First science fiction story in which a character discovers they are not human?

Question

Note: I just realized that in Greek mythology, demigods probably find out later in life (sometimes) that their mother was impregnated by a god. Also, "changelings" might be brought up by their human parents who do not immediately tell the changeling his origin. So I would like to qualify this -- I am interested in science fiction, not folk tales or mythology.

There are many stories, certainly by the 1960s, in which a human discovers he is a robot. There are plenty of stories also where a creature resembles a human but is not. I am pretty sure Frankenstein's creature knew he was artificial as did the creatures in Island of Dr. Moreau.

But a story in which an apparently human character discovers he is artificial or an alien, etc. is inherently more complex. In the 20th century stories where someone is living as human, they have artificial memories (like in Blade Runner or other PKD stories -- I think Dick had multiple stories with the theme); fake memories are a requirement almost which is perhaps why 19th science fiction would not have the idea of an artificial human discovering his true nature.

I was thinking HP Lovecraft has other people thinking a monster is human but not sure any of his stories have the monster its being deluded although a movie made from one of his stories had someone discovering he is a sea creature of some sort -- the movie is Dagon but the movie does not follow the original story very closely.

Just to emphasize, I know that creatures pretending to be humans probably predate even Greek mythology but again, I am looking for the creature itself not realizing its true nature, even if other characters already know and in fact keep this fact from it.

Answer 1

Another Lovecraft story, "The Outsider", is a closer fit for the question. It was published in Weird Tales in April 1926, and probably written about five years earlier.

The narrator first recalls his unusual life, but still assumes that he is human:

Beings must have cared for my needs, yet I can not recall any person except myself...

I do not recall hearing any human voice in all those years—not even my own

I merely regarded myself by instinct as akin to the youthful figures I saw drawn and painted in the books

On encountering some humans, he is disabused of that delusion:

I beheld in full, frightful vividness the inconceivable, indescribable, and unmentionable monstrosity which had by its simple appearance changed a merry company to a herd of delirious fugitives.

It is of course his own reflection, and he is a frightful rotting ghoul.

I know always that I am an outsider; a stranger in this century and among those who are still men.

Answer 2

1942: "Asylum", a novella by A. E. van Vogt, first published in Astounding Science-Fiction, May 1942, available at the Internet Archive. William Leigh thinks he's an Earthman until he learns that he's actually an undercover Great Galactic.

The Great Galactic, who had been William Leigh, smiled darkly and walked toward his captives. "It has been a most interesting experiment in deliberate splitting of personality. Three years ago, our time manipulators showed this opportunity of destroying the Dreeghs, who hitherto had escaped by reason of the vastness of our galaxy.

"And so I came to Earth, and here built up the character of William Leigh, reporter, complete with family and past history. It was necessary to withdraw into a special compartment of the brain some nine-tenths of my mind, and to drain completely an equal percentage of life energy.

Answer 3

To get the ball rolling, Superman first discovered he wasn't human in Superman Vol. 1 #61, published in November 1949.

SUPERMAN: Now I understand why I'm different from Earthmen! I'm not really from Earth at all—I'm from another planet—the planet Jor-El called Krypton!!

_{Superman Vol. 1 #61 (November, 1949)}

Answer 4

Since you mention Dagon, the relevant twist looks to be drawn heavily from The Shadow Over Innsmouth (written 1931, published 1936), in which the narrator recounts the discovery that he himself is descended from a group of sea-dwelling non-humans, beginning to change in appearance and ending the story abandoning humanity to join the "monsters".

However, by those criteria, Facts Concerning the Late Arthur Jermyn and His Family (1920, 1921) has it beat. In this case the revelation is the whole thing - Innsmouth is primarily about being stuck in a creepy cult-run town and trying to escape, but Jermyn is entirely about a character, and multiple generations of ancestors before him, learning that they're descended from intelligent apes and being horrified by the knowledge. It may not meet your criteria if "great-great-great grandma was an apefolk" isn't sufficiently exotic, but it certainly predates the other examples besides Kafka.

Answer 5

1955: The Tunnel Under the World, by Frederik Pohl

The protagonists discover that they're actually miniature robots in a miniature town, and their world is reset every night. Their town was destroyed in an explosion, and an advertising executive reconstructed the town with uploaded brain images of the now-dead residents programmed into robot bodies, to use as an experimental advertising lab. (If this is a spoiler for you, you need to read more Golden Age sci-fi!)

It is also one of the first examples of mind uploading stories, and is almost certainly the first where the uploaded people are initially unaware that they aren't living in the real world any more. As the OP says, there are many stories by the 60s where robots discover they're human, so I was surprised to find this concept was so (relatively) late.

It is available on Project Gutenberg.

Answer 6

In Franz Kafka's 1915 novella "Metamorphosis", the narrator, Gregor Samsa, awakes one morning to find he has transformed into a "monstrous vermin", some sort of insect, usually interpreted as a cockroach.

Full text at Project Gutenberg.

Answer 7

Also 1955, Brian Aldiss short story "Outside". Several people reside together in a house. One night one of them follows another housemate through a hidden door. The tone is very Ballardian.