mountainman

“Bayes’ Theorem for Beginners: Formal Logic and Its Relevance to Historical Method — Adjunct Materials and Tutorial”

In this example Carrier is happy enough to discuss the logical consequences of the historical existence of Julius Caesar - namely his shaving. The historical existence of Julius Caesar is here implicity (not explicitly) taken to be true.

I think we can expect that Carrier will directly address the historical existence of various identities related to the history of christian origins, such as Jesus and Paul and Papias and Hegesipus and Pilate etc. However it is entirely reasonable to expect that Carrier will not necessarily running with an implicit hypotheses that these people all existed like Julius Caesar above.

It is likely that an explicit and antithetical hypotheses may be explored - that "X was not a genuine historical figure".

J-D

Carrier (rightly) does not say 'given the historical existence of Julius Caesar, it is likely that Julius Caesar shaved at least once a week'; he says 'given everything we know about Julius Caesar and Roman aristocratic customs of the time and human male physiology, it is likely that Julius Caesar shaved at least once a week'. In terms of the general model he is using, 'everything we know about Julius Caesar and Roman aristocratic customs of the time and human male physiology' is an example of what he calls 'background knowledge'. In his Bayesian equation, this is symbolised by the letter b, which he defines as 'total background knowledge (all available personal and human knowledge about anything and everything, from physics to history)', of which, by definition, 'everything we know about Julius Caesar and Roman aristocratic customs of the time and human male physiology'. The background knowledge is emphatically not the same thing as the 'hypothesis being tested', which in Carrier's Bayesian equation is symbolised by h, and which in the example at hand he explicitly states to be 'Julius Caesar shaved during the week before he was assassinated'. If you want to follow Carrier's example, you will need to do what has so far been beyond you and state clearly what the relevant 'background knowledge' is, what (distinct from the 'background knowledge') the hypothesis being tested is, and what (distinct from both) makes up the third term in Carrier's Bayesian equation, e, defined as 'all the evidence directly relevant to the truth of h'.

mountainman

This background knowledge can be enumerated and obviously must include a fundamental implicit postulate that the subject of the hypothesis, Julius Caesar, existed in history.



Where have I suggested that they are the same thing?


Carrier's future example appears to be the discussion of the historicity of Jesus. The historical existence of Jesus is NOT NECESSARILY one element in the background knowledge (all available personal and human knowledge about anything and everything, from physics to history)', of which, by definition, 'everything we know about Jesus - including his possible mention in manuscripts). If I wanted to follow Carrier's example, I would question the historical existence of Jesus by testing the truth (or otherwise) of the hypothesis "Jesus was an historical figure".

The historical existence of Jesus is not necessarily implied from the background knowledge about Jesus, whereas the historical existence of Julius Caesar is a postulate held to be true and factual on the basis of the background knowledge, including the coins and texts, of Julius Caesar.




The assumption of the historicity (or otherwise) of Jesus (and/or Paul) remain hypotheses yet to survive proper peer review, as I have been consistently arguing in this thread against those who think they know otherwise.

PS: Carrier has moved his blog from an old address to a new address

J-D

No, that is not obvious. It is not obvious what meaning, if any, such a statement would have.Implicitly.When stated in that form, the meaning of the hypothesis is not clear enough for it to be testable, for reasons already explained.No: if it's held to be true on the basis of background knowledge then, by definition, it is not a postulate.And in this same thread I have repeatedly and in detail explained how neither 'Jesus never actually existed as a historical person' nor 'the historicity (or otherwise) of Jesus (and/or Paul)' nor any of the similar formulations you have come up with is a sufficiently clearly expressed hypothesis for meaningful discussion (or testing) to be possible. It isn't when you say it, and it isn't when Carrier or anybody else says it. Greater clarity is the indispensably necessary first step.

mountainman

Your responses in this discussion to date seem to indicate that you think you clearly know better than Herman Detering, Earl Doherty and now - Richard Carrier or anybody else - put together. Is this true?

J-D

I didn't say anything in general about Herman Detering, Earl Doherty, or Richard Carrier. I commented on some particular statements you attributed to them which were not sufficiently clearly expressed for the purposes of this discussion. The clarity (and other merits) of those statements are not affected one way or the other by who made them.

As it happens, since you bring the subject up, some of the other statements you quoted from Richard Carrier were admirably clear and useful. I give him credit for the statements. I don't give the statements credit for coming from him. (I might add that some of them were still not clear enough to prevent you from misunderstanding them.)

Nobody has a perfect record of success in achieving clarity of expression. Not Herman Detering, Earl Doherty, or Richard Carrier; not me; not you. Each statement needs to be taken on its own merits--or lack of them.

mountainman

It seems clear enough that Carrier treats the historicity of Jesus as an hypothesis h to be evaluated. Competing hypotheses would include ~h etc. Leaving aside for the moment the Bayesian expression representing the probability that a hypothesis (h) is true given all the available evidence (e) and all our background knowledge (b), it is clear that the historicity (or otherwise) of Jesus is hypothetical.

The clear expression of this hypothesis h may be as simple as "Jesus was an historical person" or even "Jesus existed". The antithetical hypothesis ~h, which Carrier seems to be exploring is "Jesus never actually existed as a historical person" (taken from WIKI on Carrier).

It also follows that if the historical existence of Jesus may be treated as an hypothesis, so may the existence of Paul.

J-D

The statements 'Jesus was a historical person', 'Jesus existed', and 'Jesus never actually existed as a historical person' are not sufficiently clearly defined to be testable hypotheses, for reasons I have already outlined. Carrier may think they are or he may not, I don't know; what I know is that if he does think so, he's making a mistake. If you think so, you are making a mistake. Anybody who thinks so is making a mistake. The mistake is the same mistake independently of who makes it.

mountainman

Was Bilbo Baggins an historical person?

J-D

Bilbo Baggins is on Google+, and on Twitter: does that count? Why or why not?