## Friday, December 08, 2017

### Do extraordinary claims require extraordinary evidence?

Ron said...

Mike Darus said...

The "h" is missing at the beginning of the link.

Starhopper said...

Hmm... and here I thought it was the Darwinists who were always searching for the "missing link"!

Jimmy S. M. said...

“extraordinary claims require extraordinary evidence” isn't a universal logical principle, it's a useful skeptical heuristic you can take or leave, at the risk of your own credulity. So the authors first claim is attacking a straw man.

The lottery example is terrible, we have evidence of lottery winners all the time- journalistic, photographic, testimonial. We can talk to these people today and cross examine them, if we truly doubted their existence.

But for anyone who doesn't think “extraordinary claims require extraordinary evidence,” I'm taking down payments on a solar system cruise in my luxury starliner.

Victor Reppert said...

Ron said...

Thanks for fixing the link. Depending on how you define “extraordinary” it is a necessary truth of probability theory that “extraordinary claims require extraordinary evidence.” If you retranslate the slogan to say: “claims with low prior probabilities require stronger evidence to make them probable than claims with higher prior probabilities.” Formally, if P(h) is low, you shouldn’t believe P(h) unless the ratio P(e|h)/P(e|~h) is sufficiently high, and as P(h) gets lower, the required evidential ratio get some higher.

John Earman’s book “Hume’s Abject Failure” criticizing Hume for saying “extraordinary claims require extraordinary evidence,” not because the slogan is false, but because it’s such a mathematical triviality that it barely needed saying. It amounts to saying no more than “you shouldn’t believe that something probably happened unless it probably happened.” Seems obvious, but you’d be surprised by how many people disagree with this common sense principle: https://infidels.org/library/modern/aron_lucas/hume.html

Starhopper said...

Ron,

Then you run into the insoluble problem that different people will assign differing probabilities to various claims. If I assign a probability of 1 to the statement "God is the Creator of Heaven and Earth, of all things visible and invisible," who can gainsay me?

Creator of the Stars of Night

Ron said...

Starhopper,

The issue of "how to assign probabilities" is a different issue than whether "extraordinary evidence requires extraordinary evidence." It doesn't sound like you disagree with the principle that extraordinary claims require extraordinary evidence. Rather you are saying that there is no agreed upon way of determining *whether* a claim is extraordinary to begin with. I suppose that is a conversation for another day, but there is a wealth of literature on how to assign prior probabilities in an objective way. As to your example of assigning a probability of 1 to theism, that would violate Cromwell's Rule that priors must be between 0 and 1

Starhopper said...

"Cromwell's Rule" is overruled by "Starhopper's Rule", which says the probability that the Earth goes round the Sun is 1, that the Orioles won this year's World Series is 0, and that Napoleon met his Waterloo is 1.

It is college dorm beer session nonsense to say that nothing can ever be asserted as fact.

Ron said...

I don’t think any epistemologist would say that knowledge require 100% certainty. It seems pretty bizarre to say that fact=probability of 1. If I’m 99.99% sure of something, I can’t say it’s a fact? Epistemologists define knowledge as justified true belief. That doesn’t require 100% certainty.

Even brain in vat or matrix scenarios are logically possible, and therefore have some nonzero probability. Of course, the probability is so low it can be safely ignored. By if you say that the probability is literally zero, then you’ve solved a variety of philosophy’s longest standing puzzles (problem of the external world realism, problem of other minds, problem of induction) and you should share your solution with the world.

Moreover, you can formally prove that there is a less than 100% probability the Orioles won the World Series. You learned this through evidence (saw it on tv, news, etc.). But it’s a simple consequence of confirmation theory that empirical evidence cannot confirm a hypothesis up to 1 unless the hypothesis started at 1 before you observed the evidence. But there was not a 100% probability that the Orioles would win before the World Series started, so it follows as a matter of mathematical fact that no evidence could confirm this all the way up to 1. It may be 99.99%, and we can comfortably call it a fact that we know, but it’s not 100%.

William said...

Bill's heuristic:

If a given unlikely future event which I currently consider possible is lower in probability than the chance I may be wrong about its possibility, actions based on that event becoming actual are unwarranted.

Ron said...

Bill,

That’s exactly right

Starhopper said...

That’s exactly right

Hmm... Does that mean it has a probability of 1?

grodrigues said...

"Hmm... Does that mean it has a probability of 1?"

That would be a violation of the Cromwell's rule. Grin.

Ron said...

“Hmm... Does that mean it has a probability of 1?“

Haha, got me! Rephrase: I’m extremely confident that you are right.

Starhopper said...

My comment was of course meant in fun, but it masks a more serious point. There are literally countless things about which we may safely have no doubt whatsoever, that we may know as fact. We ought not to emulate Pilate, scoffingly asking "What is truth?"

I am sitting down as I type this. 100% true - probability of 1.
It is cloudy outside right now - 100% true - probability of 1.
Most of the Earth's surface is covered by water - 100% true - probability of 1.
Grant was the 1st US president to serve 2 full terms since Washington - 100% true - probability of 1.
Rap does not deserve to be called "music" - 100% true - probability of 1.
Etc., etc.

Ron said...

Of course there are countless things which we can safely know to be facts. But that is not the same thing as knowing them with the certainty of logical tautologies. My point is not to say that we must doubt everything. Rather, my point is that we can safely say we “know” an endless list of things, and we dont need to deny basic rules of logic and probability to do this. Do you have anything to say about the *reasons* I have for denying that contingent empirical claims can have probabilities of 1?

Starhopper said...

Even brain in vat or matrix scenarios are logically possible

No, they are not. Only in science fiction, but they are not fit subjects for rational thought in the Real World, and have no place in intelligent discussions.

Moreover, you can formally prove that there is a less than 100% probability the Orioles won the World Series.

Only if you are the sort of person who goes in for whacko conspiracy theories - the kind of thinking that says the Sandy Hill massacre was faked. Again, not worth spending any time on.

I prefer to keep my thinking sane, thank you.

Hugo Pelland said...

Starhopper said:

"Hmm... and here I thought it was the Darwinists who were always searching for the "missing link"!"

"I prefer to keep my thinking sane, thank you."

I would love to hear your sane thinking behind that joke at the top.

Starhopper said...

Do jokes have sane thinking?

Hugo Pelland said...

Let me clarify: beyond the joke, I am curious to know what you believe and why, regarding Darwinian evolution. This relates to the exchange we had a few days ago regarding miracles. Just curious to know what you think.

Starhopper said...

First of all, as far as my belief in Christianity does, whether or not evolution is "true" is totally irrelevant. The origin of species would appear to have no bearing on the central issue of my faith, which is "Is Jesus the Son of God, and did He rise from the dead as recorded in the Gospels?" To be honest, I don't give the controversy that much attention.

That said, I am, for admittedly purely unscientific reasons, an extreme skeptic of evolution. Not a denier, mind you, though I do lean in that direction. I take this position for two admittedly quite "unscientific" reasons. First, the human body (and especially the brain) just seems way, way too complex to explain by any process other than purposeful design. Second (and related to the first objection), the universe does not seem to have been around long enough for such complexity as we do observe in nature to have resulted from any conceivable purely natural process. It's not even like we have 13.7 billion years to accomplish the fact, because current evolutionary theory says that multicellular life didn't arise on the Earth until (geologically speaking) quite recently.

But as I said, these are not "scientific" objections, and I am open to any reasonable explanation that can satisfy them.

Hugo Pelland said...

Got it, thanks for sharing. And I agree that it has little to do, if anything, with Christianity so that was really not the point of the question. FWIW, I do embrace the theory of evolution and find it to be, combined with what astrophysics about the origins of atoms and molecule, the most fascinating theory humans have discovered. It literally traces our history from stars that exploded all the way down to our human species.

Starhopper said...

Just came across this quote today, and here is as good a place as any in which to share it:

"Every rose is an autograph from the hand of the almighty God. Roses are visible proof that God is real and that it's possible for us mere mortals to get very, very close to the Divine."

(Theodore Parker, 19th Century Unitarian minister)

Starhopper said...

Oops. I meant to add at the end of my last posting that perhaps people who are forever looking for "extraordinary evidence" fail to see such right in front of their nose.

Hugo Pelland said...

What does that even mean "Every rose is an autograph from the hand of the almighty God" ?

Starhopper said...

Are you serious? If so, then you sadly have no poetry in your soul.

But in any case, the point of my quotation was that we are literally surrounded by the "extraordinary evidence" that some people are asking for, namely the mind-boggling complexity and profound beauty of the natural world.

Hugo Pelland said...

Sorry, I don't see beauty in willful ignorance written in poetic language. I argue that understanding how the universe works makes it even prettier, even more grandiose, even more poetic in many ways. Summoning the hand of an almighty god does not make it more poetic, but it can make it less poetic when it clouds one's judgement about what we know about the universe.

Claiming that the mind-boggling complexity and profound beauty of the natural world are evidence for an almighty god is actually an example of such clouding. It removes an element of truth from the world we live in, a world that came to be the way it is through natural means, without a guiding hand in sight, and that makes it even more extraordinary, even more wonderful, even more amazing, without being less beautiful or poetic to our eyes and soul.

Starhopper said...

that makes it even more amazing

In fact, so amazing that it makes it impossible to believe in it.

Hugo Pelland said...

Too bad... as I said above, we can trace our history, the history of all living things, from stars that exploded all the way down to today. This is not just some wild belief; that's what we know, as human beings living in the 21st century, with varying degrees of uncertainty along the way.

Can I ask what part you find impossible to believe?

Joe Hinman said...

Hugo read my essay "Evolution of the God concept"

in two parts it shows how to understand belief in God woven in with a naturalistic account of human evolution.

part 1

part 2

Joe Hinman said...

Claiming that the mind-boggling complexity and profound beauty of the natural world are evidence for an almighty god is actually an example of such clouding. It removes an element of truth from the world we live in, a world that came to be the way it is through natural means, without a guiding hand in sight, and that makes it even more extraordinary, even more wonderful, even more amazing, without being less beautiful or poetic to our eyes and soul.

no major adherent of the design argument bases the argument on the prettiness of nature.

old atheist trick evading the real arguments by high lighting the schlock ones and making that the issue,

why not debate me? let's have an organized debate with rules, challenge

Starhopper said...

an I ask what part you find impossible to believe?

The part where it all just came about by itself, that the universe is its own cause.

Hugo Pelland said...

Joe, thanks for the offer. It's intriguing... tell me more about what that entails.

Starhopper, that's besides the point I made regarding the history of our atoms, from stars to us. Statements about the universe's cause, or lack thereof, are very different and not something we can know, unlike our evolution.

Starhopper said...

Fair enough. Perhaps I should have phrased it that not only do I not believe in blind, purposeless, unguided evolution - I find it to be unbelievable.

Hugo Pelland said...

What do you find unbelievable? Or, while trying to not sound condescending, what do you not understand about evolution that renders it unbelievable to you?

Starhopper said...

I've already addressed this. I do not believe that enough time has elapsed in the history of the universe to account for the complexity that we see today in the ecosphere and in the human body.

Hugo Pelland said...

But that is so vague... again, I think you just don't understand some of it, because it's really not something to believe in per se, it's just science theories based on observations, something to know and understand.

Starhopper said...

"Vague" is not a valid criticism when one is discussing so large a subject.

Hugo Pelland said...

Well you are not specifying what part is unbelievable.

Time elapsed? There were over 3 billion years, so which part was "too fast"?

Unguided? Too complex? Which biological thing is unexplainable? (Only the brain or other things too?)

Hugo Pelland said...

P.s. not trying to convince you of anything btw, it's just interesting to hear what people accept or reject, and why. It's also kind of sad to be frank, as it's just a science like any other, but rejected, in the USA especially, for many varied reasons

Starhopper said...
This comment has been removed by the author.
Starhopper said...

(Edited for style and re-posted.)

I do not believe that the age of the universe is of sufficient age to account for the complexity observed in our planet's ecosystem or in the human body. And current evolutionary theory does not give us 13.7 billion years. It says that all we see today developed over the last quarter of a billion years. The blink of a cosmic eye, as it were.

Hugo Pelland said...

This is still so vague, so I will try one last time, as it's fascinating to me that you would simultaneously ignore what we know about the universe and use parts of that same knowledge to make a case for its rejection.

A super rough timeline goes like this:
- 13.7B years ago, the universe as we see it around us started; first hydrogen atoms basically
- Over the next few billion years, clouds of hydrogen collapsed on themselves, formed stars, some exploded in supernova to create all the atoms we know of, galaxies formed, more stars exploded, etc...
- 4.6B years ago, our star, the Sun, started to shine, along with a bunch of planets around it, including one we care a bit more about
- 3B years ago, first trace of life; unicellular organisms that developed more and more complex cell machinery, and even encompassing other tiny organisms within their cell membrane, mitochondria for instance
- 500-750M years ago, multi cellular organisms started to show up, which triggered a lot more variety and complexity than ever before
- 65M years ago, the famous dinosaur extinction, one of many to have happen over the years
- 2M years ago, estimate for the first homo sapiens sapiens, biologically identical, or almost, to us today

And that is pretty much where astrophysics, chemistry and biology stop having anything to say about how we evolved, from stars that exploded to human beings. The rest is history, anthropology, the study of what humans have been up to, but our biology has not changed that much since.

So... which of these steps, or perhaps missing intermediate steps, is unbelievable because it was too short?

And please note that I did not Google anything so I could be off, on some on these steps, but I know the general order of magnitude for the numbers I gave is correct. Because that' what I know; not just what I believe.

Joe Hinman said...

Hugo: "Joe, thanks for the offer. It's intriguing... tell me more about what that entails."

first of all i am still getting over pneumonia. Not real chipper. So this would be for next week or even latter.This is a standard format I use all the time. choose a resolution. i usually go with "resolved that belief in God is rationally warranted" meaning. Meaning I don;t have to prove that there actually is a God but that there are God arguments that are strong enough to intellectually justify placing confidence in the belief that god exists.

Let the reader be the judge.No declared winner. there are certain rules governing documentation, and speaker order.We can deal with all that if you are interested,we have a set number of speeches for each, so it has a beginning and ending.Interested?

Starhopper said...

which of these steps, or perhaps missing intermediate steps, is unbelievable because it was too short?

The final two. In a purely natural universe, either one ought to have taken tens or even hundreds of trillions of years to accomplish.

Hugo Pelland said...

Joe, hope you feel better soon! And yes, that sounds interesting. I will be travelling to India next week so I will be replying during what is the night in the US, but I should have time to do so.

Starhopper, ok, that's clearer now, thanks. But it's too bad that you don't understand our biological history.

Starhopper said...

Oh, I think I understand current theories about our biological history well enough. I just don't believe in them.

Hugo Pelland said...

Nah, you don't. It's not something to believe in; it's something to understand. Once you understand all the steps, all the lineage, you cannot not believe in it. It's like saying that you learned about how World War 2 happened, but you don't believe it did... it makes no sense. You could claim that you don't believe certain details about it, something an individual did or did not do for example, but you could not possibly not believe that the war happened.

Joe Hinman said...

The evolutionary emergence of life in and of itself proves nothing about God.