"Prophecy" is a metaphysically rich concept. Predictive prophecy flies in the face of classical physics, with majojr implications for the fundamental philosophical categories of freedom, causation, and the nature of knowledge.
There's a vast range of New Age and other postmodern discussion of prophecy, but I'm not aware of any objective discussion of the metaphysics that would make prophecy meaningful. It seems more like a visceral rejection of modern materialism in favor of a world more rich in meaning. You can just about sum up the intellectual underpinnings of all this in a bumper sticker: "Magic Happens."
The postmodernists are reacting to old-fashioned modernism, best represented by the methodological naturalists who believe that prophecy is a hoax. Fulfilled prophecies rarely persuade a true materialist--no matter how precise the prediction, they are precommitted to rule it a coincidence or "con." To the modern mind, "prophecy" is either intentionally false or worse than false--mere nonsense. For the truly secular thinker, prophecy is Macbeth's "tale told by an idiot, full of sound and fury, signifying nothing."
Theological liberals are "modernists" who aren't as committed to pure materialism as the methodolical naturalists, but liberal metaphysics also rules out any predictive power to prophecy. They view biblical prophecy exclusively as "forthtelling," not "foretelling"--revealing the character of God, not the future. Prophecy is God talking about Himself, not about the world.
Christians who still believe the Bible have more material to work with in thinking about prophecy. I haven't researched the theology of prophecy from an Eastern Orthodox or Roman Catholic perspective, so I will limit my comments to Protestantism.
- God does not know the future
- God knows the future but does not cause it
- God knows all possible futures and knows people so well he knows what they will choose
The first of these three positions has now become the starting point of "Open Theism," which holds that God knows all things, but does not know the future because the "future" does not exist. This is a refreshingly clear metaphysical position, which flies in the face of most of the old theology and most of the new physics.
The second Arminian position makes prophecy nothing more than a preview of coming attractions. I call it the "periscope model" of prophecy. The eternal God looks ahead at what is coming and reports back to an earlier time about events in their future. In this model, prophecy reveals God's omniscience but not His omnipotence--He sees the future but does not cause it. That means that prophecy should be "graded" on its truth value--the more precise the report, the greater the glory to the One who reported it. Unsurprisingly, most dispensationalists operate within this model, devoting their energies to explaining how the Old Testament prophecies to Israel will be literally fulfilled after the end of the Church Age.
The third Arminian position brings an entire set of possible futures into focus, enriching our discussion of fate and freedom. In this model, prophecy reveals God's wisdom as well as His knowledge--the One who counted every hair upon our heads knows our hearts so well that He knows our free choices before we make them. This understanding of prophecy enables us to make sense of prophetic warnings that never come true, like Jonah's message to Ninevah. God isn't just a journalist reporting what is coming in the future; He is an actor in the drama Who shapes what is to come.
Calvinists don't tend to worry about the metaphysics of prophecy. God is absolutely sovereign over past, present, and future. He is neither a reporter nor an actor--He is the author of the story we are in. Prophecy has an esthetic dimension--it "foreshadows" what is coming, adding interest to the plot.