Robert Bloch said this quote

“ Mind you, I cannot swear that my story is true. It may have been a dream; or worse, a symptom of some severe mental disorder. But I believe it is true. After all, how are we to know what things there are on earth? Strange monstrosities still exist, and foul, incredible perversions. Every war, each new geographical or scientific discovery, brings to light some new bit of ghastly evidence that the world is not altogether the same place we fondly imagine it to be. Sometimes peculiar incidents occur which hint of utter madness.How can we be sure that our smug conceptions of reality actually exist? To one man in a million dreadful knowledge is revealed, and the rest of us remain mercifully ignorant. There have been travelers who never came back, and research workers who disappeared. Some of those who did return were deemed mad because of what they told, and others sensibly concealed the wisdom that had so horribly been revealed. Blind as we are, we know a little of what lurks beneath our normal life. There have been tales of sea serpents and creatures of the deep; legends of dwarfs and giants; records of queer medical horrors and unnatural births. Stunted nightmares of men's personalities have blossomed into being under the awful stimulus of war, or pestilence, or famine. There have been cannibals, necrophiles, and ghouls; loathsome rites of worship and sacrifice; maniacal murders, and blasphemous crimes. When I think, then, of what I saw and heard, and compare it with certain other grotesque and unbelievable authenticities, I begin to fear for my reason. ”