Met, Tom. Fleet, all--Bayes anyone?

Discuss either theological doctrines, ideas about God, or Biblical criticism. I don't want any debates about creation vs evolution.

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Re: Met, Tom. Fleet, all--Bayes anyone?

Post by QuantumTroll » Tue Oct 27, 2015 7:41 am

I have no stake in Jesus' existence or non-existence. The story of Jesus exists and impacts the world today, and that's far more important and interesting to me than one (pretty cool) dude two thousand years ago. So in the interest of testing the applicability of using Bayesian inference to determine Jesus' historical existence, I'll have a go.

P(H) — What's the inherent probability of a revolutionary Semitic Jew named Jesus having existed in the first century AD? Well, Jews did live under Roman rule in that area in that time, and there was friction between the Roman rulers and the Jews during the first half of the first century that eventually escalated into war. The name Jesus was relatively common, archaeologists have unearthed at least 71 contemporary tombs bearing that name, and shows up in old scripts many times, so a revolutionary Jew named Jesus is certainly not a ridiculous proposition on the face of things, but I can't find the crucial datum of how many non-Jesus tombs and names there are, nor how many revolutionary Jewish leaders there were. But suppose they've discovered 500 tombs in total, and suppose there were 10 leaders, then P(H) ≈1-(1-71/500)^10=78%.

P(E) — It's far more difficult to estimate the probability of the model evidence. The Middle East is a dry place and written evidence on clay tablets and parchment had a better chance of surviving there than, for example, Viking materials in rainy Norway and Iceland. The Middle East is also well-studied by archaeologists, so the evidence that does exist has a good chance of coming to light. Moreover, the Romans were avid record-keepers and historians, producing lots of potential evidence. All this summed together means that P(E) must be quite high, but it's hard to put a number to it. If we flip it around, however, and ask what is P(~E), it feels like the odds of not having any evidence survive is very very low, maybe 1/20 important political figures are missing from the records, so I'm setting P(~E)≈5%. Suppose there were 100 important figures, what are the odds all of them are there? P(E)= 35.8% I admit that I may not understand this variable well enough.

P(E|H) — What is the probability of finding evidence of Jesus given the existence of Jesus? Well, in the above paragraph I suggested that 1/20 important figures might be missing, so let's go with that. Given H, we know that one figure is not missing, but the odds are the same for the rest. This gives us P(E|H)≈37.7%.

That gives us: P(H|E)=37.7%/35.8% * 78% ≈ 82%.

This is interesting. 1/5 chance of you being wrong if you believe in a real Jesus. Not something to bet your mortgage on, but not bad.

What's interesting mathematically is that the power of the update comes entirely from my guess that 1/20 important political figures are missing from the records. If the records are worse, then the odds of Jesus being real goes up. If the records are better, then the odds of Jesus being real goes down. Oddly enough, this gives believers an incentive to destroy information about Roman Judea (in the sense that they'll be "more right"), and it gives mythers an incentive to dig up all available information about political persons in the 1st century Middle East (because then they'll be "less wrong").

The bottom line is still that the estimate of the prior probability is of fundamental importance. And in the case of historical Jesus, the circumstances were appropriate for such a man to exist, so he probably did. The Bayesian update is only an update to this fundamental number and doesn't greatly affect the outcome of the analysis.

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Re: Met, Tom. Fleet, all--Bayes anyone?

Post by met » Wed Oct 28, 2015 10:56 am

Nice demo, thx QT
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Re: Met, Tom. Fleet, all--Bayes anyone?

Post by Metacrock » Thu Oct 29, 2015 3:41 pm

probability of Messianic candidate from that era is pretty high too. But the whole issue is that Bayes does not offer a methodology or data. It depends entirely upon already having data and upon your assumptions. I also think there's a difference in probability of past events an d future. Carrier assumes he can treat past events like future events I don't think so.

Future events might be likely or unlikely but past events are a done deal. wired things happen and event we th8nk unlikely happen.
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Re: Met, Tom. Fleet, all--Bayes anyone?

Post by met » Thu Oct 29, 2015 9:12 pm

you touched on an idea, which Rubenstein also touches on, and I've muddled with for awhile too, that the scientific outlook is founded on a (sometimes unfounded) assumption of 'universal/multi-versal sameness' - ie 'everything is the same everywhere & nothing out of the ordinary happens'. Which - if i were to deconstruct it a la Malabo's deconstructions of neuroscience - I might attribute to its bourgeois roots. 'Nothing much happens' is a good socioeconomic result for the elites and their closest allies, or a fine alternative (for them) to 'the masses rise up and kill us,' at least. In general, those with power prefer mundane predictability. :)

But, staying on topic (to avoid having any more embarrassing threads started just for me :oops: ) I'd also like to point out that 'Jesus never existed' doesn't seem a well-defined topic in the first place. Jesus,as we know him, could have come from a compendium of stories. He could have been a composite figure made of anecdotes from a number of messianic figures from around that period. But the stories had to come from somewhere, and there also might have been one central personality at some point, whose career was later, well, somewhat embellished by other figures' anecdotes or just plain made-up stories. However, if so, how much embellishment could there be before one would be forced say " but that guy wasn't really Jesus." It's like, "which sayings are really from "Jesus" - the Jesus seminar thing - and it seems a grey historical area?

But perhaps Meta can elucidate here....
The “One” is the space of the “world” of the tick, but also the “pinch” of the lobster, or that rendezvous in person to confirm online pictures (with a new lover or an old God). This is the machinery operative...as “onto-theology."
Dr Ward Blanton

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Re: Met, Tom. Fleet, all--Bayes anyone?

Post by Metacrock » Fri Oct 30, 2015 11:25 am

met wrote:you touched on an idea, which Rubenstein also touches on, and I've muddled with for awhile too, that the scientific outlook is founded on a (sometimes unfounded) assumption of 'universal/multi-versal sameness' - ie 'everything is the same everywhere & nothing out of the ordinary happens'. Which - if i were to deconstruct it a la Malabo's deconstructions of neuroscience - I might attribute to its bourgeois roots. 'Nothing much happens' is a good socioeconomic result for the elites and their closest allies, or a fine alternative (for them) to 'the masses rise up and kill us,' at least. In general, those with power prefer mundane predictability. :)

But, staying on topic (to avoid having any more embarrassing threads started just for me :oops: ) I'd also like to point out that 'Jesus never existed' doesn't seem a well-defined topic in the first place. Jesus,as we know him, could have come from a compendium of stories. He could have been a composite figure made of anecdotes from a number of messianic figures from around that period. But the stories had to come from somewhere, and there also might have been one central personality at some point, whose career was later, well, somewhat embellished by other figures' anecdotes or just plain made-up stories. However, if so, how much embellishment could there be before one would be forced say " but that guy wasn't really Jesus." It's like, "which sayings are really from "Jesus" - the Jesus seminar thing - and it seems a grey historical area?

But perhaps Meta can elucidate here....
There is a real web of historicity from writers we have to eye witnesses to Jesus. Paul knew Peter, James, he did meet them. they are in the story for a reason. They mythers want us to think they had a mllon guys named James all were in charge and non e were Jesus' brother.
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Re: Met, Tom. Fleet, all--Bayes anyone?

Post by met » Sat Oct 31, 2015 11:57 am

If there was a guy named James, who was the brother of a messianic leader named "Jesus" (ie Yahua, a common name) does that really prove "Jesus existed?" It all depends on the essential aspects of whom you think Jesus was, and that's subjective. Likely, some fundamentalists would believe, if there's any jot or tittle of the accounts in the NT that are wrong, then, yes, "Jesus never existed."

It's a shock phrase.....
The “One” is the space of the “world” of the tick, but also the “pinch” of the lobster, or that rendezvous in person to confirm online pictures (with a new lover or an old God). This is the machinery operative...as “onto-theology."
Dr Ward Blanton

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Re: Met, Tom. Fleet, all--Bayes anyone?

Post by Metacrock » Mon Nov 02, 2015 9:24 am

met wrote:If there was a guy named James, who was the brother of a messianic leader named "Jesus" (ie Yahua, a common name) does that really prove "Jesus existed?" It all depends on the essential aspects of whom you think Jesus was, and that's subjective. Likely, some fundamentalists would believe, if there's any jot or tittle of the accounts in the NT that are wrong, then, yes, "Jesus never existed."

It's a shock phrase.....
what you say is true in principle but I think there's ton of reasons to think there was a real guy brother named James, claimed to be Messiah, came from Nazareth. there's a lot we don't know. that stuff ant it.
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