The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of infinity, and it was not meant that we should voyage far. The sciences, each straining in its own direction, have hitherto harmed us little; but some day the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the deadly light into the peace and safety of a new dark age.
"You humans build little worlds, little stories, little shells around your minds and that keeps infinity at bay and allows you to wake up in the morning without screaming!"
—The Hiver, A Hat Full of Sky
"Just when Mankind begins to think the galaxy is his to explore and exploit, we find a system like Seneschal and realize we are defenseless babes crawling too far from our cribs."
— Navigator Sollenn Durst, Warhammer 40,000
"Wisdom is but beginning of fear."
— Inquisitorial Proverb, Warhammer 40,000
"Cthulhu makes Gozer look like Little Mary Sunshine."
— Egon Spengler, The Real Ghostbusters
"It came from beyond the extreme reaches of our reality,
It came to laugh at our naive existences.
I am puzzled by the truth that slips through my hands even as I cover my ears.
Where in this thin body do I find the strength to stand?"
— Partial translation of "Uninstall", opening theme for Bokurano
"My kind transcends your very understanding. We are each a nation; independent. Free of all weakness. You cannot even grasp the nature of our existence."
—Sovereign, Mass Effect
"For the fish, the lake in which he lives is the universe. What does the fish think when he is jerked up by the mouth through the silver limits of existence and into a new universe where the air drowns him and the light is blue madness? Where huge bipeds with no gills stuff it into a suffocating box and cover it with wet weeds to die?"
— The Man In Black, The Gunslinger
"Evil never dies. Darkness never retreats. In the cracks and the crevices of our society there are monsters undreamed of by the rank and file of humanity. I've been there. I've seen them. They exist in the spaces between things, in the folds of existence where we can't find them. Sometimes they cross over, sometimes they manifest, and all hell breaks loose. Only this is not Hell, nor Heaven. This is like nothing anyone has ever understood. This is pure evil, pure destruction. This is the Apocalypse."
— Maj. Gen. Reginald Fairfield, U.S. Army (Ret.), 25 FEB 1994 (Delta Green core book opening fiction piece)
"In this world, is the destiny of mankind controlled by some transcendental entity or law? Is it like the hand of God hovering above? At least it is true that man has no control, even over his own will."
I have seen the dark universe yawning,
Where the black planets roll without aim;
Where they roll in their horror unheeded
Without knowledge or lustre or name.
See, Lovecraft's stories haven't remained popular so long just because his monsters are scary. They endure because his monsters are metaphors for existential alienation. It's not the appearance of the monsters in his stories, it's the reality of them, the fact that they exist. Their existence alone proves that humanity is doomed and that all our hopes and dreams are stupid. Running into one of Lovecraft's Elder Gods is like finding a strange pair of underwear in your bed and realizing that your spouse is cheating on you. It's not the underwear itself that's stabbing you in the heart; it's the betrayal it represents. Lovecraft's monsters are proof to the protagonist that the universe is not benevolent. Finding strange underwear might mean that your spouse never loved you; stumbling upon a Lovecraft creature means that God never loved you.