It seems to me that there must be single standard in this skepticism regarding the historicity of famous persons from antiquity. None must 'scape whipping--if that is one's program.
Yet because of the halo effect that surrounds the icons of classical antiquity their historicity is normally given the benefit of the doubt. (Homer, Hercules and so forth are another story--and have generally been recognized as such.) Momigliano mentions an 18th-century French skeptic who thought that only four surviving classical texts were authentic. After all, the MS that he knew were all later ones. In the long-run such terrible-simplificateur arguments (which are at least consistent) do not gain much traction. One can take any set of premises and push them to an extreme that seems convincing to the pusher, but to few others. (In another sphere Noam Chomsky is a contemporary example.)
I am inclined to think that the special pleading that is found in Price and other "Jesus did not exist" scholars is in part the product of their early personal history. Price was brought up as an evangelical, became a pastor, and then lost his faith. In some ways Warren never ceased to be a Jew, incorporating elements of their anti-Christian polemics. I remember how he used to chortle over the Toledoth Jesu, a scurrilous late-medieval text in which (if memory serves) the devil sodomizes Jesus.
What's sauce for the goose is sauce for the gander. I do not find that the Jesus-didn't-exist school are prepared to adhere to this relevant bit of folk wisdom. For this reason, their arguments do not carry much weight. Reading Price's book shows this.
The idea that Paul founded Christianity is now the conventional wisdom. Yet like so much of what we thought we knew about that era, this truism may not be correct.
Btw, I think that what you said about the Nestorians would better apply to the Arians.
[Revised ending]. "By modern standards, few figures from Greco-Roman antiquity are well documented. For most ancient philosophers, for example, we have (to all intents and purposes) only the data recorded by Diogenes Laertius. Yet few doubt that Heraclitus or Democritus actually lived. In her book "Lives of the Greek Poets" (1981), Mary Lefkowitz points out that "virtually all the material in the lives is fiction."
Why then do we not say that most of the ancient Greek philosophers and poets never existed? The information we have is exiguous at best. The reason is that there is no evident motive for such doubt--no "cash value" in William James' cynical phrase--even though they are less well attested than Jesus.
Doubt is deployed as a weapon. An example demonstrates this rule. The Greek archaic poet Sappho has become an icon for modern feminists--a sort of Sappho Christa. Perhaps for this reason, some scholars have begun to doubt whether she existed.
The problem with sorting out the facts, however uncertain they may be, concerning the life of Jesus stems from the situation that we have too many sources, not too few. In addition to the four canonical gospels, the texts of at least 16 others are known. There is other data in the Acts of the Apostles and the Epistles, not to mention such early writers as Marcion, Clement of Alexandria, and Irenaeus of Lyon. The situation is closer to that of Socrates and Alexander, well attested but with numerous contradictions, than it is to that of Heraclitus and Anacreon. I am inclined to think that the position that Jesus did not exist is ideological. It is based on special pleading--a one-sided presentation of the evidence that highlights every contradiction and dubious assertion, refusing to countenance any other evidence.
When all is said and done, Jesus probably did exist--not the divine Jesus of the fictitious “Holy Trinity,” but the relatively modest teacher admired by Thomas Jefferson."