harry potter - Why does the Department of Mysteries keep prophecies?

What's the main reason why the Department of Mysteries keep prophecies?

The Keeper of the Hall is a Bureaucratic witch or wizard who orders and maintains the Records placed on the numerous shelves that comprise most of the Hall's interior. Presumably, after the Records are correctly assorted, stringent anti-theft spells are placed upon each and every one of them, allowing only those to whom the Prophecies refer the authority to remove them from their places. _{http://harrypotter.wikia.com/wiki/Prophecy_Record}

As far as I know, the Department of Mysteries is the department where they put recordings of prophecies, and that includes the prophecy about Voldemort and the one who's supposed to conquer his power. They are recorded and then put into those glass orbs.

Well, for this part, it seems reasonable that this is one of the most important prophecies since the Ministry of Magic wanted to find out how to conquer Voldemort's lust for power.

But I'm puzzled with this. Why do they even keep them? What significance do those prophecies have? There may also be certain items there that are very important or can play a great role for magic. But I can't remember why they keep these prophecies. Do they need them for future reference, fate guesswork, etc.?

Things to remember:

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  The Department of Mysteries could have just stored the important prophecies. So there's a possibility that they stored those prophecies for an important reason or maybe a reference.

  
  


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  I have a theory that they stored those prophecies for future references. There's a possibility that they will need it for a certain reason which I don't know.

  
  

Answer

Because they study mysterious stuff.

The Department of Mysteries is all about studying and unravelling the deepest and most inscrutable mysteries of magic and the universe. Prophecies count as mysterious, so they're all stored there, where the people working in that Department can study them at their leisure.

Why does the Department of Mysteries keep ...

• a locked room containing the essence of love?


• an archway with a veil containing the essence of death?


• an entire hall full of bottled prophecies?

It's all for the same reason: they study mysteries.

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As for your point that they could have just stored the important prophecies ... well, how do you know beforehand which ones are likely to be important? The whole point of prophecies is that they:

1. say something about the future, and


2. are often cryptic, their meaning hard to unravel.

Stuck here in the present, we can't know which statements about the future are likely to be important, even assuming we could understand those statements in the first place. OK, the one about Voldemort and Harry Potter was obviously significant, but that's an exception rather than a rule. Remember the butterfly effect: it's often impossible to tell beforehand which events are going to be significant and which aren't. Let's say there was a prophecy about the unrequited love of a poor boy from Spinner's End - who would have thought that that would end up having great significance in the history of the wizarding world? Or a prophecy about how Barty Crouch's son wouldn't take after his father ... or one about how a boy once thought to be a Squib would one day kill a snake. All of these are things which a priori might have appeared insignificant, but in hindsight turned out to be crucial.