Today, August 15, is the feast day commemorating the Assumption of the Mother of God, the Blessed Virgin Mary. This is an important day not only for Catholics, but also for the Eastern Orthodox, the Armenians, Jacobites, Copts, Anglo-Catholics, and anyone who was a fan of "The Secret Life of Bees." Since my spiritual persuasion is Anglo-Catholic it's important to me too. I would be at church today if my car was working, but it isn't, so I'm not.
A lot of people, no doubt, find it hard to believe that the Assumption happened. But I don't share that skepticism. Obviously it's impossible, given what we know about the biological facts of death. A human body is necessarily destined to die- that's just the way we are set up. We age and die, even if we are spared the ravages of sickness or accidents. But that's the whole point- it's a miracle! It's precisely one of the things that makes this so important to the religion, and Mary such a unique figure- that what happened to her never happens to people, in our experience. If people being corporeally assumed into heaven without dying was a normal occurence, then we wouldn't have a feast day to commemorate it.
As for the believability of the event, as soon as you accept the existence of a supernatural, of the existence of God, of the devil, of spiritual powers good and evil, you're accepting that this universe is not all there is. The laws of nature that science has discovered hold within the material world, with essentially unbreakable regularity. And we are justified in being extremely skeptical of deviations from them. However, that doesn't mean that we can accept as a mathematical certainty that miracles can never occur. Indeed, the idea that the universe is rational and predictable, and that the laws of nature are comprehensible, only make sense if the universe and its laws are the product of some kind of rational intelligence. Paradoxically, the regularity and order of the material universe itself pushes us to believe that that universe cannot be a self-contained system, and that in some sense mind must be prior to matter, and over and above it. Quantum physics, moreover, shows that nature at its most fundamental level is predictable, but it isn't deterministic, or comprehensible at all. What happens, exactly, when a sample of uranium goes through one half-life? What cause is there for one atom to decay and another not to? The answer is that there isn't any answer. The decay (or not) of every atom, the movement of every electron, is in some sense a little miracle, just as the assumption of Mary is a big one.
And once you concede that, then it becomes legitimate to accept at least the possibility that miraculous events, like the resurrection of Christ, the virgin birth, the healing of a leper, or the assumption of Mary are possible. One might add examples of divine apparitions- to people like the Emperor Constantine, or Joan of Arc, or (why restrict it to Christianity?) to people like Mirabai or Arda Viraf.
To paraphrase Chesterton, one can believe in miracles like one believes in the Javan rhinoceros. I don't ever expect to see a Javan rhinoceros, and they are sufficiently rare that if I ever was confronted by something that looked like a Javan rhinoceros, I wouldn't believe it. One would be safe to assume that every time you think you see a Javan rhinoceros, it's actually a misidentified rhinoceros of a different species. However, that isn't grounds for believing that Javan rhinoceroses don't exist, and never did. Obviously it isn't a perfect analogy, but still.
The real question we should ask about every supposed account of a miracle is whether it makes sense within the context of what we know about God, the world, and the testimony of the people involved. I don't believe that the face of Christ appears in a tortilla, because the God I believe in isn't arbitrary enough or petty enough to pull monkey tricks like that. I don't believe, as a general rule, in faith healing because I think that miracles are few and far between, and you should try your best to exhaust every other natural explanation before you resort to a supernatural one. (And in addition, the notion that some traveling televangelist can compel miracles on demand is demeaning as well as silly. As Christ said, you shall not tempt the Lord thy God.) I don't believe in the story that one of my friends in Africa once told me about a cat hybridizing with a civet. I don't know much about miracles but I do know something about mammalian taxonomy, enough to know that you can't hybridize two species that are as distinct as a cat and a civet.
But the story of Joan of Arc? Postulating a miracle seems to me like the best explanation there. What are the other explanations? Lying? Exaggeration for political purposes? Schizophrenia? Her symptoms, according to psychologists who have analyzed her court records, don't fit any known mental disease. She appears to have been too pure of heart to sustain a lie, and people don't take mere cynical 'exaggerations' to the stake with them. When you've ruled out the natural explanations, a supernatural one seems like it might make sense. And so it goes with things like the assumption of Mary. It makes sense within the context of the Christian story, and it is attested to by a wide variety of traditional sources. We know a few other animals that appear not to age in the way we understand it- why couldn't a divine miracle have chosen one person, out of the many, to never die? So let's suspend our disbelief, at least for today, and think about what might have- just possibly- happened on one night towards the later part of the first century, as Jerusalem burned under Roman siege, and a voice spoke out of the darkness to the woman who had held her dead son in her lap and wept tears over him, and said "Be not afraid."