Is Christianity based on older myths?

[Mudhammam]

Some assumptions have to be made for discussion purposes.

No, they don't. But okay, let's make them anyway.

If you want to argue that these things are not so, that's fine but I am going with the people who make this their life's work.

So, you should have in view about a dozen completely different conceptions of Jesus. Those are just the ones taken seriously.

A. Scholars believe Jesus existed.
B. Scholars believe the Pauline epistles to be written in the 50s and the 4 gospels between 60-100.
C. There are at least 8 different authors of 27 separate documents. Don't make the mistake of combining them all into one book. They are not.

Okay. So, this is relevant to what exactly?

Okay, to sum up whether Christianity is based on myths, I am hearing the following reasoning:

1. The gospels are not accurate or are complete fiction
2. Paul, Peter, John, and James had motives other than truth to write their letters
3. Therefore the narrative is fiction and the source must be recycled myths.

No, see, "Therefore" implies that 3) is derived from 1) and 2), which makes little sense since 3) is just a recapitulation of 1), and 2) assumes we have writings from anyone named John, Peter, and James. Also, you forgot to add the following premises:
P1. Many religions/cults predate Christianity and contain the exact same language and themes.
P2. The claims made in the Gospels lack corroboration from other contemporary sources, more startling than might be typically expected given the nature of the supposed events.

First, why would we not assume the 8 separate writers believed what they wrote until we have evidence or a plausible motive for a significant conspiracy?

We can assume all the writers, whomever they were, believed what they were writing and were not involved in a conspiracy. Moot point.

Do we assign this type of scrutiny to other historical documents?

Yes. Of course, unless you're so gullible to believe every mythical story ever written.

Can you give me an example of even a group of 5 historical documents that are attesting to something that are all thought to be intentionally false?

Red herring.

Or is it that you think that a plausible motive for this level of falsehood and conspiracy was to start a new belief system based on self-sacrifice, love, and humility in a political climate that was hostile to it?

Like the other 4,000+ other religions currently in existence, those may be some of the possible reasons. Christianity created a community or brotherhood amongst the poor and disenfranchised and empowered those who were politically weak by turning things on their head (as in, it is the poor, the sick, the dumb, etc., that God blesses and stores treasures in heaven for, not the rich or those who keep the law like the Pharisaic righteous, etc.)

Lastly, the conclusion 3 does not follow from the premises 1 and 2. To get to this conclusion, you would have to insert and prove probability of the premise that the early church conspirators had access to extinct and eastern religious characters, stories, and philosophies. I would argue that if premise 1 and 2 are true, it is far more probable that any similarity to myths is coincidence.

Red herring.

I'm starting to think, based on your other posts, that to continue this discussion would be a waste of time because you are either 1) not bright enough to consider the evidence or 2) intellectually dishonest. I really hope your future comments prove me wrong.