Did Jesus, meaning "Jesus Christ," centerpiece of the Christian religion, exist or not?
I don't care (and neither should you).
Now, don't get me wrong here, as I'm what we usually would call a "truth-seeker," meaning by that someone that is interested in knowing what is (and was, and will be) true as well as that may be known. I'm also a bit of a polymath, meaning by that that I am interested to the point of seriousness in just about every academic field in the world. So, in that regard, I do care to know whether or not Jesus lived or didn't, but in the regard that I think such information is hardly more than trivia at this point, I don't really care one way or the other. I have no emotional investment in the notion, and I don't think anyone else needs to have any either, at least beyond the normal academic curiosity about a figure that has become, real or otherwise, important historically.
Why don't I care whether or not Jesus existed, besides the fact that it's essentially trivia? Probabilities.
The relevant probability is the likelihood that the Christian religion is true, and from my perspective, the probability that Christianity is true is zero, not least because I think the probability that any sort of non-abstraction god exists at all is zero, almost surely. (Additionally because the Christian God, as depicted, is logically impossible, rendering the probability that it exists as described at exactly zero--although it could technically be possible that some abstract god does exist and the Christians have merely been wrong about it all along, hence the distinction between exactly zero and zero "almost surely" in the two cases here.)
So, since I think the probability that any "real" god exists is zero, almost surely, and because the probability that the god that underlies the Abrahamic religions exists is no larger than that (so zero, almost surely), and because the probability that the Christian story that depends upon it is true is no larger still (so zero, almost surely), I'm pretty content with the thought that it doesn't matter one way or the other if the historical evidence stacks up in favor of "yes, Jesus existed" or "no, Jesus didn't." In short, I don't particularly care because Christianity isn't true either way, and there's no other particularly noteworthy reason to care whether or not Jesus existed. This is just straight mathematics, by the way: a hypothesis that depends upon other hypotheses in order to be true cannot have a probability of validity that is higher than that of the hypotheses upon which it rests.
To clarify this, let me briefly illustrate--if Jesus never existed at all, Christians could (and probably would) simply say that Christianity is based upon a set of philosophies that were attributed to a character that embodied them. Indeed, for the most part, this is what Christians already do and, in all likelihood, have been doing all along. On the other hand, if a historical Jesus really did exist, the probability that he was/is actually God is zero, predicated upon the fact that the probability that the Christian God exists is zero (and the additional hypothesis that this God became man in Jesus, yadda yadda, seems even less plausible still).
Now, this is pretty interesting for me to self-examine because, indeed, I do think it is likely that there was a historical figure of Jesus, and I go further in that I think "he"* is responsible for saying a lot of the things that are attributed to him--or at least rough approximations of those things. I just think that an examination of the probabilities of the situation, again--and even without the probability that God exists being considered--demolish the belief that Jesus was what he might have thought he was.
* I actually think the explanation of Jesus that makes the most sense is not that he was a "he," but rather that he was one member of a group of people (probably all hes, so this isn't some weird gender-bending argument) that was likely to have been amalgamated into a single character in the Gospels. John the Baptist would likely have been part of, if not an early leader, in this group of people who were a group of folks who happened to believe, not unlike many since, that a radical reorganization of the world was nigh at hand and that a particular subscription and seriousness with regard to particular aspects of the contemporary superstitions would ensure importance (or even kingship) of the coming new world order. Indeed, I go further and assert that it is most likely that Jesus was the character created from this movement combined together with many superstitions and legends woven into his character to make the story more powerful and theistic.
The relevant probability about Jesus--without considering whether or not God exists or even whether the Christian dogmas can possibly be true--that I think utterly destroys our ability to take him seriously enough to still be asking these kinds of questions about him 2000 years later was really articulated by C.S. Lewis, everyone's favorite near-miss Christian apologist. Lewis is famous for having said that it was rather certain "proof" of Jesus' claims that he must be either: "liar, Lord, or lunatic," neglecting the obvious fourth alliterative L captured by "legend."
Lewis was on to something there, and he was no slouch on the character we now call Jesus. Liar, in the intentionally dishonest sense, is probably incorrect, as Jesus seemed not to gain from his claims, so that leaves Lord and lunatic. Lord requires some belief in God, because clearly no one is talking about a normal feudal lord--a title Jesus clearly doesn't satisfy anyway, as he owned no lands--so we'll compare it against lunatic made legend.
I'll get Bayesian with this to make it slightly more formal--and my hypothesis will be that Jesus was "Lord." Here, in fact, I can be quite generous to Christians and pretend that for assessing the "prior probability" (see link to one of my previous Bayesian argumentation posts) that Jesus was Lord at roughly 50%--letting liar be dismissively unlikely compared with the choice only between Lord and legendary lunatic. This is a very generous assumption, I hope you can agree, since there haven't been all that many recognized God-men walking around anywhere or ever, and technically a good estimate of the prior here requires an estimate of how likely it is that the underlying God story is true, as it is part of the relevant background knowledge.
That leaves the role of evidence to be considered. This is problematic for Christians. Why? How many people a year claim essentially to be god-incarnate? Rather a lot, actually. Some of them get significant followings (here's a list of notable people who have claimed to be Jesus specifically). Some of them happen to be widely believed to be miracle workers, e.g. Sathya Sai Baba. How many of them do we take at their word, though? Unless we join their cults, zero.
We know more, in fact. Consider the case of Harold Camping, widely considered to either be crazy or fraudulent--probably some of both. Camping got quite a following, involving donations of very large sums of money from devoted followers, sure his predictions about the end of the world would be correct, and his case isn't isolated. In fact, lots and lots of apocalyptic preachers have existed and have gotten very noteworthy--here's a rather long list of some of them. What is most noteworthy about this list is the very large proportion of them within the last few decades--more likely to be an artifact of better record keeping than in increased drive to create them, which is attested to by the general increase in these sorts of predictions corresponding with the writing-rich Renaissance in Europe. We have good reasons, then, to believe that when we were more superstitious, like in the first century, we would have had considerably more people making similar claims. How many of these folks, including Jesus (within a generation, remember), have been right? Zero.
The story of Jesus being rejected as crazy by his family and in his hometown is another huge piece of evidence in favor of "this is the story we'd be hearing if Jesus was actually crazy." Indeed, it's consistent with the kind of crazy people we are actually familiar with, if we do ourselves the favor of putting ourselves in a time when mental illness was an absolute stigma (it's still bad now, but not like before it was partially understood). That this made it into the gospels is a pretty good indication, since it doesn't bolster the "Jesus is God" story that makes up their central thrust, that Jesus might have been a lunatic. Admittedly, the story could have been added as a contrivance to cover up for the fact that early Christians were also regarded as crazy, which can be read in a few different ways that don't need further comment.
What about Jesus' miracles? Since there is no evidence for Jesus' miracles, and his 'miracles' are rather pathetic
in the first place, these aren't helping matters much, and they are the
kind of positive evidence that Christians have to (and do) bank upon to
get their beliefs off the ground. The fact that a number of his purported miracles line up neatly with stories reported to earlier legends--indeed nearly all of them--stacks up pretty heavily against getting to include these into the calculation. Certainly, if Jesus really performed these acts as described, they would constitute significant reason to doubt that the "lunatic made legend" explanation is insufficient, but more certainly, we cannot believe that he actually managed them.
My point over the last few paragraphs is that the evidence we see is very nearly exactly what we should expect to see if the real historical Jesus were an apocalyptic preacher, i.e. a lunatic. This allows us to make the consequent probability (that we would see this evidence on the hypothesis that Jesus is not Lord) very close to one. I think it's rather generous to conclude that there's, at best, a one in a million chance that we're wrong in thinking that the evidence we see can be explained by Jesus simply having been crazy and made into a legend. Why? We have ample evidence of crazy people acting like this (literally in the millions), and some proportion of the most charismatic of them launch religious movements--resulting in lots of religious movements.
Now, on the other hand, how likely is it that we would see what we see if Jesus really were Lord? If he really were Lord, I think it's entirely fair to point out that we probably would have seen a religious movement build up and sweep the globe around his teachings. This is exactly what we see--sort of. There are a few problems. For instance, Jesus supposedly said we would know the truth of his teachings by the unity of his followers. Perhaps I'm crazy, but over 40,000 denominations of Christianity, some which outright call the others heretical, doesn't speak well for this claim. The fact that there had been more than 80 serious heresies (which amounted to full redefinitions of what orthodox Christianity meant) by Augustine's time alone (see C. Freeman, The Closing of the Western Mind) isn't speaking well for it either. That Constantine basically defined Christianity for political purposes starting with the first Nicene Council in 325 isn't either. That Constantine's grandson Constantius II said, "But what I wish, that must be the canon," isn't either. (See C. Freeman, again.) Maybe, then, that there is a widespread religion based upon teachings attributed to Jesus isn't a lot of great evidence for Jesus being Lord, particularly since there are also many other major religions claiming to be The Truth that reject Jesus' claim of being Lord and yet still spawned major religions (including Scientology, which was created nearly openly as a fraud by a famous science fiction writer within the last century).
But it gets worse. Since Jesus reportedly (repeatedly) instructed that we would receive whatever we pray for in faith, however, and since we don't observe that, the likelihood that he knew what he was talking about there is probably not very good. One would expect the Lord not to mess this kind of thing up. That Jesus' reported teachings were in some cases revolutionary, but not particularly so, and since they were all well within the context that an apocalyptic reactionary would be able to concoct in the first century does not help his case. That Jesus fails to account for disease processes accurately, despite his reported ability to cure them, for example, is a strike against him. Indeed, that he supposedly cures a few cases of leprosy but never bothers to teach people to make antibiotics to cure it more widely doesn't speak well for the "Jesus is Lord" claim. As noted, that Jesus is dead wrong about the end of the world that is the real centerpiece of his ministry and the foundational basis of his lectures on morality is a heavy strike against this claim. Indeed, Jesus is even reported to have admitted it on the cross--"My God, my God, why have you forsaken me?" is just not the kind of cry you expect from the Lord, who would have seen that things were going according to plan.
Then there's that not much in the way of reputable historical sources back up Jesus' life. Christians say there are, but not only aren't there many sources out there that would qualify, that number gets smaller and smaller as scholarship on the sources continues. If Jesus were Lord, consistent with the story given in the Gospels about his heralded birth, mystics coming out of the East to meet him there, Herod killing every infant male to do him in, and whatnot, you might think a historian (and there were several) might have taken notice of the kid. You would be right to expect that someone would have bothered to pay attention to him in the roughly 30 years between this allegedly miraculous birth and when he started preaching loudly on street corners--but no one did. Like most crazy people, Jesus was completely ignored until he started yelling in the streets, and then by the Who's Who committees of the day, he was ignored after it started. This isn't what you expect when someone is the Lord.
These things (and others unmentioned--like that on average, Christians fare no better than other people of the world with regard to essentially anything that has to do with chance occurrences or even most preventable problems) come together to look pretty ugly for the probability that the evidence that we have is what we should expect to see if Jesus really was Lord. What number is appropriate? Without accepting the premise that Jesus, as Lord, was simply wrong about a large number of very consequential things (whatever that would imply about this hypothesis), one in a million seems extraordinarily generous. Note that we didn't even touch that this number has to actually be less than the probability that the underlying God even exists, which even if not zero (as I claim) is very, very small for a number of good reasons (like the Problem of Evil--see Richard Carrier give a brief analysis of this at Skepticon 4 in this video). So, I feel very generous in giving a probability of one in a million that the "Jesus is Lord" hypothesis predicts the evidence we actually see in the world.
Putting it together, a prior probability of 50% (insanely generous), and consequents at 0.000 001 and 0.999 999 gives us a posterior probability of only one in a million that Jesus was Lord instead of lunatic made legend. This is, without even having to appeal to whether or not God exists, just short of the same standard of proof that the most rigorous sciences require to say whether or not something has occurred. Thus, even being quite generous (comically generous) and while ignoring the central premise and many, many of the inconsistencies surrounding the story of Jesus, we can conclude that there's essentially no reason to believe he was anything more than a crazy person (technically, I'd go with a "socially conservative, reactionary first century Jew from a minority sect that joined and preached the message of a small apocalyptic-messianic cult.")
(If we throw in the very conservative estimate from that Richard Carrier video that God only has a one in a million chance (maximum) of existing at all, then our prior is dropped to 0.000 000 5, resulting in a posterior likelihood of the claim that Jesus is Lord of only one out of two trillion--about the same likelihood as winning a lottery by choosing to stand in the correct, randomly chosen square foot of the state of Nebraska.)
This brings me back to my central point of this longer-than-expected post: I don't care if Jesus existed or not any more than I care if any other particular crazy person in history existed or not. It certainly wouldn't prove Christianity true if he did exist, as he was with very high likelihood just a crazy person, and if it could be shown that he never existed, Christians would be happy to go on inventing him as they always have, with whatever set of weird contrivances that go along with it--just like they do with God and the Holy Spirit. The entire Jesus story would simply be claimed to have always been intended metaphorically, blah, blah, blah.
Like I said, though, the chances most likely stack up that some "Yeshua" character at the right time, in the right place, doing the right (crazy) things to fit some of the stories did exist and was made out to be more than he was in many way. I don't really care, though, and think it's a tremendous waste that so much otherwise productive time and talent has been dumped into trying to find out and defend it one way or another.
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