I was debating a well informed Christian apologist the other day. He asserted that the bible has more bibliographic support than any other ancient works, including Tacitus' Annals and other histories. He stated that the Bible ought to be given historical weight because there are far more manuscripts in existence for the Gospels and they are closer to the time period discussed than the earliest known copy of the Annals.
Much of what he said was correct. There is a several hundred year gap in between the earlist extant copy of Tacitus' Annals and the period in which the original was written. For many biblical books, there are copies still in existence that are 100 or 200 years younger than the original would have been. Having read books by Bart Ehrman detailing the copying process and the inherint human error in biblical manuscripts, I cannot help but apply the same logic to other ancient works that are relied upon for an understanding of the ancient world.
This brings up the question, if Tacitus' Annals and other works could have been altered or embellished to varying degrees from the original, what do we really know about the ancient past? How have historians been able to corraborate the word of historians like Herodotus or Tacitus. I am aware of the doctrine of using multiple sources and archeological evidence when available to come closest to the historical truth. Maybe some of the more educated academics on this site could help me out with this. Interestingly, an apologist would probably say that the different gospels serve as corraborating sources because they were written by separate authors.
How would one refute or combat the apologetic claims made? And more importantly, through what methods did scholarship come to trust certain historical works (such as Tacitus) and cast doubt on the historical accuracy of others (The Gospels).