I think a lot of that is the Vatican being really really cautious. They’re ultra-cautious about just about everything they say (largely, I think, because they are well aware that (a) a lot of people will take what they say as gospel truth and (b) they don’t get to take anything back, or hardly ever, so if they endorse evolution in some form and then a few decades later a scientist comes back and presents some improvement on the theory that contradicts that form then they will look silly).
So, yeah. What I’m reading into that is that they’re not saying it’s definitely true (in the same way as they do say it’s definitely true that God exists) but they are saying it looks like it just might be.
As well as being ultra-cautious about evolution, Humani Generis says these things (emphasis mine):
divine revelation must be considered morally necessary so that those religious and moral truths which are not of their nature beyond the reach of reason in the present condition of the human race, may be known by all men readily with a firm certainty and with freedom from all error.
the many wonderful external signs God has given, which are sufficient to prove with certitude by the natural light of reason alone the divine origin of the Christian religion
(as well as many other things that don’t appear to me at all ultra-cautious, but where the language is less clear-cut). So this isn’t the result of any general policy of ultra-caution. They are being extra-ultra-cautious about evolution specifically. That was in 1950, and they are less cautious now, but still very cautious. This is why I say their position is notably different from that of naturalistic evolutionary biologists.
… Oh, wait. Have I misunderstood you? If so, we may be arguing at cross-purposes. Here’s our exchange from upthread:
there’s no fundamental reason why a theist couldn’t hold pretty much the exact same view of evolution as an atheist.
Not only is there no fundamental reason, but that’s also pretty much the official position of the Vatican, who are about as theist as you get...
When you said “that”, did you mean (1) “the exact same view of evolution as an atheist” or (2) “the idea that there’s no fundamental reason why a theist couldn’t, etc.”? I’ve been assuming #1 but maybe you meant #2, in which case our disagreement is less sharp than I thought. On #2, my impression is that the Vatican hasn’t said or implied much about what theists as such can reasonably believe about evolution; they’re concerned, rather, with what faithful Catholics can reasonably believe about evolution; and what they’ve said about the latter is, inter alia, that faithful Catholics mustn’t regard it as definitely right (a position that I don’t think is negated by JP2′s statement before the Pontifical Academy of Sciences), and from the things they are willing to call definitely right I don’t think it’s tenable to take this as meaning only that one shouldn’t literally take Pr(evolution)=1. So I don’t think the Vatican thinks it acceptable for Catholics to think about evolution in the same way as most atheists do. Again, what they think about theists more broadly is hard to tell.
From the same document (of the International Theological Commission) that I quoted earlier:
“Since it has been demonstrated that all living organisms on earth are genetically related, it is virtually certain that all living organisms have descended from this first organism.” Given Ratzinger’s approval of that document I don’t think you can reasonably say that a Catholic who thinks that evolution is definitely right (in the ordinary sense of thinking that something is definitely right) is not a faithful Catholic.
Well … the very next sentence of that document is this:
Converging evidence from many studies in the physical and biological sciences furnishes mounting support for some theory of evolution to account for the development and diversification of life on earth, while controversy continues over the pace and mechanisms of evolution.
and while that’s pretty positive about evolution it seems not to be saying that evolution is definitely right. I think what’s going on here is that the authors of that document are happy being very confident about common descent but not so happy being equally confident about evolution.
As to just what sort of evolution, here’s an extract from further on in that document:
It follows that the message of Pope John Paul II cannot be read as a blanket approbation of all theories of evolution, including those of a neo-Darwinian provenance which explicitly deny to divine providence any truly causal role in the development of life in the universe.
As the section of that document that you quoted before makes clear, giving God a “truly causal role” doesn’t necessarily mean endorsing divine intervention. Section 68 -- the one before the one you quoted before—suggests what alternatives the authors had in mind, most notably the idea that he designed the universe in such a way that its natural operation would produce particular results.
This, again, is quite far from any view of evolution that would be endorsed by naturalists.
Even in section 68, I don’t see them saying that God necessarily “designed the universe in such a way that its natural operation would produce particular results,” in any sense stronger than the one which would be absolutely necessary for someone who believes that God is omnipotent and omniscient and the cause of everything that happens. In other words, given that you believe such things about God, then if you see a rock fall and land on the ground, you must believe that God wanted it on the ground. But that wouldn’t necessarily imply that it would have bothered God if it landed in the water instead.
Obviously naturalists would not accept God’s design even in this sense. But it is not a scientific theory one way or another and makes no differences in what you expect to find in nature. So that would still allow for someone to say that naturalistic evolution is definitely true with respect to every prediction that it makes.
Also, I agree that in practice, at least in other places, there is the implication that the world was designed (at least by initial conditions) for the sake of some results rather than others. This comes up especially in regard to marriage and sexuality. However, I don’t see that proposed in any dogmatic way, and it seems to be wishful thinking: if it is objectively by chance that reproduction works the specific way it does, then it becomes harder or impossible to justify Catholic sexual morality. For example, if human beings had developed by evolution in such a way that sexual reproduction required one partner killing the other, it would be obviously justified for them to make technological changes in the way they reproduce.
[...] in any sense stronger than the one which would be absolutely necessary [...]
I’m not sure what sense you have in mind. It seems to me that taking seriously the idea that God is omniscient and the cause of everything that happens more or less commits one to seeing everything as designed by God to achieve whatever his purposes might be.
It is fairly common to say: no, despite having that power God conferred free will upon some of his creatures, so that what they do is not chosen by him. I’m not sure that actually makes sense when looked at clearly, but in any case it seems hard to apply this idea to the laws of nature.
In any case, the document we’re discussing seems to me to be saying that God may guide natural processes like evolution by being a “cause of causes”, and setting up the web of natural causation so as to achieve his ends.
(I don’t mean to imply that it’s saying he did so in such a way as to predetermine everything that happens, by the way; one can imagine God setting up a world that operates at random, and optimizing for a particular probability distribution or something of the kind.)
I’m not sure if we’re disagreeing about anything. I’m not saying that any Church authority has said that “the process of evolution looks exactly like a naturalistic process”, but that what they do say is consistent with this being true. Even assuming God had some motive for setting up things the way they are, how would that imply something in the process of evolution that doesn’t look naturalistic?
I certainly agree that if you say God is relevant at all, that is not something that naturalism would say. But it also doesn’t seem to mean anything concrete about the process.
in so far as the RCC has a position on the actual facts of biological evolution (as opposed to a position on what the Catholic faithful are supposed to think about them):
it seems to me fairly clearly distinguishable from any position a typical atheist evolutionist would adopt, even as regards observable questions like how likely it is that clear evidence of non-natural processes in evolution will ever turn up, though it’s hard to be certain because the official documents carefully avoid being too definite on such matters, and
I bet the senior RC clergy responsible for these documents hold positions more clearly distinguishable from those of typical atheist evolutionists, even as regards etc.; but
I suspect many of them have at least a suspicion that the scientific evidence for naturalist-looking evolution is only ever going to get better, and that clear signs of any kind of divine design in natural organisms are never going to show up.
as regards the RCC’s position on what the Catholic faithful are supposed to think:
I don’t think they are forbidden to adopt positions that, as regards etc., are indistinguishable from those of a typical atheist evolutionist, but
those official documents seem intended to discourage them from holding such positions, and
such positions seem permitted only (I insist on saying!) grudgingly. In particular:
until recently the Catholic faithful were explicitly forbidden to adopt such positions (on account of, e.g., what Humani Generis says about not regarding evolution as definitely correct), and
I strongly suspect that if even a modest amount of credible scientific evidence pointing in the direction of “intelligent design” were to show up, the RCC would return to that sort of stance.
(Not all of those things are directly related to the questions we were discussing.) Does that help?
Ok. I think I agree at least mostly with this summary, although I might qualify a few points.
In itself it’s likely that someone who believes in God will estimate a higher probability of evidence of non-natural processes in evolution than for an atheist. But there is also the third point you mention, namely that even theists may notice that there is currently no such evidence and may suspect that there never will be any. So this might mitigate the difference in their expectations somewhat.
Regarding what is grudgingly permitted or what is encouraged, I think this is less about probability assignments about the facts at issue, and more about the probability that a belief will tend to keep people in the Church or to lead to them leaving the Church. I think this is true even when the Church authorities are explicitly aware that a belief is probably false, at least in some cases. They still will not discourage that belief if it makes it more likely for someone to stay in the Church, unless there is some other motive for discouraging it (e.g. if the belief is very obviously ridiculous, they may discourage it because it could make the Church look bad.)
As well as being ultra-cautious about evolution, Humani Generis says these things (emphasis mine):
Yes; there are some things that the Vatican is extremely certain of (e.g. the divine origin of the Christian religion). Their ultra-caution extends to everything else—a rather large category which just so happens to include evolution.
That was in 1950, and they are less cautious now,
I don’t think they’re less cautious, I just think they recognise that there’s more evidence. At the very least, the fact that no-ones convincingly refuted it in the last sixty-odd years despite all the attention being paid to it counts for quite a bit.
When you said “that”, did you mean (1) “the exact same view of evolution as an atheist” or (2) “the idea that there’s no fundamental reason why a theist couldn’t, etc.”?
I meant that there’s no reason why a theist can’t hold a view of evolution that makes exactly the same predictions in all circumstances as an atheist does. Naturally, the theist’s view will incorporate God as having (at the very least) set up the natural laws that permit it, while the atheist will presumably have those laws simply existing with no particular cause; but they can both agree on what those laws are.
what they’ve said about the latter is, inter alia, that faithful Catholics mustn’t regard it as definitely right
I understand that as meaning that faithful catholics shouldn’t take Pr(evolution)=1.
and from the things they are willing to call definitely right I don’t think it’s tenable to take this as meaning only that one shouldn’t literally take Pr(evolution)=1
The thing is, the things that they are willing to consider as definitely right are things like the divine origin of Christianity; and as far as I understand it, they do expect faithful catholics to take Pr(Christianity has a divine origin)=1.
Unfortunately, I think what you’re clarifying isn’t what I was asking about :-). Let P be the proposition “as far as scientifically observable consequences go, evolution behaves as if it’s entirely natural and undesigned”. You and I agree that a theist can consistently believe P; call this thing that we believe Q. (Perhaps you also believe P, as I do, but that’s a separate question.) You made a remark about the RCC (which has spawned a discussion entirely out of proportion to the importance of that remark in anyone’s arguments, but no matter!) which I interpreted as saying that the RCC’s official position is P, whereas in fact perhaps you were saying that the RCC’s official position is Q (or perhaps the closely related Q’, which says that a good Catholic can consistently believe P).
So my question was: were you saying that the RCC’s position is (something like) P, or that the RCC’s position is (something like) Q?
Pr(...) = 1
I agree that HG can be read as saying faithful Catholics mustn’t take Pr(evolution)=1 but must take Pr(souls)=1 (where both “evolution” and “souls” are brief abbreviations for more complicated things, of course). I suppose what I was getting at is that saying “don’t take Pr(X)=1” effectively means quite different things depending on whether the community you’re addressing is in the habit of taking Pr(various things)=1 or scrupulously avoids it as e.g. LW tends to for good reason; and the fact that HG firmly endorses taking some probabilities to be 1 indicates that it’s in the former camp, which to me suggests that HG is saying not what an LWer would express by “don’t take Pr(evolution)=1″ but something more like “don’t treat evolution as definitely true in the same sort of way as you treat other ordinary things as definitely true”.
But it’s possible, as you say, that actually the position being sketched in HG would be, if written out with more care, something more like this: there are essential dogmas of RC faith, for which one must assign p=1; there are ordinary statements of fact, like (ha!) “the earth orbits the sun”, for which one would be ill-advised to assign p=1 but the RCC doesn’t take any particular position on that question; but for evolution the RCC specifically says not to take p=1 but leaves open the possibility of taking p=1-10^-20 or something.
I suspect these are questions that have no answers, in the following sense: senior RC clergy don’t generally think in terms that correspond so directly to the very quantitative probabilistic approach commonly taken here as to enable a clear distinction between p=1 and p=1-10^-20, etc., and any “translation” that makes them out to have been making statements in those quantitative probabilistic terms is liable to misrepresent their meaning. (E.g., p=1, as such, means that absolutely no possible evidence would change your mind, but I think Pius XII could probably have imagined possible happenings that would have convinced him that God doesn’t after all directly attach souls to human bodies.)
So my question was: were you saying that the RCC’s position is (something like) P, or that the RCC’s position is (something like) Q?
Something almost exactly like Q’.
But it’s possible, as you say, that actually the position being sketched in HG would be, if written out with more care, something more like this: there are essential dogmas of RC faith, for which one must assign p=1; there are ordinary statements of fact, like (ha!) “the earth orbits the sun”, for which one would be ill-advised to assign p=1 but the RCC doesn’t take any particular position on that question; but for evolution the RCC specifically says not to take p=1 but leaves open the possibility of taking p=1-10^-20 or something.
I get the impression they were hinting at something more like Pr(evolution)=0.9, which is a figure entirely unsupported by anything in the text and involves me taking a guess, but apart from that this is pretty much exactly how I read it, yes. (With the note that the only reason the RCC is specifically calling out evolution is because there’s been such a brouhaha over it from the protestant churches that staying silent on the matter would have been bad politics).
senior RC clergy don’t generally think in terms that correspond so directly to the very quantitative probabilistic approach commonly taken here as to enable a clear distinction between p=1 and p=1-10^-20, etc.
While there may very well be senior clergy who do think in such terms (I wouldn’t know, I’ve never met any seriously senior clergy) this is largely why I think that something like p=0.9 is probably closer to the intended reading. (Or p=0.95, or even p=0.99)
(E.g., p=1, as such, means that absolutely no possible evidence would change your mind, but I think Pius XII could probably have imagined possible happenings that would have convinced him that God doesn’t after all directly attach souls to human bodies.)
Even if so, I’m pretty sure that it wouldn’t be the official Vatican position that that probability can ever be anything less than one. (Politics, again; if the Pope ever admits to that p being less than one and someone runs a headline based on it...)
And if he does see such evidence, he has to consider the possibility that he is hallucinating, or being intentionally tricked by someone; if p is high enough, then it may very well be the case that any sufficiently convincing evidence will merely convince him to report to the nearest psychologist with complaints of extraordinarily detailed and persistent hallucinations.
OK; then many of my earlier comments in this thread (which were essentially arguing that the RCC’s position is very different from P) have been entirely not-to-the-point and have wasted everyone’s time. I repent in dust and ashes.
p=0.9
Yeah, this is roughly my reading too. (Maybe more like p=0.7 or something back in 1950 with Humani Generis.)
it wouldn’t be the official Vatican position that that probability can ever be anything less than one.
So much the worse for the Vatican, then. (But I think you’re probably right.)
The Church has no official statements about probability one way or another. There are certainly Catholics who think that the probability of their beliefs is one (which is insane), but typically they do not hold this by saying that no possible evidence would convince them. They say, “such and such would convince me that Catholicism is false, but such and such is absolutely impossible, and I am absolutely certain that it is absolutely impossible.”
On the other hand there are many far more reasonable Catholics who admit that their probability is less than one, admit that there is evidence that would convince them their beliefs are false, and admit that they might later observe the evidence. The Church has never said anything against such opinions (or against the first kind of opinion).
One person I know, whom pretty much everyone considers to be a devout and orthodox Catholic, told me that he would be happy with a probability of 30% (that is, he would be happy to believe with that probability, based on Pascal’s wager type reasoning). I suspect that in practice his personal probability is around 50%.
The discussion about probabilities was all concerning the following specific question: How should we interpret the language in, e.g., Humani Generis about how faithful Catholics are required not to hold that some things are definitely true but the RCC teaches that some other things are definitely true? For sure, no translation into LW-style probabilityese is going to reproduce the meaning exactly, but one might reasonably hope to approximate what the RC documents say in terms that make some kind of sense to rationalists.
I think you need to understand that in terms of doxastic voluntarism. The Church holds that faith is voluntary, so that people can reasonably be praised or blamed for what they believe. They may not say it explicitly about other kinds of belief, but if they are right about religious beliefs, it would probably also be true that accepting or rejecting the theory of evolution (and any other similar thing) is also voluntary.
Given that account of belief, saying “you are obliged to say that this is definitely true and that this other thing is at least not definitely true,” is a statement about the choices you should make. You should choose to say (according to Pius XII), “Christianity comes from God,” and “Christianity definitely comes from God,” but not (according to Pius XII), “The theory of evolution applied to human beings is definitely true.”
Because it’s a question of choices, probability is not really relevant one way or another (except in the sense that the probability that something is true might be one reason that should affect whether or not you say something). That is why I gave the example of someone who estimates the chance of his beliefs being right, based on the evidence, to be about 50%. But despite that he chooses to say “this is simply true,” probably based on various moral considerations. Kind of like you might want to believe your brother about something rather than saying he is lying, not because of strong evidence for that, but because it’s hurtful to say “you’re lying.”
If this account is correct, the reason you can’t translate statements like that into statements resembling claims about probability is because that is simply not what they are about.
Rationalists say many things which have similar moral implications, and which don’t ultimately make a lot of sense apart from a similar doxastic voluntarism (e.g. “you ought to update on evidence,” which implies that you can and should choose to do so), but most people don’t accept an account like this explicitly. If you don’t accept doxastic voluntarism, you should simply say that the Catholic Church’s statements about such things are presuming an incorrect theory of belief, and just don’t make any sense apart from that theory.
(I agree with doxastic voluntarism, so such statements do make sense to me, whatever I happen to think about them on an object level.)
Rationalists say many things which have similar moral implications [...] e.g. “you ought to update on evidence”
When I say “you ought to update on evidence” I’m fairly sure I am neither endorsing doxastic voluntarism nor making a claim about the morality of updating (or not) on evidence. Rather, I mean that if you update appropriately on evidence then your beliefs will, over time, tend to grow more accurate compared with the beliefs you would hold if you didn’t update appropriately on evidence, and that this is likely to benefit whatever goals you may have. (I might add that it benefits other people for your beliefs to be accurate, so there is some moral import to whether you update on evidence, but that’s not what I would mean by “ought”.) Is it a pointless thing to say if we don’t get to choose what we believe? Not if we have more choice about what overall strategy to use when adjusting our beliefs than we have about individual beliefs, which I think may well be the case.
(As to the actual question of doxastic voluntarism, I think it’s clear that it comes in degrees and that the truth isn’t right at either extreme. I don’t believe either of us could, right now, decide to believe that grass is pink and forthwith start doing so; but I’m pretty sure either of us could incline ourselves more toward believing (say) that Charles Dickens was born in 1834 simply by repeating “Charles Dickens was born in 1834” in a confident tone of voice fifty times. Choose another example if you happen already to have a confident opinion about whether Dickens was born in 1834.)
I am fairly sure that many rationalists do in fact make claims about updating on evidence with moral implications, even if you do not intend those implications yourself. But in any case, even your response implies a certain degree of voluntariness, if it is possible to adopt an overall strategy of adjusting our beliefs; if it were totally involuntary, we could not affect the strategy (and in fact you agree in the second part that it is not totally involuntary.)
I agree that in the way people ordinarily mean it, I could not start to believe that grass is pink. But I also could not go and kill myself right now. That doesn’t make not killing myself involuntary, since the reason is that I think it would be bad to kill myself. The case of the grass might be different, and it might be impossible to start to believe that in a stronger sense. In other discussion of this issue someone compared it to holding your hand in a fire until it is burned off; that might well be a physical impossibility, not just a question of thinking that it is bad.
But even in the case of holding your hand in a fire, I would see that as a certain kind of desire (to pull your hand away), even if it is one that we cannot resist with our conscious desires, and the case of belief seems pretty similar. This might just be a question of how much you are willing to strain an analogy.
It’s not as if “belief” is a name for one objective thing in the world which is either there or not. There are a whole bunch of things, words, actions, thoughts, and feelings, and we call various patterns of these things a “belief.” Some of these things are voluntary and some are not. Simply for consistency I choose to call the voluntary parts of that pattern “belief” and exclude the other parts, at least when there is competition between them. According to this way of speaking, I could choose to believe that Dickens was born in 1834, even right now, if I had a motive to do so. But that would not affect the involuntary parts of my assessment, and you might prefer to call it something else (e.g. “belief in belief”).
I think a lot of that is the Vatican being really really cautious. They’re ultra-cautious about just about everything they say (largely, I think, because they are well aware that (a) a lot of people will take what they say as gospel truth and (b) they don’t get to take anything back, or hardly ever, so if they endorse evolution in some form and then a few decades later a scientist comes back and presents some improvement on the theory that contradicts that form then they will look silly).
So, yeah. What I’m reading into that is that they’re not saying it’s definitely true (in the same way as they do say it’s definitely true that God exists) but they are saying it looks like it just might be.
As well as being ultra-cautious about evolution, Humani Generis says these things (emphasis mine):
(as well as many other things that don’t appear to me at all ultra-cautious, but where the language is less clear-cut). So this isn’t the result of any general policy of ultra-caution. They are being extra-ultra-cautious about evolution specifically. That was in 1950, and they are less cautious now, but still very cautious. This is why I say their position is notably different from that of naturalistic evolutionary biologists.
… Oh, wait. Have I misunderstood you? If so, we may be arguing at cross-purposes. Here’s our exchange from upthread:
When you said “that”, did you mean (1) “the exact same view of evolution as an atheist” or (2) “the idea that there’s no fundamental reason why a theist couldn’t, etc.”? I’ve been assuming #1 but maybe you meant #2, in which case our disagreement is less sharp than I thought. On #2, my impression is that the Vatican hasn’t said or implied much about what theists as such can reasonably believe about evolution; they’re concerned, rather, with what faithful Catholics can reasonably believe about evolution; and what they’ve said about the latter is, inter alia, that faithful Catholics mustn’t regard it as definitely right (a position that I don’t think is negated by JP2′s statement before the Pontifical Academy of Sciences), and from the things they are willing to call definitely right I don’t think it’s tenable to take this as meaning only that one shouldn’t literally take Pr(evolution)=1. So I don’t think the Vatican thinks it acceptable for Catholics to think about evolution in the same way as most atheists do. Again, what they think about theists more broadly is hard to tell.
From the same document (of the International Theological Commission) that I quoted earlier:
“Since it has been demonstrated that all living organisms on earth are genetically related, it is virtually certain that all living organisms have descended from this first organism.” Given Ratzinger’s approval of that document I don’t think you can reasonably say that a Catholic who thinks that evolution is definitely right (in the ordinary sense of thinking that something is definitely right) is not a faithful Catholic.
Well … the very next sentence of that document is this:
and while that’s pretty positive about evolution it seems not to be saying that evolution is definitely right. I think what’s going on here is that the authors of that document are happy being very confident about common descent but not so happy being equally confident about evolution.
As to just what sort of evolution, here’s an extract from further on in that document:
As the section of that document that you quoted before makes clear, giving God a “truly causal role” doesn’t necessarily mean endorsing divine intervention. Section 68 -- the one before the one you quoted before—suggests what alternatives the authors had in mind, most notably the idea that he designed the universe in such a way that its natural operation would produce particular results.
This, again, is quite far from any view of evolution that would be endorsed by naturalists.
Even in section 68, I don’t see them saying that God necessarily “designed the universe in such a way that its natural operation would produce particular results,” in any sense stronger than the one which would be absolutely necessary for someone who believes that God is omnipotent and omniscient and the cause of everything that happens. In other words, given that you believe such things about God, then if you see a rock fall and land on the ground, you must believe that God wanted it on the ground. But that wouldn’t necessarily imply that it would have bothered God if it landed in the water instead.
Obviously naturalists would not accept God’s design even in this sense. But it is not a scientific theory one way or another and makes no differences in what you expect to find in nature. So that would still allow for someone to say that naturalistic evolution is definitely true with respect to every prediction that it makes.
Also, I agree that in practice, at least in other places, there is the implication that the world was designed (at least by initial conditions) for the sake of some results rather than others. This comes up especially in regard to marriage and sexuality. However, I don’t see that proposed in any dogmatic way, and it seems to be wishful thinking: if it is objectively by chance that reproduction works the specific way it does, then it becomes harder or impossible to justify Catholic sexual morality. For example, if human beings had developed by evolution in such a way that sexual reproduction required one partner killing the other, it would be obviously justified for them to make technological changes in the way they reproduce.
I’m not sure what sense you have in mind. It seems to me that taking seriously the idea that God is omniscient and the cause of everything that happens more or less commits one to seeing everything as designed by God to achieve whatever his purposes might be.
It is fairly common to say: no, despite having that power God conferred free will upon some of his creatures, so that what they do is not chosen by him. I’m not sure that actually makes sense when looked at clearly, but in any case it seems hard to apply this idea to the laws of nature.
In any case, the document we’re discussing seems to me to be saying that God may guide natural processes like evolution by being a “cause of causes”, and setting up the web of natural causation so as to achieve his ends.
(I don’t mean to imply that it’s saying he did so in such a way as to predetermine everything that happens, by the way; one can imagine God setting up a world that operates at random, and optimizing for a particular probability distribution or something of the kind.)
I’m not sure if we’re disagreeing about anything. I’m not saying that any Church authority has said that “the process of evolution looks exactly like a naturalistic process”, but that what they do say is consistent with this being true. Even assuming God had some motive for setting up things the way they are, how would that imply something in the process of evolution that doesn’t look naturalistic?
I certainly agree that if you say God is relevant at all, that is not something that naturalism would say. But it also doesn’t seem to mean anything concrete about the process.
Neither am I. I think that
in so far as the RCC has a position on the actual facts of biological evolution (as opposed to a position on what the Catholic faithful are supposed to think about them):
it seems to me fairly clearly distinguishable from any position a typical atheist evolutionist would adopt, even as regards observable questions like how likely it is that clear evidence of non-natural processes in evolution will ever turn up, though it’s hard to be certain because the official documents carefully avoid being too definite on such matters, and
I bet the senior RC clergy responsible for these documents hold positions more clearly distinguishable from those of typical atheist evolutionists, even as regards etc.; but
I suspect many of them have at least a suspicion that the scientific evidence for naturalist-looking evolution is only ever going to get better, and that clear signs of any kind of divine design in natural organisms are never going to show up.
as regards the RCC’s position on what the Catholic faithful are supposed to think:
I don’t think they are forbidden to adopt positions that, as regards etc., are indistinguishable from those of a typical atheist evolutionist, but
those official documents seem intended to discourage them from holding such positions, and
such positions seem permitted only (I insist on saying!) grudgingly. In particular:
until recently the Catholic faithful were explicitly forbidden to adopt such positions (on account of, e.g., what Humani Generis says about not regarding evolution as definitely correct), and
I strongly suspect that if even a modest amount of credible scientific evidence pointing in the direction of “intelligent design” were to show up, the RCC would return to that sort of stance.
(Not all of those things are directly related to the questions we were discussing.) Does that help?
Ok. I think I agree at least mostly with this summary, although I might qualify a few points.
In itself it’s likely that someone who believes in God will estimate a higher probability of evidence of non-natural processes in evolution than for an atheist. But there is also the third point you mention, namely that even theists may notice that there is currently no such evidence and may suspect that there never will be any. So this might mitigate the difference in their expectations somewhat.
Regarding what is grudgingly permitted or what is encouraged, I think this is less about probability assignments about the facts at issue, and more about the probability that a belief will tend to keep people in the Church or to lead to them leaving the Church. I think this is true even when the Church authorities are explicitly aware that a belief is probably false, at least in some cases. They still will not discourage that belief if it makes it more likely for someone to stay in the Church, unless there is some other motive for discouraging it (e.g. if the belief is very obviously ridiculous, they may discourage it because it could make the Church look bad.)
Yes; there are some things that the Vatican is extremely certain of (e.g. the divine origin of the Christian religion). Their ultra-caution extends to everything else—a rather large category which just so happens to include evolution.
I don’t think they’re less cautious, I just think they recognise that there’s more evidence. At the very least, the fact that no-ones convincingly refuted it in the last sixty-odd years despite all the attention being paid to it counts for quite a bit.
I meant that there’s no reason why a theist can’t hold a view of evolution that makes exactly the same predictions in all circumstances as an atheist does. Naturally, the theist’s view will incorporate God as having (at the very least) set up the natural laws that permit it, while the atheist will presumably have those laws simply existing with no particular cause; but they can both agree on what those laws are.
I understand that as meaning that faithful catholics shouldn’t take Pr(evolution)=1.
The thing is, the things that they are willing to consider as definitely right are things like the divine origin of Christianity; and as far as I understand it, they do expect faithful catholics to take Pr(Christianity has a divine origin)=1.
Unfortunately, I think what you’re clarifying isn’t what I was asking about :-). Let P be the proposition “as far as scientifically observable consequences go, evolution behaves as if it’s entirely natural and undesigned”. You and I agree that a theist can consistently believe P; call this thing that we believe Q. (Perhaps you also believe P, as I do, but that’s a separate question.) You made a remark about the RCC (which has spawned a discussion entirely out of proportion to the importance of that remark in anyone’s arguments, but no matter!) which I interpreted as saying that the RCC’s official position is P, whereas in fact perhaps you were saying that the RCC’s official position is Q (or perhaps the closely related Q’, which says that a good Catholic can consistently believe P).
So my question was: were you saying that the RCC’s position is (something like) P, or that the RCC’s position is (something like) Q?
I agree that HG can be read as saying faithful Catholics mustn’t take Pr(evolution)=1 but must take Pr(souls)=1 (where both “evolution” and “souls” are brief abbreviations for more complicated things, of course). I suppose what I was getting at is that saying “don’t take Pr(X)=1” effectively means quite different things depending on whether the community you’re addressing is in the habit of taking Pr(various things)=1 or scrupulously avoids it as e.g. LW tends to for good reason; and the fact that HG firmly endorses taking some probabilities to be 1 indicates that it’s in the former camp, which to me suggests that HG is saying not what an LWer would express by “don’t take Pr(evolution)=1″ but something more like “don’t treat evolution as definitely true in the same sort of way as you treat other ordinary things as definitely true”.
But it’s possible, as you say, that actually the position being sketched in HG would be, if written out with more care, something more like this: there are essential dogmas of RC faith, for which one must assign p=1; there are ordinary statements of fact, like (ha!) “the earth orbits the sun”, for which one would be ill-advised to assign p=1 but the RCC doesn’t take any particular position on that question; but for evolution the RCC specifically says not to take p=1 but leaves open the possibility of taking p=1-10^-20 or something.
I suspect these are questions that have no answers, in the following sense: senior RC clergy don’t generally think in terms that correspond so directly to the very quantitative probabilistic approach commonly taken here as to enable a clear distinction between p=1 and p=1-10^-20, etc., and any “translation” that makes them out to have been making statements in those quantitative probabilistic terms is liable to misrepresent their meaning. (E.g., p=1, as such, means that absolutely no possible evidence would change your mind, but I think Pius XII could probably have imagined possible happenings that would have convinced him that God doesn’t after all directly attach souls to human bodies.)
Something almost exactly like Q’.
I get the impression they were hinting at something more like Pr(evolution)=0.9, which is a figure entirely unsupported by anything in the text and involves me taking a guess, but apart from that this is pretty much exactly how I read it, yes. (With the note that the only reason the RCC is specifically calling out evolution is because there’s been such a brouhaha over it from the protestant churches that staying silent on the matter would have been bad politics).
While there may very well be senior clergy who do think in such terms (I wouldn’t know, I’ve never met any seriously senior clergy) this is largely why I think that something like p=0.9 is probably closer to the intended reading. (Or p=0.95, or even p=0.99)
Even if so, I’m pretty sure that it wouldn’t be the official Vatican position that that probability can ever be anything less than one. (Politics, again; if the Pope ever admits to that p being less than one and someone runs a headline based on it...)
And if he does see such evidence, he has to consider the possibility that he is hallucinating, or being intentionally tricked by someone; if p is high enough, then it may very well be the case that any sufficiently convincing evidence will merely convince him to report to the nearest psychologist with complaints of extraordinarily detailed and persistent hallucinations.
OK; then many of my earlier comments in this thread (which were essentially arguing that the RCC’s position is very different from P) have been entirely not-to-the-point and have wasted everyone’s time. I repent in dust and ashes.
Yeah, this is roughly my reading too. (Maybe more like p=0.7 or something back in 1950 with Humani Generis.)
So much the worse for the Vatican, then. (But I think you’re probably right.)
Something in that general order of magnitude is probably more-or-less right.
...I think we’ve pretty much come to agreement on these points, then.
The Church has no official statements about probability one way or another. There are certainly Catholics who think that the probability of their beliefs is one (which is insane), but typically they do not hold this by saying that no possible evidence would convince them. They say, “such and such would convince me that Catholicism is false, but such and such is absolutely impossible, and I am absolutely certain that it is absolutely impossible.”
On the other hand there are many far more reasonable Catholics who admit that their probability is less than one, admit that there is evidence that would convince them their beliefs are false, and admit that they might later observe the evidence. The Church has never said anything against such opinions (or against the first kind of opinion).
One person I know, whom pretty much everyone considers to be a devout and orthodox Catholic, told me that he would be happy with a probability of 30% (that is, he would be happy to believe with that probability, based on Pascal’s wager type reasoning). I suspect that in practice his personal probability is around 50%.
The discussion about probabilities was all concerning the following specific question: How should we interpret the language in, e.g., Humani Generis about how faithful Catholics are required not to hold that some things are definitely true but the RCC teaches that some other things are definitely true? For sure, no translation into LW-style probabilityese is going to reproduce the meaning exactly, but one might reasonably hope to approximate what the RC documents say in terms that make some kind of sense to rationalists.
I think you need to understand that in terms of doxastic voluntarism. The Church holds that faith is voluntary, so that people can reasonably be praised or blamed for what they believe. They may not say it explicitly about other kinds of belief, but if they are right about religious beliefs, it would probably also be true that accepting or rejecting the theory of evolution (and any other similar thing) is also voluntary.
Given that account of belief, saying “you are obliged to say that this is definitely true and that this other thing is at least not definitely true,” is a statement about the choices you should make. You should choose to say (according to Pius XII), “Christianity comes from God,” and “Christianity definitely comes from God,” but not (according to Pius XII), “The theory of evolution applied to human beings is definitely true.”
Because it’s a question of choices, probability is not really relevant one way or another (except in the sense that the probability that something is true might be one reason that should affect whether or not you say something). That is why I gave the example of someone who estimates the chance of his beliefs being right, based on the evidence, to be about 50%. But despite that he chooses to say “this is simply true,” probably based on various moral considerations. Kind of like you might want to believe your brother about something rather than saying he is lying, not because of strong evidence for that, but because it’s hurtful to say “you’re lying.”
If this account is correct, the reason you can’t translate statements like that into statements resembling claims about probability is because that is simply not what they are about.
Rationalists say many things which have similar moral implications, and which don’t ultimately make a lot of sense apart from a similar doxastic voluntarism (e.g. “you ought to update on evidence,” which implies that you can and should choose to do so), but most people don’t accept an account like this explicitly. If you don’t accept doxastic voluntarism, you should simply say that the Catholic Church’s statements about such things are presuming an incorrect theory of belief, and just don’t make any sense apart from that theory.
(I agree with doxastic voluntarism, so such statements do make sense to me, whatever I happen to think about them on an object level.)
When I say “you ought to update on evidence” I’m fairly sure I am neither endorsing doxastic voluntarism nor making a claim about the morality of updating (or not) on evidence. Rather, I mean that if you update appropriately on evidence then your beliefs will, over time, tend to grow more accurate compared with the beliefs you would hold if you didn’t update appropriately on evidence, and that this is likely to benefit whatever goals you may have. (I might add that it benefits other people for your beliefs to be accurate, so there is some moral import to whether you update on evidence, but that’s not what I would mean by “ought”.) Is it a pointless thing to say if we don’t get to choose what we believe? Not if we have more choice about what overall strategy to use when adjusting our beliefs than we have about individual beliefs, which I think may well be the case.
(As to the actual question of doxastic voluntarism, I think it’s clear that it comes in degrees and that the truth isn’t right at either extreme. I don’t believe either of us could, right now, decide to believe that grass is pink and forthwith start doing so; but I’m pretty sure either of us could incline ourselves more toward believing (say) that Charles Dickens was born in 1834 simply by repeating “Charles Dickens was born in 1834” in a confident tone of voice fifty times. Choose another example if you happen already to have a confident opinion about whether Dickens was born in 1834.)
I am fairly sure that many rationalists do in fact make claims about updating on evidence with moral implications, even if you do not intend those implications yourself. But in any case, even your response implies a certain degree of voluntariness, if it is possible to adopt an overall strategy of adjusting our beliefs; if it were totally involuntary, we could not affect the strategy (and in fact you agree in the second part that it is not totally involuntary.)
I agree that in the way people ordinarily mean it, I could not start to believe that grass is pink. But I also could not go and kill myself right now. That doesn’t make not killing myself involuntary, since the reason is that I think it would be bad to kill myself. The case of the grass might be different, and it might be impossible to start to believe that in a stronger sense. In other discussion of this issue someone compared it to holding your hand in a fire until it is burned off; that might well be a physical impossibility, not just a question of thinking that it is bad.
But even in the case of holding your hand in a fire, I would see that as a certain kind of desire (to pull your hand away), even if it is one that we cannot resist with our conscious desires, and the case of belief seems pretty similar. This might just be a question of how much you are willing to strain an analogy.
It’s not as if “belief” is a name for one objective thing in the world which is either there or not. There are a whole bunch of things, words, actions, thoughts, and feelings, and we call various patterns of these things a “belief.” Some of these things are voluntary and some are not. Simply for consistency I choose to call the voluntary parts of that pattern “belief” and exclude the other parts, at least when there is competition between them. According to this way of speaking, I could choose to believe that Dickens was born in 1834, even right now, if I had a motive to do so. But that would not affect the involuntary parts of my assessment, and you might prefer to call it something else (e.g. “belief in belief”).