Quotes / I Know Your True Name

Geralt: You're clearly not human. What are you? A demon? A djinn?
O'Dimm: Do you truly wish to know?
Geralt: Yes.
O'Dimm: No, Geralt, you don't. This one time I will spare you and not grant your wish. (...) All who have learned my true name are dead, mad, or both. But I still need you.
The Witcher 3: Wild Hunt, Hearts of Stone

"Fear names. Names have power in identity. Others can use names as weapons. Names are a hook that can be used to track you... Remain nameless, and you shall be safe.

I am The Nameless One."

Only I know your true purpose in this world, Lombax. Only I know your true name!

(a Macbeth-esque witch/Carrionite alien howls in pain/rage and vanishes)
Martha: What did you do?
Tenth Doctor: I named her. The power of a name. That's old magic.

Rose:I know your true name, Baba Yaga. Do you wish me to shout it now, so that all of the animals of the forest, all the birds of the air, every passing nixie and boggart will know it too? Your name will be as common as crab-grass. Would you like that, Baba Yaga?
Baba Yaga: You're lying. You do not know my name.
Rose: Perhaps. Do you wish to find out how loudly I can shout?
The Books of Magic, "Land of Summer's Twilight"

You know enough not to look in my eyes, but you do not know not to ask me my name?
Constantine, Sunshine by Robin McKinley

Names, capital N, have power. If you know something's name, you automatically have a conduit with which you can reach out and touch it, a way to home in on it with magic. Sometimes this can be a really bad idea. Speak the Name of a big, bad, spiritual entity and you might be able to touch it, sure—but it can touch you right back, and the big boys tend to do it a lot harder than any mortal.
Harry Dresden, Small Favor

The name is the thing, and the true name is the true thing.

Look, my name, my "real name", that is not the point. The name I chose is the Doctor. The name you choose, it's like a promise you make.
— The Eleventh Doctor, "The Name of the Doctor"

"A long time ago, when the world was so new nothing had a name, something woke up. It learned all about what was and what would be... but most of all it learned what couldn't be, what shouldn't be. And it gave those things names, names it wrote on indestructible pages, because a namer has mastery of the named."
Diabolique, Darkhold #10

In exchange for sponsorship from the Children, the first tribe became their acolytes; the mortals accepted the burden of remembering their masters' existence when They vanquished them from mortal memory. The first tribe accepted the bargain in bad faith, however, believing that by knowing the true names of these malignant creatures they would have true power over them. Such is the ignorance of primitive people. Knowing something's true name gives it sway over you as well. Power is never free for the taking or for the giving.
Vampire: The Masquerade - Clanbook: Baali