Let's move all the content on the Testimonium to the it's own page - and leave this page as just a bio of Flavius, with a link to the Testimonium. - Sans Deity 02:07, 22 September 2006 (CDT)
An average life expectancy of 25 years does not mean you've had two "back to back" generations, so to say. It's not true that everyone who witnessed the event of AD 25 is dead by AD 50, and that by AD 75 it's only their grandchildren repeating a now third-hand story. That's just not how it works.
The average life expectancy of 25 was largely due to youth mortality. According to that U of T chart, 35% of people died before 15; if you made it to 15, your average life expectancy was 52.
But that's not the end of it, either. 10% of people make it past 60, and 2% make it past 70. Half of those make it as far as 76.
The potential for eyewitnesses isn't the problem.
The problem is that there were none...
Of the supposed thousands who witnessed Jesus' miracles, who followed him around the countryside being fed by magic fish, who heard the Sermon with their own ears, there ought to been plenty who could related their story to Josephus (or other historians). There ought to have been at least a few who wrote it down themselves, at least a handful of others interested in the phenomenon, if not the stories themselves. Josephus could have been told direct eyewitness stories in his 20's and 30's, perhaps even as he was collecting notes for his book. He could have heard them by people who saw firsthand the miraculous events. He could have had word-for-word stories from eyewitnesses. Even if they were taken as purely fictional, someone ought to have wrote "a lot of people believe this crap. Here are the names of a few of the popular ones."
But he didn't, and neither did anyone else. The only ones who wrote down what they "saw" were the apostles (and that's up for debate) and other church leaders, apparently. How convenient.