"Did you think to kill me? There's no flesh or blood within this cloak to kill. There's only an idea. Ideas are bulletproof."
— V, V for Vendetta
"The Devil is an idea. In all those civilizations, just an idea. But an idea is hard to kill. An idea could escape."
— The Tenth Doctor, Doctor Who, "The Satan Pit"
Over time, any sentence uttered long and loud enough becomes fixed. Becomes a truth. Provided, of course, you can outlast the dissent and silence your opponents. But should you succeed – and remove all challengers – then what remains is, by default, now true.
Is it truth in some objective sense? No. But how does one ever achieve an objective point of view? The answer is you don't. It is literally, physically impossible. There are too many variables. Too many fields and formulae to consider. We can try, of course. We can inch closer and closer to a revelation. But we'll never reach it. Not ever...
And so I have realized, that so long as The Templars exist, they will attempt to bend reality to their will. They recognize there is no such thing as an absolute truth – or if there is – we are hopelessly under-equipped to recognize it. And so in its place, they seek to create their own explanation. It is the guiding principle of their so-named "New World Order"; to reshape existence in their own image. It is not about artifacts. Not about men. These are merely tools. It's about concepts. Clever of them. For how does one wage war against a concept?
It is the perfect weapon. It lacks a physical form yet can alter the world around us in numerous, often violent ways. You cannot kill a creed. Even if you kill all of its adherents, destroy all of its writings – these are a reprieve at best. Some one, some day, will rediscover it. Reinvent it. I believe that even we, the Assassins, have simply re-discovered an Order that predates the Old Man himself...
—Altaïr Ibn-La'Ahad, Assassins Creed II, "Codex"
"There is one thing stronger than all the armies in the world. An idea whose time has come."
"If you gun down the messenger
You guarantee that he will be made into a saint
A martyr of the free word."
- Epica, "Martyr of the Free Word"
"Ideas by man and only that will last
And over time we've learned from the past
That no man's fit to rule the world alone
A man will die but not his ideas."
- Ace Of Base, "Happy Nation"
"Your kind is always looking for villains. So much better to have something- someone -to fight than face the reality of it: that what you're fighting isn't physical; it isn't even metaphysical! It's an idea made real. You can't shoot fireballs at an idea. Ideas are like viruses- invisible, all-pervasive... invincible."
— Freddy Beaumont, The Secret World
"It has been dead for a thousand years; but its idea is still alive. Have you ever fought an idea? It has no weapon to destroy, no body to kill."
— Gowron, Star Trek: The Next Generation
"I'd expect you to say that; you never truly believed in us. Cerberus isn't just an organization or the people behind it. Cerberus is an idea. That idea is not so easily destroyed."
— The Illusive Man, Mass Effect 3
You can destroy planets, but you can never destroy what I am, "friend".
—Son Goku to Freeza, Dragon Ball Z
"You can put out the candle, but you can't put out the fire.
Once the flame begins to catch, the wind will blow it higher."
— Peter Gabriel, Biko
"Even when your kind appears to triumph...Still we rise again. And do you know why? It is because the Order is born of a realization. We require no creed, no indoctrination by desperate old men. All we need is that the world be as it is. And THIS is why the Templars will never be destroyed!"
— Haytham Kenway, Assassins Creed III
"The open source movement gave every idea an army of researchers. They turned military secrets into public knowledge, and children's science kits into biowarfare labs. That's how the Jews became extinct, why China is full of zombies, and why red hair is a death sentence. Two-thirds of the world's population died because of bigotry, insanity, or ancestral hatred. Because of ideas. There's only one way to kill an idea: you have to kill every person who holds it."
— Jacob Doe, Genocide Man
"I am the one thing you can never kill. I am Hope."
— Kelsier's last words, Mistborn: The Final Empire