Ongoing Conversation with Jonathan McLatchie

including what would convince me, a visit from Jean Luc Picard, and more

In #religion

I'd like to thank Jonathan McLatchie for the detailed response to my two-part response.

If you're following along, we have:

Here I try to go through somewhat systematically, but by the end there are lot of interesting directions. Hope some of this is fruitful!

Given Blais’ apparent interest in the proper application of Bayesian probability theory, why does Blais not say a word about Dillahunty’s incredibly poor understanding of it, which was made plain at numerous points during his debate with me?

At this response, I went and rewatched the Dillahunty debate and the debate review McLatchie had with Braxton Hunter. I haven't gone back to do a detailed response to that debate, but in my OP I was simply referring to things I heard in that debate that I also heard in my own discussion with McLatchie and in discussion with Pearce. I was focussing on the common points being brought up, and not addressed, and not on the score of any particular debate.

According to a frequentist metric, this would be judged to be an extraordinary claim. However, in the case of spontaneous proton decay, there may be theoretical considerations that inform our background knowledge and therefore increase the event’s prior probability.

The hypothesis of spontaneous proton decay, despite its having never been observed, is not a wild guess, but rather has a theoretical underpinning.

I agree here. It is an extraordinary claim! So we need, as Sagan says, extraordinary evidence. We can be more confident when there is a theoretical expectation, built on many other experiments that have been confirmed.

Likewise with the resurrection, the idea that Jesus rose from the dead, even before consideration of the direct evidence, is not some wild guess without any relevant background considerations. Rather, it is made plausible by other background considerations, as enumerated in my previous essay.

This is where the comparison fails -- it's the nature of the "background considerations" or "theoretical underpinning" that makes it strikingly different. Both are incredibly rare events, by anyone's standard, and any evidence that could potentially be interpreted as the result of more common events should be suspect. That's why science has controls for alternative effects, that's why science designs experiments to rule out alternatives by making specific predictions of which events will happen under which circumstances, etc...

considerations other than frequency can and do bear on the prior probability of an event occurring

McLatchie is correct, but perhaps it's a little better to recognize that one person's prior is a previous person's posterior? This is the nature of cumulative cases, I believe, which is what McLatchie typically espouses. If we start from scratch, then both proton decay and the Resurrection of Jesus are rare events -- one might even argue that the proton decay, a-priori is less likely. But now we start layering on our growing understanding of the world. The Standard Model is the result of a century of painstaking experiments to construct an admittedly unintuitive yet outrageously accurate model of the world, which has been confirmed by more observations than I can count. And it doesn't even predict proton decay! It is in extensions of the Standard Model, all of which must be consistent with the Standard Model and General Relativity -- our best understanding of the universe -- which predict proton decay. We are as confident in those claims as we are in the massive amount of supporting experiments and confirmed predictions.

If we start doing the same for the Resurrection, we get a very different story. We have a claim that directly violates our understanding of how the universe works, against a backdrop of many cultures making similar claims. The best (only?) evidence we have are texts from a pre-scientific world, from authors we can only attempt to infer, with very little information of their providence. McLatchie might be inclined to add evidence for intelligent design and fine tuning, but these concepts have not convinced the experts in those fields, so they are at best not well understood and do not count as significant evidence. We also have many other cases of claims written in this text -- handling snakes, healing in Jesus' name, demon possession, etc... which have since been demonstrated to be false and not anything comparable that would indicate anything other than human construction. This is similar to alien abduction cases never coming up with anything that would indicate alien tech or alien knowledge -- it's always completely consistent with the knowledge of the people at the time and place.

"The laws of nature, we must say, describe the ways in which the world — including, of course, human beings — works when left to itself, when not interfered with." - John Mackie

This is a terrible way to view scientific explanations. It tries to have a "get out of jail free" card for whatever one feels like injecting into the system -- fairies, gods, magic, etc... But I can see the power of the analogy. Correct me if I'm wrong, but McLatchie is seeing the world (i.e. universe) like a clock with lots of gears working together. We can describe the workings of the clock perfectly, but then if some outside agent (e.g. a person) comes in to wind it, replace a gear, or make a something run backwards for a bit that isn't in the description of the working clock, so isn't a violation of that description? I prefer to think "natural law" as the list of things that we have to describe what goes on in the clock, from the perspective of someone in the clock. We can see some gears, we need to infer the existence of other gears that we don't see, in order to construct the workings of the clock. Anything that breaks this pattern is a violation of something on that list. The "natural laws" are descriptive not prescriptive. We can propose that the observed violation is due to our misunderstanding of the gears, and propose some other configurations. We can propose that there is some outside agent. We can propose other things. Here's where the analogy lands -- in every single case where someone has proposed an agent, and we've been able to conclusively show what the cause was, it was another gear and not an agent. Every. single. time. Trying to say that a miracle is not a violation of the laws of nature, I think, is trying to excuse oneself ahead of time for something that really should be dealt with upfront -- miracles are a violation of the patterns of causes and effects we have come to expect from the universe, and are thus extremely unlikely at this point given our understanding. It is no coincidence, I think, that the strongest cases for theism still lie only in those fields where there is a lot of uncertainty -- origin of life, origin of the universe, etc...

Enter Jean Luc

Suppose you are walking in a forest and stumble upon a shack that, upon initial inspection, appears to be uninhabited. Nonetheless, you decide to investigate. As you open the door, you notice a table, upon which there is a tumbler containing Earl Grey tea, which is still steeping. Now, on the hypothesis that the shack is inhabited, does it predict with high probability the presence of the steeping Earl Grey tea on the table? Hardly! Nonetheless, this observation is very strong evidence that the shack is inhabited, since on that supposition the presence of the tea (even though improbable) is far, far more probable than it would be on the falsehood of that hypothesis. What is important, then, is the likelihood ratio of the probabilities.

We do have to watch out about reference classes here, but I like this picture. It's not likelihood ratio that is always critical, as we see if I walk through the process. We come onto a shack -- so we already know there was some human activity there at some point in the past. We are considering two models -- inhabited (\(H\)) or uninhabited (\(U\)). Given that the shack is out in the forest, perhaps our prior is somewhat low for inhabited, so we'd have something like

$$ \begin{aligned} P(H)&=1/10 \\ P(U)&=9/10 \end{aligned} $$

Upon entering, we have hot tea on the table. Suddenly we have something like,

$$ \begin{aligned} P(H|\text{hot tea})&\sim P(\text{hot tea}|H) \times 1/10 \\ P(U\text{hot tea})&\sim P(\text{hot tea}|U)\times 9/10 \end{aligned} $$

The likelihood of tea given inhabited might be low, \(P(\text{hot tea}|H) = 1/1000\) as McLatchie says ("on the hypothesis that the shack is inhabited, does it predict with high probability the presence of the steeping Earl Grey tea on the table? Hardly!"), but is far higher than the likelihood of tea given uninhabited might be low, \(P(\text{hot tea}|U) = 1/1,000,000\) and is plenty to overcome the modestly low prior,

$$ \begin{aligned} P(H|\text{hot tea})&\sim 1/1000 \times 1/10 = 1/10,000\\ P(U|\text{hot tea})&\sim 1,000,000\times 9/10 = 9/1,000,000\\ T&=109/1,000,000 \\ \end{aligned} $$


$$ \begin{aligned} P(H|\text{hot tea})&= 1/10,000/T = 100/109 = 92\%\\ P(U|\text{hot tea})&=9/1,000,000/T = 9/109 = 8\% \end{aligned} $$

If course the numbers are probably off, but the structure is correct. This seems to be McLatchie's point -- the likelihood ratio is the key factor! However, notice that it is both the prior and the likelihood that come in.

I think McLatchie and I are in agreement here, at least on this example. Now, if we had considered an additional model, that "it was Jean Luc Picard had visited, and had dropped off his 'Earl Grey, hot' before beaming back to the Enterprise", we could use the same approach. Under the Picard model (\(J\)) we actually expect Earl Grey (hot) specifically so it's likelihood is very high

$$ \begin{aligned} P(\text{hot tea}|J) &= 1/3 \end{aligned} $$

So are we going to admit that it is far more likely that Jean Luc had visited? Absolutely not -- because, prior to the data, we have a supremely low prior for him visiting. Focussing on the likelihoods makes one much more susceptible to outlandish claims, and "just-so" thinking. One can always come up with a model that predicts exactly the data one observes by just saying "it actually happened exactly this way", but this leads to fallacies because the priors are not handled well.

My Four Questions (and perhaps some more)

So then McLatchie responds to my four questions. Those questions were:

  1. Can you make a prediction of when miraculous healing, or any other miracles, will happen -- or is it always post-hoc?
  2. Can you make any description of a measurement that could be done, no matter how impractical, for directly confirming any of the predictions from the God-theory?
  3. You mentioned a case of a healing of Irene McDonald with multiple sclerosis, but I can't find the medical details (i.e. the actual doctor's reports, the detailed timeline, etc...). Same with the case of Barbara Schnyder. Can you provide those? (note -- some of your other medical miracle claims were suspect after I researched them)
  4. How did you determine that these people were healed by prayer and also by God? You can't answer "because they prayed and she was healed after" (post-hoc fallacy) and you can't answer "because they prayed to the Christian God", because some other God may have answered, or some other thing. You have to, in your explanation, be able to distinguish from the prayers that haven't worked, the cases where healing happened without prayer or with prayer to another God. Without this, you can't make a reasonable claim that God-did-it.

His answers, in short, were:

  1. it is not necessary
  2. it is not necessary
  3. it is not necessary
  4. correlation is good evidence of causation

He offers responses like

If parallel examples exist with such complete and enduring healing from MS without the involvement of prayer, that would significantly undermine these examples as evidence for special divine action.

but there isn't good evidence that the miraculous healing occurred in the first place. How about this case:

Greta Brandt was cured of Leukemia by aliens. Her doctor, Dr. Frans Wenderoth, confirms that she had the lethal disease and "something miraculous must have happened" for her to not have it anymore. She herself claims that she was abducted by aliens and while on the ship they cured her.

Do I believe this? Nope. Do I even think that the doctor's testimony is to be trusted? Not without better documentation. All we have are the claims. I can find a bunch more like this, but it is a waste of time, really.

Indeed, if it is the case (as many atheists allege) that unanswered prayer is evidence against the existence of God, then it necessarily follows that answered prayer is evidence that confirms the existence of God.

That's true, but it's terrible evidence. We have so many claims of healings but we have way more people who pray and go unanswered. Even with the claims of actual healings, there aren't many that could even in principle rule out natural causes. Even in that subset of the ones that in principle seem to be unexplainable, none of them have the necessary documentation or skeptical inquiry that allow us to rule out natural causes or demonstrate directly something other than natural causes. McLatchie isn't moved by alien abduction stories, but the same exact pattern exists there. It's the pattern of typical human bias.

Even the shack example above was introduced to demonstrate that one does not need "high probability predictions in order for it to be well evidentially supported", I would say that from my perspective it is necessary when one is comparing against models that do make high probability predictions.

What would it take to convince me?

This question came up in the Dillahunty debate, and is reprised in the Braxton discussion. Dillahunty has his go-to response of "I don't know what would convince me, but God would". In a sense, I understand his point of view. What would convince me that String Theory is true? I really don't know, but I know it will involve specific and unique predictions that can be verified even if I can't tell you ahead of time what those predictions would be -- that's the job of the person putting forward the model.

Also for me, it is usually (at least) a two-step process. The first step is just to determine if there is a "there there" -- is there anything to even take seriously? In the case of a miraculous healing claim or an alien abduction story, my first step is just to establish the facts of the story -- is there anything worth investigating, or anything even possible to investigate? This has generally come up empty, which is why I ask for medical documentation -- stories aren't enough. I've never gotten to the second step, where one has to explain the actual event, except in scientific contexts.

One can have compelling evidence even when a case could be rendered stronger with even more evidence.

Actually not, I think. There is no way you could convince me of a miraculous healing without medical documentation at a minimum. There is no way to convince me of a violation of physical law from historical documents alone. There are just too many alternatives, and we are awash in claims of healings and miracle claims (as Keener points out) but mighty thin on the ground for actual corroboration. The process of overturning our fundamental understanding involves specific and unique predictions that can be verified, a back and forth of peer review and skepticism, an honest evaluation of the uncertainties, etc.... Historical data is just not sufficient.

Like so many critics, Blais does not seem to appreciate the value of casualness in assessing historical reliability.

I agree here -- I don't appreciate the inference from casual agreements, because it all seems so post-hoc and unconstrained. At best, it is unclear. In history, it may be a useful technique because one has nothing better. To justify changing our fundamental understanding of the universe, it is thoroughly uncompelling.

A direct message to Jonathan McLatchie

Jonathan McLatchie, if you've gotten this far, please read this (maybe I'll make it a separate post as well to make it more accessible). You complained about some of Dillahunty's tactics in debate, and I agree for the most part. I also think there is one that you display that you should be aware of. It's not anything I think you do intentionally, but it has a particular effect you may not realize and I think it leads to frustration for you when others seemingly don't engage with your evidence. Perhaps by pointing it out, it will help you communicate your points better.

When you talk about the Bible most atheists hear this as if you are a rabid Star Trek fan or Harry Potter fan. You will have statements like:

However, as Timothy McGrew observes concerning the claimed resurrection of Jesus, “The witnesses are not all confined to one vantage point, as they were in the case of the stage magician.

There are actually various lines of evidence that support the historicity of Jesus’ death on the day of Passover, though time did not permit me to discuss them in the debate with Pearce. First, this is a detail attested by all four gospels and implied by Paul in 1 Corinthians 5:7. The evidence bearing on the substantial trustworthiness and scrupulousness of the gospel authors is also relevant here. This is not a detail that the gospel authors (or their sources) plausibly misremembered, since so many details in the gospels are connected to Jesus’ death being at the time of Passover. [emphasis mine]

This still leaves a few loose ends that need addressing. First, what does John mean when he says, “for that Sabbath was a high day?” I would argue that he means that it was a particularly special feast day, not just any Sabbath day, but Sabbath in Passover week.

Since atheists are not convinced of the story, despite your confidence that it was written by truthful accurate (yet unknown) authors, many of your defenses sound like this:

Of course there is a three-headed dog, because the books are accurate on those points where we can confirm them (e.g. there is a King's Cross Station), and Hermione is always truthful and accurate in her descriptions. The book describes multi-sensory experiences of the three-headed dog, by groups of people (Hagrid, Hermione, Ron, and Harry). The second book has casual coincidences which show that the authors of the two books were independent. There is no way that the experience they had of a three-headed dog could have plausibly been misremembered. How could you explain the cut in Snape's leg if the three-headed dog didn't do it? When Harry is at the zoo, and the snake winks to him, this may seem like a contradiction (snakes don't have eyelids), but when the author uses the word "wink" I'd argue that he means the definition of "To shine fitfully; twinkle.".

I am sure you won't see these as parallel yourself, but this is exactly how I hear your defenses for the most part. So, quoting long sections of the Bible to support your claim is as effective as reading chapters of Harry Potter to me. In a debate, when you read long passages in the Bible I take it as a huge waste of time and shows a lack of understanding of your opponents position. I don't think it is intentional, because I think you do it to be thorough, but it has that effect and it comes off as a kind of a dodge -- wasting time to avoid more direct addressing of the problems.

Perhaps this will help you understand where I'm coming from, which responses I can actually grapple with and which I just don't take seriously despite your confidence in them.