Has this man ever existed at all? Outside of the gospels the evidence is very scant.
Not really scant - embarrassingly rich in comparison to other comparable 1st century Judean figures. This tells us that he very quickly became the centre of a major cult, and was therefore deemed of interest, as so many references survive - not a single contemporary one, but that is perfectly normal for the period.
Then you have to consider that never in the history of this planet has a true miracle ever happened or is likely to, even if civilization lasts for millions of years. The laws of physics cannot ever be broken.
How do you know these two claims to be true? Because no one i know in the philosophy of science would believe either could ever be verified? I can see why you might believe them to be true, but they can not be demonstrated - they are
a priori beliefs. This is where my scepticism immediately starts alarm bells ringing. I don't think we can know either of these facts to be true. In my OP I cited David Hume, but here have a look -
http://en.wikipedia.org/wiki/David_Hume#Induction
http://en.wikipedia.org/wiki/Problem_of_induction
It's why in the opening post I was so careful to note this problem - we can not actually just dismiss a supernatural event on these grounds. We are prone to because the scientific method presupposes as an axiom
methodological naturalism, so we take it as being somehow "true". It is not necessarily so however - it is merely a tool for conducting legitimate science.
We often confuse our methodological assumption ("nothing supernatural happens, natural laws always apply" with a truth claim about the nature of ultimate reality.) This distinction is one I think sceptics would do well to understand - science predicates certain things, such as a lack of supernatural events, because otherwise one can not do science. ("Yes, last week, the apple fell because of Newtonian gravity and normal physics; but today it was invisible goblins did it") Those who have adopted materialism as a belief system and abandoned zeteticism and agnosticism often get outraged when I say it, but we ar just confusing the map and the territory here. It may well be (and common sense seems to suggest) that these things are true, and goblins did not do it. But we can't know that. So a sceptical position, as exemplified by David Hume, admits the epistemological limitations - we can't know. Incidentally, Hume gives us teh basis for "extraordinary claims" and "correlation not necessarily equal causation" in the same essay, still worth reading -
http://18th.eserver.org/hume-enquiry.html
http://en.wikipedia.org/wiki/Methodological_naturalism
http://en.wikipedia.org/wiki/Naturalized_epistemology
http://plato.stanford.edu/entries/naturalism/
Thirdly, had this man been resurrected, every historian of that time would have written about it. The ones who wrote about it decades later were writing hearsay. Even without the benefit of modern communications, such an event would have swept the Roman world. We would have libraries full of the account, hundreds of independent sources.
No, we wouldn't. Look up say Theudas, John of Gamala, The Egyptian etc, etc. Messianic claimants who actually did some damage, and really upset Rome, and caused major civic disturbance. What sources do we have for them? How contemporary? Or say Boudicca/Boadiciea? These were people who made a major pragmatic political and economic impact upon Rome. When are the sources? How many survive?

The historiographical issues concerning 1st century texts are nothing like those for say Medieval Europe or the Modern Era.Contemporary attestation is extremely rare for the vast majority of historical figures.
And even in the modern era paranormal claims are barely regarded; try to find attestations in print or on the web for the purported miracles of cult leaders, or supernatural claims. How many historians mention the alleged Miracle of Fatima? I'm guessing very, very few? Zeitoun? Medugorje? How much can you find in mainstream sources like the news media or history books on the levitations of Daniel Dunglas Hume? Or the purported physical mediumship of the circle at Scole, Norfolk in the 1990's?
On the JREF you will find detailed discussion I'm sure of all of the above. Maybe you can find something about the gentleman borne to heaven by doves, or the Angels of Mons. But in a period when religious and miraculous claims were probably far more common and culturally entrenched, I doubt any self respecting author gave this "pernicious superstition" much notice?
So try to look for dates and reference to Honi the Circle Drawer. To understand these things, you always need before claiming paucity of evidence to check exactly what the standards are for the period in question. I fully understand your scepticism, but you need some kind of benchmark?
Here are the classic examples of sources for the most famous 1st century figures, from me on an earlier thread --
Julius Caesar
autobiographical - two sources -
De Bello Gallico; De Bello Civili
Cicero's speeches - including at least three on the subject of Caesar - contemporary
Plutarch - written in 75CE, so +129 years
Suetonius - The Twelve Caesars, written in 121CE, so +165 years
Appian, Roman History - written in 165CE so +205 years
Cassius Dio, writing in 229CE, so +273 years
There are probably MANY more, but these are the standard biographical sources. Any classicist help me out here? The difference with Julius Caesar is of course we also have huge amounts of archaeological evidence, coins, busts, inscriptions. The guy was Emperor. However take a look at the dates of those sources! I would imagine as I say many others do exist, but references rather than biographical.
Augustus Caesar (Octavian)
autobiographical -
Res Gestae Divi Augusti
letter form Augustus -
Epistula ad Gaium filium
Nicholas of Damascus -
Life of Augustus c.14AD, the year of Augustus Death -contemporary
Virgil - contemporary poet, Augustus outlives him. He dies at Brindisium about 15 BCE as I recall -contemporary
Tacitus Annals, which begins with death of Augustus, written in 117, so +161 years
Suetonius - The Twelve Caesars, written in 121CE, so +165 years
Appian, Roman History - written in 165CE so +205 years
Cassius Dio, writing in 229CE, so +273 years
All we have in reality is a very dubious account in a one book written by superstitious people who lived in the first century, the N/T.
And the 1st century Church Fathers, and then the following texts
http://jerome23.wordpress.com/2009/...ed-the-historical-sources-for-jesus-part-one/
and more I have not covered yet... (from my blog)
It's good to be cautious. But again,
I fear you read the Bible as a single book, through the eyes of the Christian faith community - an odd approach for a non-Christian, and one that even I as a Christian put aside when trying to do historical work. Try regarding it as a historian,, as a collection of disparate texts, different sources, that were collected together later...
Hope these vague thoughts help, and sorry for the rushed reply - working at moment...
cj x