So I'd like to get kicking soon on the project of actually presenting the positive evidence for Christianity. In my view the best evidence is the historical testimony of the apostles to Jesus' Resurrection (along with other ancient and modern miracle claims). However, some people have problems with this because it isn't scientific, and they think that only a "scientific" proof of miracles should qualify as evidence.
The idea that Science is the only very reliable way to gather empirical data is called (usually pejoratively) Scientism. It is closely related to Naturalism, the belief that the world consists entirely of a certain class of physical things, of a sort which can be scientifically analyzed. However, the two are not the same, since Scientism is a claim about there being only one good methodology for learning about the world. A Naturalist is free to believe that there are valid nonscientific methods for learning about the world, as long as they also think those methods don't reveal the existence of any entities they'd consider supernatural. (There's a bit of a definition problem in defining what exactly natural vs. supernatural can mean, but we more or less know what kinds of things this sort of person doesn't believe in: gods, miracles, spirits or ghosts of any kind, psychic powers, destiny, reincarnation etc.)
Well, Scientism in its strongest form is obviously stupid, since as I pointed out here there exist several other kinds of evidence-based inquiry that involve different methodologies. Here's another rebuttal by atheistic philosopher Richard Chapell, who points out that Scientism isn't even logically consistent with itself. So, there may or may not be good reasons to believe in religious claims, but "Science" taken by itself is not one of them.
Well, that was easy. Maybe too easy. Because, after all, someone could say this: Even if there are nonscientific methods of inquiry, hasn't Science at least taught us something about the way the world is? And hasn't it taught us something about what kinds of evidence are reliable? Maybe there isn't a sharp contradiction between Science and Religion, but maybe there are things that make it more difficult for a scientifically-minded person to accept religious claims. I think a lot of people have this idea at the back of their heads, and I'm going to try to address it in my future posts.
For further reflections on the relationship between Science, History, Philosophy, and the various arguments for and against Christianity, see here:
It also explains briefly why I think the Historical Argument for Christianity is quite strong, although I plan to go into that in considerably more detail here.
(Erratum: there are a couple things I'd phrase differently if I were re-writing this essay now. First of all, my parenthetical statement about "overcredulous Catholics, Pentecostals, and missionaries to Third World nations" was intended as a statement of a skeptical point of view rather than my own view, although there certainly are some overcredulous people in the groups named. And this book has convinced me that modern day miracles are more frequent than I had previously thought. Also, the phrase "tortured to death" should really be replaced with "tortured or killed"—in fact the whole sentence is too strongly written, and should make clearer who exactly it refers to. For now read it referring to "several of the key eyewitnesses", I guess.)