Memory transference

When the elves first showed up in the North, they brought many wondrous inventions with them, but one of the strangest was their power of memory transference.

It's a learned magic, a skill taught to every elven child.  With this power, one person can touch an object and imbue it with a memory or a thought.  Another who knows the skill can recognize the tell-tale markings on the object and retrieve the memory into their own mind.  It's best done using a wand or a brush of some kind, but simple thoughts can even be conveyed with nothing but your fingertips.

You and I know this power as writing.  For us it's entirely unremarkable, but to an illiterate society, writing is magic.

An incident from the 1620s might illustrate this better.  One missionary sent a note to another asking for a fresh canoe, and the Hurons traveling with him were amazed that it worked:

They said that that little paper had spoken to my brother and had told him all the words I had uttered to them here, and that we were greater than all mankind.  They told the story to all, and were filled with astonishment and admiration at this mystery.

They weren't fools, just people confronted with a radical new technology.  Theirs was a world where the spoken word was the only way to convey thoughts.  Reading someone's thoughts from a piece of paper was tantamount to reading their mind from far away.

handwriting in the Cherokee writing system

In Signs in the Wilderness a similar discovery of writing is underway.  Humans, giants, and tree goblins got on just fine without it for all the thousands of years they've lived in the North.  Now elves have shown up and brought writing with them.

Giants are completely unimpressed.  They believe (like the ancient Gauls) that writing corrupts the mind, robbing you of your powers of memory.  To a degree, they're right.  No one who relies on the crutch of writing can remember the copious amounts of verse that an oral storyteller can recite.

Humans are in awe of the power of writing, but they don't have any widespread theories about it yet, other than considering it some kind of elven magic.

Goblins, however, know exactly what writing is.

Trapped spirits of the written word

Tree goblins have experts (shamans) who go into trances and dreams to contact the spirits and interact with them.  They understand that writing holds memories and can speak messages to those who listen.

When you come across a piece of writing, the prudent thing to do is to take it to a shaman.  With their skills, they can contact the spirit in the writing and find out what it knows: not just the message it was tasked with delivering, but other things the spirit has seen and heard.

For this reason, goblins are wary around writing, as they know the spirit trapped in the writing might be listening to every word they say.

Destroying a piece of writing in the right way can release the spirit inside.  If it's a good spirit (or at least a harmless one) a shaman would prefer to release it so it doesn't become angry and hurt people.  But if it's already vengeful and evil, the shaman will probably bury the written material far from home to keep the spirit from getting out and causing trouble.

Truth and superstition

This is probably all just superstition.  Writing probably works just like it does in our own world, with no spirits or memory magic involved.

But there's a chance that the goblins are right, that writing really does trap a spirit that remembers what you tell it.

Personally, I like to have about a 20% chance of truth to these kinds of beliefs.  That's low enough that it's probably false, but high enough that you can't discount it entirely.

If you're not sure about the nature of writing, roll to see what's really going on:

trapped spirits of the written word
the truth