Never could I tell, try as I might, what it actually was that I saw; nor could the still face tell, for although it must have seen more than I did, i… - H. P. Lovecraft

The Man of Truth has learned that Illusion is the One Reality, and that Substance is the Great Impostor.

I'll tell you something of the forbidden horrors she led me into - something of the age-old horrors that even now are festering in out-of-the-way corners with a few monstrous priests to keep them alive. Some people know things about the universe that nobody ought to know, and can do things that nobody ought to be able to do.

It lumbered slobberingly into sight and gropingly squeezed Its gelatinous green immensity through the black doorway into the tainted outside air of that poison city of madness. … The Thing cannot be described — there is no language for such abysms of shrieking and immemorial lunacy, such eldritch contradictions of all matter, force, and cosmic order.