According to who? Many people. I can recommend to you some eminent Christian scholars like N.T. Wright (who I think I mentioned earlier), James White, William Lane Craig, and others. But it makes sense that the Gospels were written by Matthew, Mark, Luke, and John. The usual counterargument is we don’t know who wrote them, we don’t have the originals (only copies of copies), and the authorship was only attributed much later. First off, it doesn’t matter we don’t have the originals. All the copies we have of the Gospel accounts are so incredibly similar, with only slight, insignificant deviations, we can be very sure that the copies we have are faithful to the original. First, if Luke and Mark were only later attributed as the authors of the Gospels, we have to answer an important question: why? They were relatively minor figures, why wouldn’t the Church fathers who supposedly forged the Gospels pick someone more famous and important to “author” the Gospels? Secondly, there was widespread support among the early Church fathers that the Gospels were written by their attributed authors. Thirdly, as regarding John:

What verse? John 21:20-25: “Peter turned and saw the disciple whom Jesus loved following them, the one who also had leaned back against him during the supper…. This is the disciple who is bearing witness about these things, and who has written these things, and we know that his testimony is true.” The “disciple whom Jesus loved” is widely agreed to be John. Early Church tradition is also unanimous on this. This page goes into it in much more detail: http://www.gotquestions.org/disciple-whom-Jesus-loved.html Sure, it's plausible. But that doesn't mean their is good reason to believe. Again: why should we believe that Hannibal and Alexander existed? The accounts about them were written hundreds of years after they supposedly lived. They could simply be myths, or their achievements could be all made up.

Scholars have proposed a range of dates from as early as 60 AD to as late as 90 AD. To be honest I don’t buy what many scholars say, unfortunately many people who go into seminary seem to go there with the express prejudgment that the Bible is wrong and they do their damndest to prove it. Some scholars also say the world is 6,000 years old and that evolution doesn’t exist. Are they right? Again, it is erroneous to think the Bible was written as late as 90 AD, for several reasons. 1. There are no legendary distortions in the Biblical texts, they are written as if someone was near Jesus and simply recording events. 2. The Second Temple was destroyed in 70 AD. In the Gospels Jesus predicts its destruction. If the Gospels were written after 70 AD, why didn’t they say “Aha! See, we told you! Jesus predicted it, and it really happened! 3. Again, if the Gospels were written after 52 AD, the date of Paul’s death, why didn’t they mention it? Which brings me to my next point: It quite easily could have been the case that Paul's death was just left out. That would be like me writing a biography of JFK and ending it with: “and then Kennedy went to Dallas in a motorcade. The end.” Why wouldn’t they mention such a momentous occasion, the death of one of the founders of the Church and someone who wrote half the New Testament? And that in no way makes it a good reason to believe. How so? It doesn’t make sense that people who lived closer to his life are more reliable eyewitnesses?
The number of people who believe something has no bearing on whether or not that something is true. So we should no longer say “a majority of scientists agree that evolution is true and that climate change is real”? As demonstrated through the alien abduction example, it doesn't matter that it is embarrassing. The criterion of embarrassment is something used by historians in general, not just Christians, this is a widely accepted historical technique (this methodology is also used by skeptics like Bart Ehrman who is an atheist).
Yeah, that doesn't make them contradictory. What makes them contradictory is that Mark says that only a man was at the tomb, Matthew says that it was Jesus and an angel. Luke says that it was two guys. And John says that there were two angels and Jesus. That’s not contradictory. There were two angels. Some of the writers only mention one of them, some of the writers refer to them as men. There’s no contradiction here. If he said there was ONLY one man, then yes, it would be a contradiction. This happens in history too: Livy and Polibyus both discuss the Punic Wars, but they vary in tiny details. They are our two main primary sources from the ancient world about the Punic Wars, and no one would seriously doubt the prime essence of what they say.
First of all, I never said that miracles are impossible. Second of all, define miracle. Really? Then why do you claim it’s ridiculous to believe that God came to earth, and therefore any other explanation is possible, including that a group of Jews went against all their traditions, had a mass hallucination, and decided to suffer torture and death for that mass hallucination?
Also: “a surprising and welcome event that is not explicable by natural or scientific laws and is therefore considered to be the work of a divine agency. “ Really? It makes more sense to you that a god that nobody seems to understand impregnated a virgin, a virgin who gave birth to god himself, who then went on to die to make a loophole in rules that he himself control? That makes sense? See above. Also, it’s not a “loophole,” theologically speaking. God, in Christian doctrine, is infinitely loving, but he is also infinitely just. He can’t just ignore humanity’s sin, but He loves humanity, which is why he dies to save us. That’s the whole gist of Christianity.
Again, people are frequently mistaken. Well, you could use that statement to justify anything.
Again, he could be mistaken. And no, people still do say things that go against what is true. Him saying that has no bearing on whether or not those events are true. There are people today who would say the same thing, "Go out to my brotheren and find that they really were abducted". The difference is, if someone today says “My friend was abducted and there were 500 witnesses, go and ask each one of them, here are their addresses and names,” then I could go to those 500 witnesses and easily show that person lied. There was literally no reason for Paul to encourage people to go out and ask those 500 witnesses to the Resurrection, unless he, for some reason, purposefully wanted to screw himself over and undermine his own religious statements.

You're forgetting that Tom, Dick, and Harry could also be fooled or mistaken. Yes but if you multiply Tom, Dick, and Harry by over 100 then you have a whole lot more witnesses who supposedly saw him. And if I’m the only one who supposedly saw the Unicorn I’d have literally no incentive to tell you “go and listen to these people’s testimonies” because my lie would quickly come to light. Unless I’m some sort of masochist who tells lies and then undermines his own lies.
Just how long do you think he was around after the resurrection? Enough time to eat, drink, and lengthily converse with the Apostles, i.e.: not just around for a couple of seconds. The bible says all sorts of things. It makes sense that they spent time with him and that’s what made them think he was Resurrected. It makes little sense that they saw Jesus die horrifically, were traumatized by it, and then said “Hey! Guess what, I saw a guy who vaguely looked like Jesus for 1 whole minute, He’s back guys!” This would go against the trend of Messianic movements. There were many Messianic movements before this, as I’ve said above. Why would the movement either 1. Die with Jesus, or 2. Move unto his brother James as the “Messiah?” I am not asking you to say what you think makes sense. I am asking you to support your claim. I am supporting my claim, legends usually pop up long after a person’s death. It’s easier to make stuff up about a person long dead, after all eyewitnesses have gone, than about a person who was recently alive. If I write a history about Reagan that says he shot lasers out of his eyes and could fly like Superman, there are still a lot of people alive today who remember Reagan that would say I’m a liar.
Christianity also has had a huge head start. So has Judaism, Islam, Buddhism, and animism, but Christianity is still the dominant world religion.
Not quite. They start off by posing as a self help type establishment. From there they steadily apply more and more gas, up until the point that you find yourself suddenly paying thousands of dollars for something that has slowly grown on you. Still not the same as Christianity, namely because I doubt the founders of Scientology would have been willing to die and be persecuted for a false religion that they invented.