You Can't Disprove a Miracle

[ignoramus]

And now for our half time break .... try the Stoneleigh Sauvignon Blanc, only $10 a glass. Large box of maltesers for the price of a medium box, only $16!

[SteveII]

Kind of a laughable value too....90% that you'd see a crippled leg uncrippled -given miracles-?  How'd you come to that one, jesus uncrippling nine out of ten people and we just missed it?  There are ten answers to the question and jesus is nine of them?  It's happened on the third tuesday of the month and tuesday times three is nine?

You need to read more carefully. 

The 90% value P(E/H) is not the probability of a miracle. It is the probability that we would see E if H were true.

The hyposthesis (H) is that man was healed by Jesus. So you are saying that we should not see him walk if Jesus healed him?!?

[The Grand Nudger]

The probability we would see e -given what, again?  Given unity on the existence of miracles.  That jesus heals.  

Assuming miracles exist as part of an equation to determine the probability that something is a miracle, and by extension your use of the equation to determine..that miracles exist....is why this equation cannot be used in the manner you wish. As I said -way- back at the beginning, you're hiding your assertions in an equation. Your assertions rob the equation of it's validity when you try to turn the math into a logical proposition in natural language. If you could overcome that barrier (and really, it wouldn't be difficult to do that if you weren't so pigheaded) would leave you in a position where I would laugh at the values you set, as I did. If you found an amenable value, I would remind you, as I did at the start..that it's all for naught...as improbable things do happen.

There is no avenue here, anywhere, for you to establish what you hope to establish. Find some other way. This constant burden shifting bullshit is pointless. No one has to tell you anything...it's on you to do the work, to make miracles happen.

[robvalue]

If you're just talking about a story-book fictional universe, you can make up whatever rules or mathematics you want about it. We won't stop you. I don't know why you'd randomly pick one book like that. You could use any of them. Noddy goes to the hardware store.

There's a very obvious scientific problem though with just assuming that things that apply to a story, or someone's imagination, also apply to reality. That's why we use evidence.

[The Grand Nudger]

Math isn't a useful predictive tool unless it models reality. That's where most of these "god by way of maths" fail.

[robvalue]

Also, all of this never produces anything of any practical use ever.

It amounts to marvelling at stuff, instead of cracking on and trying to learn what you can about it.

I really don't know what anyone hopes to achieve with any of this, except to reassure themselves.

[Mister Agenda]

You're still arguing that low probability events equal miracles.  No they don't.  Low probability events equal low probability events.  The probability cannot demonstrate that it has a supernatural cause, only evidence of an actual supernatural cause can do that.  Eyewitness accounts to unexplained events, even if held to be reliable, even given certain context, do not show the supernatural.

Click here for a Wikipedia article on Bayesian inference and probability theory.  Probability theory says that you not just assess the probability of an event and make your conclusion, but you must update that probability given any new evidence, information or conditions (timing, context, etc.). 

"The posterior probability of a hypothesis is determined by a combination of the inherent likeliness of a hypothesis (the prior) and the compatibility of the observed evidence with the hypothesis (the likelihood)."

You can run the formula for each hypothesis (H) and compare.Let's do the crippled man:

                    P(E/H) x P(H)
P(H/E) = ------------------------------
                          P(E)

H = Hypothesis, man was healed by Jesus
E = man walks, including timing and context

P(E/H) - probability of E given the hypothesis that Jesus can heal = .90
P(H) - probability that Jesus can heal cripple before E was observed = .01
P(E) - likelihood that E happened without H (call it "natural causes") = .05

             .9 x .01
18% = ----------------
               .05

Bayesian logic also tells us to use what we already know to evaluate the probability of a claim being true and evaluate the quality of evidence that would be sufficient to overcome a claim that contradicts what we already know.

If I say I tied my shoes this morning, you should believe me, or at least not make an argument out of it. You know that shoes exist. You know that shoelaces exist. You know that tying shoes is possible. Lots of people tie shoes. I have nothing to gain by lying about it. You have nothing to lose by believing me.

If I say I resurrected a woman who had been dead for three days this morning, the calculation is completely different, and having an eyewitness doesn't improve it much. We don't know that the woman was really dead. We don't know that bringing someone back from the dead past clinical death is possible. We do know it would involve undoing three days of decomposition, which would be the most complicated task humankind has ever undertaken. We don't know that weird powers that would let someone do this exist or if they are even possible. If I can get people to do this (believe my claim), I have a great future as a cult leader (so I have a lot to gain). If you believe it and it's not true, you've followed a false miracle. We do know that people will lie for attention and we do know people can be delusional.

My claim about resurrecting the dead woman needs a little more than a dude who can vouch for me. before it becomes reasonable to accept it as true

[Cyberman]

It's the same kind of fanwankery that the Vatican used to justify fast tracking that old fraud Mother Teresa into the sainthood; declaring it a miracle that a picture of the old bat cured a woman of a tumour that her husband and her doctors said she didn't have.

In this iteration, we're told that we're starting from two presumptions: that a crippled man was 'healed' (to use loaded language), and that said healing was done by Jesus. In the hypothetical, the observation is that the man can suddenly walk, then the formula is applied to determine the likelihood of that event. The Jesus part we're expected simply to swallow by fiat.

[robvalue]

We assume the story is true, so that we can write down probabilities, to prove that the story is true?

[Mister Agenda]

1) No matter how many time you guys repeat "argument from ignorance", it still won't be so. An argument from ignorance would be me asserting miracles happen because you can't prove they don't. I am not doing that. I am showing that logically, supernatural causes are possible and mathematically can be weighed against an event occurring as a result of natural causes.

2) Some have tried to circumvent the discussion by claiming supernatural causes do not exist--to which I replied is a positive assertion and will have to be proved.

Note the distinction between the two. Furthermore, there is nothing logically wrong with inferring some supernatural entity from evidence of supernatural causation.

1. You are not showing that supernatural causes are possible, you are claiming it. Until something has been proven to be possible, you can't apply Bayesian logic to it. Proving something possible is a necessary step for it to be meaningful to bring probability into it.
2. Pointing out that you have to prove supernatural causes DO exist before you can assign them a probability above zero is perfectly legitimate.

If you had the slightest evidence of supernatural causation, you would still have to prove supernatural entities; by which I presume you mean conscious intelligent beings with intent behind their supernatural interventions. If your evidence of natural causes was sand, you could not then infer people because you've got sand. If people are resurrected by supernatural means, it could just be something supernatural forces do sometimes. Maybe supernatural forces respond to humans with a particular rare blood type. There are steps between 'something supernatural caused something to happen' and 'God'.