You've lost your spellbook. Now what?

[Lord Torath]

How does one relearn spells after losing your spellbook?

You have learned spells, and copied them into your spellbook. Do you still know those spells? If you gain access to a spellbook (captured, bought, borrowed, "borrowed", scryed on, etc.) that contains a spell you previously learned, can you memorize that spell (following normal rules for spell memorization), or do you need to roll again to "relearn" it first?

If you still have spells memorized, can you add them to a spellbook (assuming there are sufficient blank pages available)?

Can you just spend some time (maybe several hours per spell level) to write down the formulas (formulae?) of the spells you learned in a new spellbook?

I guess what I'm really asking is: If you lose your spellbook, have you "unlearned" those spells?

Edit: I've also asked this question over on Dragonsfoot, a site more dedicated to 2nd Edition. If you've answered there, don't feel like you need to answer here, too. Unless you want to.

[LibraryOgre]

The fetishization of the spellbook-as-an-object was always a bit weird in AD&D. Like, "written in your spellbook" was supposed to be a thing, without any indication that you actually know anything not in your spellbook.

As we've established on Dragonsfoot (), you don't need Read Magic to read someone else's spellbook, so co-opting a spellbook is probably the faster option. I think, though, lacking someone else's spellbook to co-opt, I would let a wizard rewrite his spellbook from "memory", without all the work of preparation going into memorizing a spell. It's probably not as punitive as AD&D would like me to be, but I think "A few weeks without your spellbook, and a substantial outlay of money and time to recreate it" is enough punishment for "losing" your spellbook.

[sktarq]

Only time i ever saw it come up it was basically as above but had to gain access (aka trade a future favor) to an arcane library to brush up on stuff...I want to say getting your own arcane library of sufficient potency was an option but it was so long ago details are fuzzy)

[hifidelity2]

I have
- Allowed them to re-write the spells in memory into a new book (afterall you know them as they are in your memory)
- Any others then you will need to find another book / other source of info to re-copy them into your new book
- IIRC I allowed an INT roll and adjusted it by the spell level for each spell - so you probably remembered all the easy, low level spells - to put them into your book without the need to find a source

it become a set of adventures for the PC's to do esp for the higher level, harder to find spells