Our brains deliberately make us forget things, to prevent insanity

Unhappy is he to whom the memories of childhood bring only fear and sadness.

At night, when the objective world has slunk back into its cavern and left dreamers to their own, there come inspirations and capabilities impossible at any less magical and quiet hour. No one knows whether or not he is a writer unless he has tried writing at night.

And where Nyarlathotep went, rest vanished, for the small hours were rent with the screams of nightmare.

Yog-Sothoth knows the gate. Yog-Sothoth is the gate. Yog-Sothoth is the key and guardian of the gate. Past, present, future, all are one in Yog-Sothoth. He knows where the Old Ones broke through of old, and where They shall break through again. He knows where They have trod earth's fields, and where They still tread them, and why no one can behold Them as They tread.

Any magazine-cover hack can splash paint around wildly and call it a nightmare, or a witches sabbath or a portrait of the devil; but only a great painter can make such a thing really scare or ring true. That's because only a real artist knows the anatomy of the terrible, or the physiology of fear.

I could not help feeling that they were evil things-- mountains of madness whose farther slopes looked out over some accursed ultimate abyss. That seething , half-luminous cloud-background held ineffable suggestions of a vague, ethereal beyondness far more than terrestrially spatial; and gave appalling reminders of the utter remoteness, separateness, desolation, and aeon-long death of this untrodden and unfathomed austral world.