"A Question of Credentials"
It hangs on the wall in a plain black frame:
a Doctor of Thaumaturgical Arts and Sciences
degree from Miskatonic University, a yellowed page
signed, in part, by John Carter (President) and
H. P. Lovecraft (Board of Trustees Chairman).
The gilt edging of the diploma gleams in the sun,
and the pen-and-ink illustration of the university
looks so real, even in miniature, that it almost
seems you could almost step right into it.
The professor himself is old and strange,
muttering to himself in dead languages.
People speak of him in whispers, too,
as if he is not one personality but many,
and they're forever uncertain who
might answer the door today.
No one quite wants to call him
insane, but then again, no one
actually calls him sane either.
He's still important, after all,
and no one else knows
the things he knows.
Madness, it seems, can be
a question of credentials.
* * *
The Cthulhu Mythos is a shared world founded by H. P. Lovecraft, inspired by his short story, "The Call of Cthulhu." From there it attracted many other writers. Among its most salient themes are hidden knowledge and insanity. It's often left to the reader's imagination whether a given character is possessed, has a split personality, or is just plain delusional.
Miskatonic University is a prestigious college in the Mythos. It's a good place to find books that will destroy your mind.