is responsible. And just as being and good are convertible, so that goodness is not some extra “ontological” thing, so also cause and origin are convertible. But something has to have a certain relationship with us to be good for us; eating food is good for us while eating rocks is not. In a similar way, origins need to have a specific relationship with us in order to provide an understanding of causality, as I said in the post where these questions came up.

Does this mean that “causation is only in the mind”? Not really, any more than the analogous account implies that goodness is only in the mind. An aspect of goodness is in the mind, namely insofar as we distinguish it from being in general, but the thing itself is real, namely the very being of things. And likewise an aspect of causality is in the mind, namely the fact that it explains something to us, but the thing itself is real, namely the relationships of origin in things.

# Common Sense

I have tended to emphasize common sense as a basic source in attempting to philosophize or otherwise understand reality. Let me explain what I mean by the idea of common sense.

The basic idea is that something is common sense when everyone agrees that something is true. If we start with this vague account, something will be more definitively common sense to the degree that it is truer that everyone agrees, and likewise to the degree that it is truer that everyone agrees.

If we consider anything that one might think of as a philosophical view, we will find at least a few people who disagree, at least verbally, with the claim. But we may be able to find some that virtually everyone agrees with. These pertain more to common sense than things that fewer people agree with. Likewise, if we consider everyday claims rather than philosophical ones, we will probably be able to find things that everyone agrees with apart from some very localized contexts. These pertain even more to common sense. Likewise, if everyone has always agreed with something both in the past and present, that pertains more to common sense than something that everyone agrees with in the present, but where some have disagreed in the past.

It will be truer that everyone agrees in various ways: if everyone is very certain of something, that pertains more to common sense than something people are less certain about. If some people express disagreement with a view, but everyone’s revealed preferences or beliefs indicate agreement, that can be said to pertain to common sense to some degree, but not so much as where verbal affirmations and revealed preferences and beliefs are aligned.

Naturally, all of this is a question of vague boundaries: opinions are more or less a matter of common sense. We cannot sort them into two clear categories of “common sense” and “not common sense.” Nonetheless, we would want to base our arguments, as much as possible, on things that are more squarely matters of common sense.

One might object that the proposal is impossible. For no one can really reason except from their own opinions. Otherwise, one might be formulating a chain of argument, but it is not one’s own argument or one’s own conclusion. But this objection is easily answered. In the first place, if everyone agrees on something, you probably agree yourself, and so reasoning from common sense will still be reasoning from your own opinions. Second, if you don’t personally agree, since belief is voluntary, you are capable of agreeing if you choose, and you probably should, for reasons which will be explained in answering the second question.

Nonetheless, the objection is a reasonable place to point out one additional qualification. “Everyone agrees with this” is itself a personal point of view that someone holds, and no one is infallible even with respect to this. So you might think that everyone agrees, while in fact they do not. But this simply means that you have no choice but to do the best you can in determining what is or what is not common sense. Of course you can be mistaken about this, as you can about anything.

Why argue from common sense? I will make two points, a practical one and a theoretical one. The practical point is that if your arguments are public, as for example this blog, rather than written down in a private journal, then you presumably want people to read them and to gain from them in some way. The more you begin from common sense, the more profitable your thoughts will be in this respect. More people will be able to gain from your thoughts and arguments if more people agree with the starting points.

There is also a theoretical point. Consider the statement, “The truth of a statement never makes a person more likely to utter it.” If this statement were true, no one could ever utter it on account of its truth, but only for other reasons. So it is not something that a seeker of truth would ever say. On the other hand, there can be no doubt that the falsehood of some statements, on some occasions, makes those statements more likely to be affirmed by some people. Nonetheless, the nature of language demands that people have an overall tendency, most of the time and in most situations, to speak the truth. We would not be able to learn the meaning of a word without it being applied accurately, most of the time, to the thing that it means. In fact, if everyone was always uttering falsehoods, we would simply learn that “is” means “is not,” and that “is not,” means “is,” and the supposed falsehoods would not be false in the language that we would acquire.

It follows that greater agreement that something is true, other things being equal, implies that the thing is more likely to be actually true. Stones have a tendency to fall down: so if we find a great collection of stones, the collection is more likely to be down at the bottom of a cliff rather than perched precisely on the tip of a mountain. Likewise, people have a tendency to utter the truth, so a great collection of agreement suggests something true rather than something false.

Of course, this argument depends on “other things being equal,” which is not always the case. It is possible that most people agree on something, but you are reasonably convinced that they are mistaken, for other reasons. But if this is the case, your arguments should depend on things that they would agree with even more strongly than they agree with the opposite of your conclusion. In other words, it should be based on things which pertain even more to common sense. Suppose it does not: ultimately the very starting point of your argument is something that everyone else agrees is false. This will probably be an evident insanity from the beginning, but let us suppose that you find it reasonable. In this case, Robin Hanson’s result discussed here implies that you must be convinced that you were created in very special circumstances which would guarantee that you would be right, even though no one else was created in these circumstances. There is of course no basis for such a conviction. And our ability to modify our priors, discussed there, implies that the reasonable behavior is to choose to agree with the priors of common sense, if we find our natural priors departing from them, except in cases where the disagreement is caused by agreement with even stronger priors of common sense. Thus for example in this post I gave reasons for disagreeing with our natural prior on the question, “Is this person lying or otherwise deceived?” in some cases. But this was based on mathematical arguments that are even more convincing than that natural prior.

# Necessary Connection

In Chapter 7 of his Enquiry Concerning Human Understanding, David Hume says about the idea of “necessary connection”:

We have looked at every possible source for an idea of power or necessary connection, and have found nothing. However hard we look at an isolated physical episode, it seems, we can never discover discover anything but one event following another; we never find any force or power by which the cause operates, or any connection between it and its supposed effect. The same holds for the influence of mind on body: the mind wills, and then the body moves, and we observe both events; but we don’t observe– and can’t even conceive– the tie that binds the volition to the motion, i.e. the energy by which the mind causes the body to move. And the power of the will over its own faculties and ideas– i.e. over the mind, as distinct from the body– is no more comprehensible. Summing up, then: throughout the whole of nature there seems not to be a single instance of connection that is conceivable by us. All events seem to be entirely loose and separate. One event follows another, but we never can observe any tie between them. They seem associated, but never connected. And as we can have no idea of anything that never appeared as an impression to our outward sense or inward feeling, we are forced to conclude that we have no idea of ‘connection’ or ‘power’ at all, and that those words– as used in philosophical reasonings or in common life– have absolutely no meaning.

This is not Hume’s final word on the matter, as we will see below, so this has to be taken with a grain of salt, even as a representation of his opinion. Nonetheless, consider this caricature of what he just said:

We have looked at every possible source for an idea of mduvvqi or pdnfhvdkdddd, and have found nothing. However hard we look at an isolated physical episode, it seems, we can never discover anything but events that can be described by perfectly ordinary words; we never find any mduvvqi involved, nor any pdnfhvkdddd.

We could take this to be making the point that “mduvvqi” and “pdnfhvdkdddd” are not words. Other than that, however, the paragraph itself is meaningless, precisely because those “words” are meaningless. It certainly does not make any deep (or shallow for that matter) metaphysical or physical point, nor any special point about the human mind. But Hume’s text is different, and the difference in question is a warning sign of Kantian confusion. If those words had “absolutely no meaning,” in fact, there would be no difference between Hume’s passage and our caricature. Those words are not meaningless, but meaningful, and Hume is even analyzing their meaning in order to supposedly determine that the words are meaningless.

Hume’s analysis in fact proceeds more or less in the following way. We know what it means to say that something is necessary, and it is not the same as saying that the thing always happens. Every human being we have ever seen was less than 20 feet tall. But is it necessary that human beings be less than 20 feet tall? This is a different question, and while we can easily experience someone’s being less than 20 feet tall, it is very difficult to see how we could possibly experience the necessity of this fact, if it is necessary. Hume concludes: we cannot possibly experience the necessity of it. Therefore we can have no idea of such necessity.

But Hume has just contradicted himself: it was precisely by understanding the concept of necessity that he was able to see the difficulty in the idea of experiencing necessity.

Nonetheless, as I said, this is not his final conclusion. A little later he gives a more nuanced account:

The source of this idea of a necessary connection among events seems to be a number of similar instances of the regular pairing of events of these two kinds; and the idea cannot be prompted by any one of these instances on its own, however comprehensively we examine it. But what can a number of instances contain that is different from any single instance that is supposed to be exactly like them? Only that when the mind experiences many similar instances, it acquires a habit of expectation: the repetition of the pattern affects it in such a way that when it observes an event of one of the two kinds it expects an event of the other kind to follow. So the feeling or impression from which we derive our idea of power or necessary connection is a feeling of connection in the mind– a feeling that accompanies the imagination’s habitual move from observing one event to expecting another of the kind that usually follows it. That’s all there is to it. Study the topic from all angles; you will never find any other origin for that idea.

Before we say more, we should concede that this is far more sensible than the claim that the idea of necessity “has absolutely no meaning.” Hume is now conceding that it does have meaning, but claiming that the meaning is about us, not about the thing. When we see someone knock a glass off a table, we perhaps feel a certainty that it will fall and hit the floor. Experiencing that feeling of certainty, he says, is the source of the idea of “necessity.” This is not an unreasonable hypothesis.

However, Hume is also implicitly making a metaphysical argument here which is somewhat less sensible. Our feelings of certainty and uncertainty are subjective qualities of our minds, he suggests, not objective features of the things. Therefore necessity as an objective feature does not and cannot exist. This is not unrelated to his mistaken claim that we cannot know that the future will be similar to the past, even with probability.

What is the correct account here? In fact we already know, from the beginning of the conversation, that “necessary” and “possible” are meaningful words. We also know that in fact we use them to describe objective features of the world. But which features? Attempting to answer this question is where Hume’s approach is pretty sensible. Hume is not mistaken that all of our knowledge is from experience, and ultimately from the senses. He seems to identify experience with sense experience too simplistically, but he is not mistaken that all experience is at least somewhat similar to sense experience; feeling sure that two and two make four is not utterly unlike seeing something red. We want to say that there is something in common there, “something it is like,” to experience one or the other. But if this is the case, it would be reasonable to extend what we said about the senses to intellectual experiences. “The way red looks” cannot, as such, be an objective feature of a thing, but a thing can be objectively red, in such a way that “being red,” together with the nature of the senses, explains why a thing looks red. In a similar way, certainty and uncertainty, insofar as they are ways we experience the world, cannot be objective features of the world as such. Nonetheless, something can be objectively necessary or uncertain, in such a way that “being necessary” or otherwise, together with the nature of our minds, explains why it seems certain or uncertain to us.

There will be a similarity, however. The true nature of red might be quite strange in comparison to the experience of seeing red, as for example it might consist of surface reflectance properties. In a similar way, the true nature of necessity, once it is explained, might be quite strange to us compared to the experience of being certain or uncertain. But that it can be explained is quite certain itself, since the opposite claim would fall into Hume’s original absurdity. There are no hidden essences.

# Truth and Expectation III

Consider what I said at the end of the last post on this topic. When our Mormon protagonist insists that his religion is true, he improves the accuracy of his expectations about the world. His expectations would actually be less accurate he decided that his religious beliefs are false.

Now we said in the first post on truth and expectation that in part we seem to determine the meaning of a statement by the expectations that it implies. If this is the case, then why should we not say that the Mormon’s beliefs are definitely true? In fact, in the post linked above about truth in religion, I suggested that people frequently do mean something like this when they say that their own religion is true. Nonetheless, it is easy to see that truth in this particular sense does not imply that each and every claim in the religion, understood as a claim about the world, is true.

But why not, if one’s expectations become more accurate, just as with statements that are clearly true? As I noted in the earlier post, to say that “that man is pretty tall” is a statement about the man. It is not a statement about myself, nor about my expectations, even if the meaning is partly determined by these things. So ultimately the truth or falsehood of the claim about the man is going to be determined by facts about the man, even if they need to be understood as facts about the man in relation to me and my expectations.

Consider again Scott Sumner’s anti-realism. Scott claims that we cannot distinguish between “our perception of reality, and actual reality.” As I said there, this is right in the sense that we cannot consistently hold the opinion, “This is my opinion about reality, but my opinion is false: reality is actually different.” But we can recognize the distinct meanings in “my perception of reality” and “actual reality.” Scott’s failure to recognize this distinction leads him to suggest on occasion that our beliefs about certain matters are just beliefs about what people in the future will believe. For example, he says in this comment:

You misunderstood Rorty. He is not recommending that you try to trick you colleagues into believing something that is not true. Rather he is merely describing what society regards as true. And who can deny that society tends to regard things as true, when they believe them to be true. No you might say “but what society believes to be true is not always really true.” But Rorty would say that statement means nothing, or else it means that you predict that a future society will have a different view of what is true.

Most people, without even realizing it, assume that there is some sort of “God-like” view of what is “really true” which is separate from what we believe is true, and or will believe in the future to be true. Rorty is an atheist. He believes that what society’s experts believe is the best we can do, the closest we can come to describing reality. Rorty would suggest to Hayek “if you want to convince other economists, use persuasive arguments.” I think that is very reasonable advice. It is what I try to do on this blog.

This is much like Bob Seidensticker’s claim that moral beliefs are beliefs about what society in the future will believe to be moral. In both cases, there is an unacceptable circularity. If our belief is about what people in the future will believe, what are the future people’s beliefs about? There is only one credible explanation here: people’s beliefs are about what they say their beliefs are about, namely the very things they are talking about. Moral beliefs are about whether actions are good or bad, and beliefs describing the world are about the world, not about the people who hold the beliefs, present or future.

This does not imply that there is “some sort of ‘God-like’ view of what is ‘really true’.” It just implies that our beliefs are distinct from other things in the world. Sumner is suggesting that a situation where everyone permanently holds a false belief, forever, is inconceivable. But this is quite conceivable, and we can easily see how it could happen. Just now I counted the cups in my cupboard and there are exactly 14 (if anyone is surprised by that value, most of those are plastic.) It is entirely conceivable, however, that I miscounted. And since I also have some cups that are not currently in the cupboard, if I did, I will probably never get it right, since I will just assume there was some other assortment. And since there is presumably no way for the public to discover the truth about this, society will be permanently deluded about the number of cups in my cupboard at 11:16 AM on July 14, 2018.

What would it mean, then, if it was not “actually true” that there were 14 cups in my cupboard? It would be determined by facts about the cups and the cupboard, not by facts about me, about society, about my expectations or society’s expectations. It would not be actually true if there were, in fact, only 13 cups there, even if no one would ever know this.

This all remains related to expectations, however. I don’t think I miscounted, so I think that if I go again and count them, I will get 14 again. If I did miscount, there is a good chance that counting again would result in a different number. Now I don’t intend to bother, so this expectation is counterfactual. Nonetheless, there are at least conceivable counterfactual situations where I would discover that I was mistaken. In a similar way, to say that the Mormon holds false religious beliefs implies that there are at least counterfactual situations where the falsehood would be uncovered by a violation of his expectations: e.g. if he had been alive at the time and had followed Joseph Smith around all the time to see whether there were any golden plates and so on.

Nonetheless, one cannot ultimately separate the truth of a statement from facts about the thing the statement is about. A statement is true if things are the way it says they are, “the way” being correctly understood here. If this were not the case, the statement would not be about the things in the first place.