These Are Things Man Was Not Meant to Know

Everything About Fiction You Never Wanted to Know.
"Learn from me, if not by my precepts, at least by my example, how dangerous is the acquirement of knowledge, and how much happier that man is who believes his native town to be the world, than he who aspires to become greater than his nature will allow."
Victor Frankenstein, Frankenstein

Do not read this page. Just click "back", or close this page right now. Your sanity, nay the fate of all mankind, will be in danger.

You didn't listen. Damn you. Don't you know this knowledge was kept secret for a reason? Your feeble, mortal minds cannot comprehend the vast complexity of what you are seeking to learn. Pray that complete madness is the worst consequence of your transgression. Just don't blame us. You Have Been Warned.

If you still wish to go further, see the Sub Tropes below:

It's a pretty safe guess, though don't confirm it, that these things resemble Mind Screw and are a Mind Rape.

Learning this can cause you to Go Mad from the Revelation, and is a standard trope of a Cosmic Horror Story. A major reason on why Curiosity Is a Crapshoot. If you can even read and/or understand these final words, pity the Mad Scientist who seeks out this knowledge, for his experiments will Go Horribly Right.

Not to be confused with You Do NOT Want to Know. If your mind has become a horrifying alien monstrosity by this point, avoid interacting with humans, Humanity Is Infectious.

For things that men (the gender) are not supposed to know see Women's Mysteries

Examples of These Are Things Man Was Not Meant to Know include:

Anime and Manga

  • In Fullmetal Alchemist, performing a forbidden human transmutation will take you to the Gate, where, along with being maimed in some way, you get to look inside and see 'Truth', which, as Izumi stated, looked like hell to her.
    • Almost all alchemists die doing so. It is implied by Izumi that just surviving it is a very serious feat. Alphonse would have died if his brother had not brought him back. By the end of the story it is revealed that Father was unable to find enough living alchemists who have survived that as required for his Evil Plan to work.
    • Also, learning that the Philosopher's Stone is created by sacrificing mass numbers of human lives has driven many who have sought its power insane. Scar's brother was one of the people thusly afflicted in the first anime.

Comic Books

  • When Doctor Strange meets the Living Tribunal (the most powerful being in the Marvel Universe who isn't God), he shows Strange how the Universe was created and Strange quickly averts his eyes, paraphrasing this trope.
  • John Byrne's "Trial of Galactus" arc in Fantastic Four ended this way when Byrne wrote himself into the final issue. The Watcher snatched him from his home and brought him to the cosmic tribunal, stating that he was the "chronicler" of the Fantastic Four's adventures and thus needed to be there to witness as Reed Richards was brought to trial for the destruction of the Skrull throneworld; he was accused of genocide because he saved the life of Galactus some time before. Various cosmic beings, including Galactus himself and Odin, arrived to testify on Reed's behalf. In the end, Eternity showed everyone assembled the True Purpose of Galactus. The last page had the Watcher warning Byrne that as he wrote this story, many of the details would escape his memory, as the human mind wasn't meant to hold such knowledge.
  • In The DCU, the Anti-Life Equation is a mathematical proof that life, hope and freedom are all pointless. Any sentient being who's forced to comprehend the Equation instantly becomes a mindless drone. Darkseid's ultimate goal is to rule the Universe Multiverse Omniverse with this.
  • Arguably, this is what drove Teen Titans' Jericho to insanity/death/resurrection/insanity - having Body Surf as one's superpower, and then trying to possess an Eldritch Abomination like Trigon? Yeah, Joey... while your dad is evil, Raven's is worse.
  • In Ultimate Spider-Man, Spidey has something of an existential crisis after a brief brush with the supernatural, saying later that he's "Seeing things he shouldn't." The inciting incident was actually a relatively tame (by reader standards) vampire story, but his seemingly outsize reaction reminds us of how mentally devastating commonplace fictional tropes would be if ever actually encountered.


  • In the movie Pi, the protagonist Max is on the verge of uncovering a number that unlocks the pattern of the universe. A group of Orthodox Jews believes that it is the true name of God. However, the number overwhelms anyone or anything that tries to compute it. Ultimately Max abandons his quest and chooses to simply live life in ignorance, possibly drilling out his mathematical genius to escape the number's curse.
    • Another interpretation of the movie's ending is that there is no secret pattern. Max and the Orthodox Jews simply have become obsessed with finding such a pattern, and because of that start seeing it everywhere. However, in the end Max realizes there's no unifying pattern to existence, it is random. This randomness is symbolized by the leaves in the tree Max is watching in the final scene. What he drills out of his head is the obsession to find a pattern.
  • The Mothman Prophecies

John: Didn't you need to know?
Leek: (Beat) We're not allowed to know.


  • Discworld had Things Man Was Not Meant to Know Of.
    • The Igors of Discworld's Thief of Time, strictly speaking don't believe that there are TMWNMTK, but even they find some obvious stuff that they'd rather not know, such as how it feels to have every single particle of your body sucked through a small hole.
    • In general, Terry Pratchett likes to have fun with this trope. For example, The Unseen University library has books that no man can read without dying or going mad, but the Librarian is an orangutan, so he's perfectly safe.
      • Although even he reads the most potent of these, the Necrotelicomnicon, from behind a smoked-glass visor, just to be on the safe side.
  • The Hitchhiker's Guide to the Galaxy:
    • According the The Guide, there's a theory that if any one person ends up knowing both the Ultimate Answer and the Ultimate Question, the universe will end and be replaced by something even more bizarre and incomprehensible. There are other theories that state that this has already happened.
    • The most horrible torture device in the normal universe is the Infinite Perspective Vortex, which works by showing you the whole universe, and how insignificant you are. And it's powered by a cupcake. It IS possible to survive the Infinite Perspective Vortex by being the most important person in the (current) universe, but you'll walk away an even bigger Jerkass after being told by a machine that the universe revolves around you.
    • Give a witness too much truth serum, in a court, and he'll tell "the whole truth". ALL of it. Oddly enough, the guy who comes to know all the truth doesn't seem to become mad - those who hear from him, though, do. This may be because he knows all the truth, whereas the listeners only know the part they hear. Oddly enough again, most of the good bits are about frogs.
  • In Robert A. Heinlein's novel Methuselah's Children, Slayton Ford goes mad when he meets the Sufficiently Advanced Aliens. Interestingly, after Ford goes mad, Lazarus Long mentions he is afraid that if he met them he wouldn't go mad.
  • In the Robert A. Heinlein short story By His Bootstraps, Bob Wilson sees one of the High Ones through a time viewer and almost loses his mind. It was the emotions the High One was feeling that caused his discomfort - an overwhelming mixture of sadness, tragedy, grief and weariness.
  • H.P. Lovecraft's work tends to be full of things that should not be named or known to man. Some variant of the line "there are things in the world man was never meant to know" is frequently said near the end of his stories, just as the protagonist has some (literally) mind-blowing revelation about the nature of the universe and our place in it, or at the beginning when he starts to recount his story that ends like that.
    • The Shadow Over Innsmouth actually makes the trope name a double entendre: Obed Marsh "knew" something man was not meant to "know" in the Biblical sense.
  • There's a story by Isaac Asimov where a man with access to a super computer that can tell you anything if you know how to ask tries to discover the source of humor. He tries because he himself is a wonderful, though nonprofessional, comedian. Eventually it turns out the sense of humor was an alien experiment that would be halted as soon as anyone figured out that it was so, meaning he destroyed everyone's sense of humor. Plus, the aliens will now replace humor with something else. Who knows what?
  • "The Nine Billion Names of God". A group of monks use a computer to write down every name of God, reducing the time it would take to do so from 15,000 years to 1,000 days. When every name is finally recorded, humanity's purpose is fulfilled, and God unmakes the universe.
  • In "Macroscope" by Piers Anthony, use of the title machine accesses a mathematical sequence which is shown to whomever uses the device. It destroys the intelligence of anyone above a certain IQ who hasn't evolved beyond violent tendencies.
  • A Larry Niven short story set in Draco's Tavern involves a priest asking one of the ubiquitous Chirpsithtra (who seem to know everything about anything) about the existence of God. The Chirp responds with a story of a race of beings who set about to prove the non/existence of an afterlife. The Chirps lost contact with them and the next time a trade ship visited, they found the entire race had calmly and orderly committed suicide. Whatever they had discovered, it was something that had convinced the entire race they were better off dead, and something the Chirps were not particularly interested in knowing. Rick later explained relating this particular story was the Chirp's way of politely saying "none of your business."
  • In the Stephen King short story "The Jaunt", teleportation is possible... but you'd better be unconscious when you do it. Anyone who goes through the process awake is driven completely insane and often dies. The man they tested it on managed to croak out "it's eternity in there" before dying. The story follows a family who is about to Jaunt to Mars. Their father tells them the history of the Jaunt process to kill the time before it is their turn, and when they go through, the young son holds his breath when the knockout gas is administered. A split second later, on the other side, his hair has gone completely white and the boy is quite mad, cackling that the Jaunt was much longer than anyone thinks before he rips his own eyes out.
  • Paradise Lost: The angel Raphael answers all of Adam's questions about the War in Heaven, the creation of the world, and the laws of the cosmos (although he doesn't find knowledge of the latter at all practical or useful for humans), but when Adam asks him if angels express love, like humans, Raphael blushes "celestial rosie red" and quickly explains that yes, angels "love," too. How? Whoah, look at the sun, time to go! Live long and prosper!
  • In Robert E. Howard's Conan the Barbarian story "A Witch Shall Be Born" Salome was turned out by the magician who raised her for not being sufficiently interested in this for its own sake.

"He drove me from him at last, saying that I was but a common witch in spite of his teachings, and not fit to command the mighty sorcery he would have taught me. He would have made me queen of the world and ruled the nations through me, he said, but I was only a harlot of darkness. But what of it? I could never endure to seclude myself in a golden tower, and spend the long hours staring into a crystal globe, mumbling over incantations written on serpent's skin in the blood of virgins, poring over musty volumes in forgotten languages.
"He said I was but an earthly sprite, knowing naught of the deeper gulfs of cosmic sorcery. Well, this world contains all I desire--power, and pomp, and glittering pageantry, handsome men and soft women for my paramours and my slaves."

  • In Algernon Blackwood's "The Man Who Found Out", an explorer discovers the long-lost Tablets of the Gods, reputed to explain the true purpose of human existence. Reading their translation causes him to lose the will to live, and the friend who inherits the Tablets destroys the text and has his own memory of reading it erased via hypnosis.
  • Twenty Thousand Leagues Under the Sea: For the man of the 19th century, reaching the South Pole would be something man was not mean to achieve. In this novel, is lampshaded by Ned Land opinion about the beauty of the South Pole’s icebergs (and those words were said just before the Nautilus will be trapped by them and the crew will go Almost Out of Oxygen).

"it's a wonderful sight! Isn't it, Ned?"
"Oh damnation, yes!" Ned Land shot back. "It's superb! I'm furious that I have to admit it. Nobody has ever seen the like. But this sight could cost us dearly. And in all honesty, I think we're looking at things God never intended for human eyes."

  • Played with in the Star Trek: The Next Generation novel Metamorphosis. Watching Geordi's frustration at being unable to determine how an alien artifact works, Data suggests that they were not meant to know. After Geordi both rejects the idea and expresses disgust at Data of all people proposing a mystical explanation for something, Data explains that he means the artifact's creators may have designed it so that its inner workings could not be analyzed.
  • In The Dresden Files novel Turn Coat, Harry uses his Wizard's Sight[1] to figure out what exactly is following him. He glimpses the Skinwalker...and comes back to himself about three minutes later, having almost crashed his car, gibbering uncontrollably. He gets himself under control, tries to remember what he saw...and comes back to himself five minutes later, incoherent and barely in control of himself. He realizes that driving is a bad idea, gets out of his car and starts walking to get help when his thoughts just barely brush against the idea of what he saw...and he comes back to himself, curled into a fetal position on the sidewalk, crying and in physical pain.
  • Harry Potter:

There is a room in the Department of Mysteries that is kept locked at all times. It contains a force that is at once more wonderful and more terrible than death, than human intelligence, than the forces of nature. It is also, perhaps, the most mysterious of the many subjects for study that reside there. It is the power held within that room that you possess in such quantities and which Voldemort has not at all.

Live Action TV

  • After seeing Ed Wood's Bride of the Monster, the line "He tampered in God's domain," became almost a Catch Phrase for Crow T. Robot.
  • In Being Human (UK), there is a secret only the dead know. When Annie tells this secret to Owen, her murderer, it torments him, driving him to confess his crimes.
  • On Babylon 5, a Dilgar war criminal buys her way out of prosecution by offering the formula for an immortality serum. The catch is that the formula's ingredients must be fatally extracted from sentient beings, making it a surefire trigger for mass murder and a thing Sentient Beings Were Not Meant To Know. The Vorlons, fortunately, agreed.
    • Also on B5, apparently nearly every sentient race has developed a dish almost identical to Swedish meatballs, when G'kar comments on this, his response is.

"It is one of the great mysteries of the universe, that we will either never know the answer to, or which would drive you quite mad if you did."

  • In Battlestar Galactica, the Final Five are treated like things Cylons are not meant to know. D'Anna Biers grows an obsession with them, repeatedly committing suicide to glimpse into the place between life and death in a quest to find out about them. When she finally does get a glimpse, it results with her suffering from Psychic Nosebleed, followed by death.
    • Possibly subverted though. The Final Five were rendered things-Cylons-are-not-meant-to-know because Model One/Cavil made them so. Their origins are far more mundane than the Cylons think.
  • Donna suffers the brown note variety in Doctor Who when her conscious is merged with the doctor's. 900+ years of time lord knowledge and experience shoved into her human brain nearly kills her.
  • Monty Python's Flying Circus had "The Funniest Joke In The World" sketch; about a man who wrote a joke so hilarious, everyone who read or heard it died. It goes without saying that it was played for (fortunately non-lethal) laughs.


  • Revelation 10:4 "When the seven thunders spoke, I was about to write. But I heard a voice from heaven saying; Keep secret what the seven thunders said, and do not write it down."

Tabletop Games

  • Warhammer 40,000. You really, really, really, really don't want to know. Really.
  • The Illuminati: New World Order card game has a card called "Secrets Man Was Not Meant to Know". There was a gag card appropriately titled "Secrets Man Was Not Meant to Know In the Biblical Sense".
  • GURPS IOU (Illuminati University) had a class in the Thaumaturgy department called "Things Men Were Not Meant to Know". The next class was "Men Things Were Not Meant to Know".
    • Also what the O in IOU stands for.
  • Appropriately, Munchkin Cthulhu has a card called "Learn Things Man Was Not Meant to Know: Go Up a Level."
  • The Truth, upon which the World of Progress in SLA Industries is precariously balanced, can be used to grant incredible power to anyone who knows it and understands how to manipulate it. Most people—upon discovering it—are driven infinitely insane and/or die horribly. It's been stated that if enough people discovered The Truth, the entire universe would disappear in a puff of logic and cease to exist...
  • Mage: The Awakening's Guardians of the Veil justify many of their actions with the idea that there are plenty of things that man was not meant to know (and not quite as many things which even mages shouldn't). They are often at odds with the Mysterium, who believe man is supposed to know everything.
    • There's a Legacy, the Logophages, devoted entirely to this idea—it's their job to not only track down the things man must not know, but to make sure they remain unknown, even to themselves. Needless to say, they're masters of memory alteration and occasionally give their own brain a good scrubbing just in case.
  • Call of Cthulhu. Everything in the game is full of things man (and woman) was not meant to know, and so you are eventually either incredibly ignorant or incredibly insane. Maybe both simultaneously.
    • Maybe the most common Co C joke is just the single sentence "I read the book".
  • In Exalted a demon exists called Orabilis; his title is The End of All Wisdom. He builds libraries, and it is his will that demons and men read in them and grow wise. Sometimes people take two and two, though, and get this trope out of it; at that point, he's free to pursue you out of Hell, drag you back, and cast you into the sky where you spend a thousand years dying.
  • The Works by Phil Foglio features Agatha Heterodyne reading a book titled "Things Man Was Not Meant To Know"... and looking less than impressed, since she is a woman.
  • Cthulhu 500, a racing car cardgame, has this in spades. (It is Cthulhu, after all.) You can drive The Car Man Was Not Meant To Drive, equipped with The Wheels Man Was Not Meant To Mount and The Mudflaps Man Was Not Meant To Ogle, all paid for by The Sponsor That Must Not Be Named.
  • A lot about the world in Kult. OTOH, you have to learn this if you want to break free from it.
  • In the World of Warcraft tabletop RPG, the ability to speak and write in the demonic language will slowly eat away at the sanity of mortals who dare to learn it. Characters who possess this forbidden knowledge must make a saving throw every year, with each failure resulting in the permanent loss of a wisdom point. Meaning that unless you have consistently good rolls your character will eventually go insane and die.


  • Happens to Lariska when Tren Krom Mind Rapes her in Bionicle, as his search for information in her mind also causes her to get glimses into his mind.

Video Games

  • Diablo II plays this one straight when Marius witnesses Diablo's transformation. He even says it "was not meant for mortal eyes."
  • Eternal Darkness: Sanity's Requiem plays on this trope with one of the characters going insane (well he wasn't really but he sure sounded like it) after seeing "beyond the veil".

Oh...oh gibbering insanity wrought in flesh as though an artist sculpted it! Created from nothing by their mistress Xel'lotath, a canvas as grotesque as any!! Their bodies made no sense - no heads, no organs - an empty husk devoid of the trappings of nature... But it shrieked!!! A mockery of reason, both natural and mental!! A blasphemy from beyond the Veil!! The veil has opened!! And we should not see beyond!! We...we weren't meant to...never...ever...meant to!! Oh, give us the blessing of ignorance, the happiness of oblivion... Innocence can only be tainted, never returned!

  • In La-Mulana, the Skimpy Swimsuit--and a nice screen-sized shot of Lemeza wearing it--is your final reward for beating Hell Temple. Duracuets warns you on multiple occasions that the reward was not meant to be seen and that you may regret obtaining it.
  • Rayman 3 features a weaponized thing Man (or rather, a cute little fairy-like species) was not meant to know. There is a secret so horrible that it corrupts anyone who hears it. A single member of the species somehow learned it, and he captures others and whispers it to them, then lets them whisper it to others, like an intellectual Zombie Apocalypse. It'd be horrific if the entire game weren't Played for Laughs.
  • Invoked by Theo in Persona 3 Portable when he refuses to tell the player what was in the takoyaki they just ate.

Theo: “There are things your kind is better off not knowing.” So I’ve been taught, which means... I mustn’t... But using THAT for cooking...

  • The Bureau's interrogation and torturing techniques in Escape Velocity: Nova are alluded to but never explained. All that other characters will say of them is that they are "sickening" and too horrible to describe. In one plot line, the player is captured and suffers it first-hand: The game dialogue will only tell you that what you experienced is too awful to remember, and that for the rest of your life whenever you even attempt to recall what you have been through, you will lapse into incoherent, terrified screaming.
  • Call of Cthulhu: Dark Corners of the Earth has the main character, a private detective, progressively learn more and more of these until he discovers he has been time-switched by the Great Race of Yith (a la A Resection of Time) which contributes to his suicide.
  • There exists... something... in Star Control 2 that causes horrible death to anyone who learns about it. This happened to the Androsynth, and to one scientist in your landing party, who read their science notes leading up to the event. It is repeatedly stated by those in the know that ignorance is the best defense against this thing, as it cannot affect anyone who doesn't know about it. Coincidentally, a race of Eldritch Abomination aliens mysteriously appeared nearby around the same time. But they don't like it if you ask too much about what happened.
  • The Elder Scrolls IV: Oblivion: "I have seen the Gates of Oblivion, beyond which no waking eye may see."
    • The Elder Scrolls has a daedric prince dedicated to this, called Hermaeus Mora. Appropiately, he's the only one of them who looks like an Eldritch Abomination. It also does a pretty god job of keeping this information from falling into mortal hands.
      • One in-game book describes a mage who tried to explore the realms of Oblivion. When he entered Hermaeus Mora's realm, a vast library, he became enamored with the knowledge and never left. His voice still whispers to the writer, each time more and more alien.
  • "There are things I need of you. Things you may not understand, and may not wish to do, but please, do not make the same mistakes I did [...] Human nature sealed my downfall. My name is Philip. If we are lucky, then by the time you receive this, I will be dead. If fate frowns, we all perish"
  • In The Reconstruction, Falitza allegedly destroyed her mind by "peering into the unknown". Subverted, though -- it's Obfuscating Insanity. She was so sick of being "little miss perfect" that she staged the whole thing to get thrown into Sanctifel.
  • In Dark Souls, the final part of Big Hat Logan's storyline if you rescue him and learn all of his sorceries has him going insane and becoming Hollowed while trying to decipher and duplicate the spells of Seath the Scaleless, the dragon progenitor of sorcery.

Web Comics

  • This Nodwick strip had entirely too much fun with this, as quoted above. The Thing Man Was Not Meant To Know was discovered by She Who Must Be Obeyed and taken back to The Lands That Know No Name! ("Let me know if we stumble upon any proper nouns in all this mess"), but it turned out to be completely ineffective (though apparently hilarious) when known by women...
  • Vaarsuvius of Order of the Stick regularly boasts about know secrets that would drive lesser minds mad.
    • MAD!!
  • In Sluggy Freelance, after assuming a more woman-like form, Aylee learns things that men, specifically, were not meant to know.
  • Dork Tower has "Lovecraft is... sharing that which man was not meant to know".

Web Original

  • The book "Incongruity" by best-selling horror author Michael Waite in the Whateley Universe. You're fine reading it, unless you happen to know that it is really The First Scroll of The Kellith, who is prophesied to wipe mankind off the face of the earth and re-populate the planet with the seed of the Great Old Ones. It also helps not to know that Michael Waite will become The Kellith.
    • Pretty much anything to do with the GOO. At least one person has marveled at the fact that Hekate's brain hasn't melted out of her head yet.
  • In SCP Foundation, the [DATA EXPUNGED] are covered up with [DATA EXPUNGED] to prevent making people [DATA EXPUNGED]
  • One of the many theories connected to the Slender Man is that the more you know about him, the more likely it is that you'll be next...

Western Animation

  • Parodied in The Tick (animation): "Let us not forget the lesson that we can learn from this, Arthur, that man was not meant to tamper with the four basic food groups."
  • An episode of Justice League Unlimited that featured time travel posited that no one must know how the universe was created. If you want to know, it's represented as a ball of light emanating from an enormous hand within a dark void, and since all those other gods exist...
    • In the comics, a Guardian of the Universe (specifically Krona) found out (with severe and unpleasant consequences) and so the rest of the Guardians wanted/needed to make sure it never happened again. (Details vary depending on when the specific telling of the story was written.)

May God help you.

  1. A special ability that lets a wizard see things as they are, for the low, low cost of never being able to forget it