Awful Truth

""What I'm about to tell you, you might not want to know. Even so, you absolutely must hear it. [...] Given who you are and how you've lived, what I have to say may tear at your hearts...""

-, Mother 3

You Don't Want to Know what the Awful Truth is. Now, I know you really, really want an answer, but trust me, it'd be really, really bad if you knew who you really are, who I really am, what hidden or forgotten powers you have, what the world is really like, and especially who your real father is. At best, you'd completely Freak Out. At worst, you'd Go Mad From the Revelation! Just trust me, young one -- ignorance is bliss.

Convenient excuse to keep vital information from the hero(es). Alternatively, a mocking cry by the jaded Anti-Hero to illustrate his belief that the main hero is too innocent/pampered/naive to be trusted with the truth about the mission or about people that he's grown to trust or care about.

Compare You Are Not Ready and Forbidden Fruit. Contrast You Didn't Ask. If they're being obnoxious about it, it's Figure It Out Yourself. See also These Are Things Man Was Not Meant to Know for when you really shouldn't know. Can also be a case of You Do NOT Want to Know. Compare Heel Realization, which is an awful truth, but not one anyone else kept from you. Often invokes Schmuck Bait.

'''As this is a Spoiler Trope, expect plenty of unmarked spoilers. Read with discretion.'''

Anime & Manga

 * Himeno Awayuki of Prétear was told that she "doesn't need to know" the Backstory, but forced the Leafe Knights to reveal it anyway -- specifically, that their enemy is the previous Pretear, who turned evil because of her unrequited love for Hayate, and that she herself may end up turning evil as well. Cue Heroic BSOD. In the anime version, the consequences were even worse.
 * In the manga, her stepmother unleashes another one on Himeno: Himeno's late mother died because her frail body couldn't handle the strain of pregnancy and childbirth. In other words, Himeno killed her own mother.
 * In the manga version of Chrono Crusade, part of what inspires Aion's Evil Plan is the Awful Truth he found out about his origins (that is, that the demons are really aliens, and the current Hive Queen was a human woman pregnant with twins (Chrono and Aion) before she was turned into a demon). He also goes to great lengths to hide the truth from Chrono, saying he "doesn't need to know"--but Chrono finds out in the end and takes it rather well, actually.
 * In Detective Conan, Ai keeps insisting to Conan
 * In Fullmetal Alchemist, Dr. Marco refuses to tell Ed how the philosophers stones are made.
 * Far worse in the manga and second anime. Along with the fact that  the government's true intentions are so dark that even the
 * In Naruto, the reason why the villagers hate Naruto is that he's the can of the Nine-Tailed Demon Fox which killed many of them and destroyed a good part of the Leaf Village.
 * Sasuke was far happier thinking . He was a lot saner then, too.
 * In Bokurano, the main characters were originally told what was going on was a game to ensure they would fight in and against giant mecha. The prospect of defeating the enemy was a lot easier when they didn't know doing so would . And when they thought the enemies were . They were, however, told what failure meant, though the general public was mostly out of the loop.
 * Anyone who wants to become a Magical Girl in Puella Magi Madoka Magica must know one thing:.
 * Two things, as of Episode 8. . Just in case that wasn't horrifying enough,
 * And just to make things even worse? . This basically means that.
 * To top it all off, the reason is doing all of this? 
 * Madoka eventually provides an out of sorts for this by
 * A Tengen Toppa Gurren Lagann example: Continued use of Spiral Power will eventually lead to an event called the Spiral Nemisis, which will give birth to a super-galaxy that will rip the universe apart.
 * Inuyasha: Just as Sesshoumaru's finally getting used to the idea that Tetsusaiga was meant for Inuyasha and Tenseiga was meant for him, he learns the truth:  Sesshoumaru takes the news badly, concluding it's proof he was the outcast son and that his father was training Inuyasha to kill him. Even Inuyasha and his friends think this was far too cruel.
 * In The Secret Agreement, Kyuusai reveals to Yuuichi that he is from a powerful clan that steals other people's life force, and that neither he nor his boyfriend actually love each other, it's just an implanted delusion between predator and prey that makes it easier for Yuuichi to steal Iori's life. Yuuichi is horrified.

Comic Books

 * In the TV series, Connor had already regained the memories of his real life, but in Angel: After the Fall, his personal side effect of being in Hell is remembering everything. EVERYTHING, in crystal clarity. As in, vividly remembering having sex with a woman at the same time you remember her changing your diapers. Not to mention betrayal of a loving father.
 * In Alan Moore's run on Swamp Thing, Abby goes into a Heroic BSOD after realizing that  This is exactly as squicky as it sounds.
 * And well before that, at the start of Alan Moore's run, Swamp Thing found out that he'd never been Alec Holland, just a mass of intelligent vegetation with Holland's memories. He didn't take it well.
 * The conclusion of Watchmen:

Film
"Col. Jessep: You want answers?
 * A large part of the premise of The Matrix.
 * And thanks to the technology available, they can actually unlearn the awful truth.
 * Most famously invoked by Jack Nicholson in A Few Good Men:

Kaffee: I want the truth!

Col. Jessep: You can't handle the truth!"

"Ash Correll: Tell us the truth.
 * And parodied by Sideshow Bob in The Simpsons ("No truth handler you! Pah -- I deride your truth-handling abilities!")
 * Also on Third Rock: "You want the truth? You want the truth? Well, I can't handle the truth!"
 * NSA agent Patellis' excuse for their secrecy in The Forgotten.

Agent Patellis: The truth? The goddamn truth won't fit in your brain."

"K: There's always an alien battle cruiser, or a Corellian death ray, or an intergalactic plague intended to wipe out life on this miserable little planet. The only way these people can get on with their happy lives is that they do. Not. Know about it!"
 * Men in Black II, Agent J asks Agent K why he didn't tell him that his new girlfriend was the key to stopping an interstellar war and had to leave. K's response: "Would you have let her go?"
 * On a larger scale, this was part of the point of the Masquerade in the first place. Something about constant threat of The End of the World As We Know It being a bit much for most people to handle.
 * Probably nothing to do with this whole article, but one of the Men In Black video games had a weapon called "Awful Truth."
 * And in the original movie there was this gem from K:


 * In the Korean movie Old Boy, Dae-su is kidnapped, imprisoned for 15 years, and then released with no explanation. After finding and confronting the man responsible, Dae-su finds out the Awful Truth isn't "Why he was imprisoned" but "Why he was released." He goes mad from the revelation and.

Literature
"Qilue: If you doubt me, curl yourself around the Ladystone to sleep tonight, pray to Eilistraee for judgment upon me, and learn your answer. [...] Yes, do that. [...] Learn the truth.
 * Harry Potter: In Harry Potter, when Harry asks Dumbledore why Voldemort wanted to kill him in the first place, Dumbledore's response is more or less that Harry is not yet ready to hear the Awful Truth, but at least makes clear that he has the intentions to tell him some day. Intentions being the key word here, as Dumbledore puts this off until the fifth book and only tells Harry then because  This isn't the only instance, but probably the most significant as much of the plot revolves around adults trying to protect Harry from the awful truth.
 * This also plays a rather large role in the third book. First with Cornelius Fudge's insistence that no one tell Harry that Sirius Black is out to get them because it might scare him. Proving that not all adults are complete idiots, Mr. Weasley planned on telling Harry anyway, telling Harry to be careful and warns him not to go looking for Black. But he also falls into this trope by refusing to answer when Harry asks why would he be stupid enough to looking for someone who wants to kill him. Harry finds out anyway, but proves Mr. Weasley's fears correct because the Awful Truth in fact makes him want to kill Black.
 * The Awful Truth is in fact so awful that Dumbledore only reveals it in fragments; first, at the end of Order Of The Phoenix, Then, in Harry Potter, he tells Harry that   Finally, in Harry Potter, Harry learns that he Of course,, but as he didn't know that, it was still pretty Awful.
 * Of course, this was all necessary for Dumbledore's plan to work. In the first place, he wasn't even sure that . But even if he had hard evidence that, he couldn't have told him, because if Harry didn't think for everyone in the castle? So in this case, it was more revealing the Awful Truth while hiding the Wonderful Truth that accompanied it.
 * The Prayer Of Miriam Cohen by Rudyard Kipling unfolds this trope. Not in very flattering way, though.
 * In Catherine Asaro's The Misted Cliffs Backstory, Dancer left her husband with her son to return to her abusive father, who battered both her and her son, Cobalt. When he was grown, Cobalt rescued his father and found him to be a loving and affectionate man, but his mother refuses to explain. At the end of the book, Dancer explains to her son's wife, Mel,.
 * In the sequel The Dawn Star, his dying grandfather tells Cobalt a secret. Throughout the book, Mel is terrified that the grandfather guessed and told him. At the end, Cobalt reveals that he had said that.
 * Sort of inverted in Silverfall: mentor desperately wishes her [in]subordinate could understand.

Thalaera: Will I be maimed?

Qilue: Hurt, perhaps; maimed, no.

Thalaera: Hurt?

Qilue: Truths have sharp edges. Learning the truth often hurts."

"'There is not enough room in your head to under­stand what I could tell you. I have seen the forces that really hold this universe together, and it isn't your Emperor. All you Imperial vermin devote your lives to crushing the spirits of mankind until not one man or woman could survive knowing the truth.'"
 * Overlapped with You Do NOT Want to Know in the X Wing Series. When Donos found out, his first impulse, which he acted on, was to try to kill Lara. And anyone else in the way.
 * In Oedipus Rex the title character is warned by the soothsayer Tiresias that he really doesn't want to know the truth, but tragic pride gives Oedipus the persistence to find out.
 * In The Dresden Files, this is played in several different ways. First, anytime Harry has to let people in on the Masquerade, he tells them straight up that they're probably never going to sleep well again. Also, when Harry confronts his mentor, Ebenezer, and Ebenezer tells Harry
 * Notably used with Murphy, as that's what led to his realization that some times people need to be told the truth. For the first three books, she's wary of him because he's so ambiguous all the time and nearly gets herself killed on a number of occasions-- not to mention that she's always almost-arresting Harry. He finally explains everything to her in Summer Knight, which leads to a much closer friendship and a couple levels of badass on Murphy's part.
 * German philosopher Oswald Spengler's non-fiction book The Decline of the West is full of them and culminates in "optimism is cowardice."
 * In the Warhammer 40000 book Grey Knights, renegade inquisitor Valinov seems to refer to Chaos as the Awful Truth:


 * The Grey Knights themselves are an example. Any average Imperial citizen who learns of their existence is killed out of hand. Even Space Marines who learn about the Knights without authorization are mind-scrubbed to remove the truth.
 * In the Vorkosigan Saga novel The Warrior's Apprentice, Elena searches for her long lost mother. She finally learns her mother's identity  Likewise, the main plot of The Vor Game is triggered by Gregor learning that his late father was a rapist, a murderer and generally a Complete Monster.
 * In the Ender's Game book Shadow of the Hegemon, Bean learns from a posthumous letter the Awful Truth about his own birth: That his increased intellect has a side effect in that
 * Speaking of Ender's Game, the fact that Ender was is a prime example.
 * In the Spellsinger spinoff, Son of Spellsinger, the Grand Veritable is a magical, sentient lie detector that can not stop declaring the truth. Fun ensues as it wrecks relationships across the Bellwoods.
 * In Ursula K. Le Guin's short story "The Ones Who Walk Away from Omelas", a child is brutally tortured to maintain the prosperity of the eponymous city. At some point in their lives every citizen of Omelas sees the child and learns of the connection between the child's suffering and the city's wellbeing. The title refers to the people who can't live with the Awful Truth anymore and leave Omelas forever.
 * Even aside from the substantial amount of philosophical musings on this trope (where it is nearly referenced by name), Sergey Lukyanenko's Night Watch has more than its fair share of examples. Early on, for instance, the protagonist Anton runs into a seemingly random cursed woman on the metro who he tries to help out. Soon, the events at the beginning of the plot which seemed to be important are discarded to focus on her.

Live Action TV
"Director Sterling: "Information about this has always been on a 'need to know' basis."
 * The 80's revival of The Twilight Zone did an episode titled "The Need To Know," in which this trope is deployed quite literally; a man returns to his small town bearing the Truth of Existence, a short phrase which drives anyone who hears it instantly insane.
 * Battlestar Galactica plays this straight when Kara attempts to figure out  and when, in the Season 3 finale, Colonel Tigh keeps trying to figure out what the Terrible Ticking is all about. Turns out, they did not want to know. They got better. Averted when Kara finally discovers the meaning of the prophecy that she will "lead them all to their end."
 * Dexter is essentially a Thirty Awful Truth Pileup, both for the eponymous character and those close to him. In Season 1 he discovers that the reason he is being singled out by the Icetruck Killer is that the two are brothers. Which wouldn't be terrible in and of itself, but it comes with the realization that Harry Morgan didn't quite tell the whole truth and nothing but the truth: Dexter watched his mother die. Also, Harry's a liar..
 * Ashes to Ashes: The big reveal(s) at the end of the programme could qualify as The Awful Truth to the character(s) it applies to.
 * King Uther's refusal to tell Arthur the truth about his magical birth and the death of his mother(s) in Merlin. Arthur seemed to find out in the episode "Sins of the Father", but came to believe Merlin's statement that Morgause lied to him completely instead of only partially.
 * The eponymous event in The Event is apparently a truth so awful that the CIA director didn't want to tell the president, much less the viewers.

President Martinez: "I'm the president. I need to know!""


 * This is a major plot point of The X-Files. The tagline for the show is "the truth is out there", and Mulder spends nearly a decade trying to uncover it. When he does, he finds out why it's been kept hidden from society for sixty years. He was reluctant to even tell Scully, as the Truth is
 * Subverted earlier with the truth about his sister, Samantha. The quest to find his sister was the reason Mulder got started on the X-Files, and a when not trying to find out The Truth, he is trying to find out what happened to her. After an extremely confusing plotline, we find out . It is classified as an awful truth, but Mulder is simply satisfied to finally know what happened to her. The episode is aptly named "Closure", and when Scully asks him at the end of the episode how he is dealing with it, he replies "I'm free."
 * In the Doctor Who episode "The Beast Below" all subjects of Starship UK are required to "vote" when they turn 16 and every five years thereafter. The are taken to a room were there shown a video then allowed to either protest, or forgot that . Everyone seems to choose the mindwipe, and the few that do protest are fed to the star whale.
 * Poor, poor Phillip of Kamen Rider Double. First he found out that his family is really the mafia providing people the Transformation Trinkets needed to transform into the Monsters of the Week, then he found out that he's Dead All Along.
 * Not to mention Terui Ryu, who finds out that the person who gave him the gear needed for him to be Kamen Rider Accel also gave the Weather Memory to Isaka, the man who killed his family. Then he finds out why she did that.

Music Videos

 * The music video for the song "Just" by Radiohead. A man lies down in the middle of the street, refusing to get up or tell anyone why, because if they knew, they would to the same.

Newspaper Comics
"Jason: How'd you know where to press?
 * Played with and subverted by FoxTrot. Peter has just broken Jason's incredibly difficult-to-build lunar module model, due to practicing baseball in Jason's room. Jason is rightly pissed, and tells Peter that in a day, he will visit an awful punishment on Peter, refusing to tell him what it is. For the next four strips, Peter runs and hides in the backyard, is forced to eat sticks and leaves, spends the day lying in dog crap, and is grounded, all while trying to avoid Jason. When the time is up, he goes to Jason and laughs about how Jason never got him, then goes bug-eyed when he realizes what happened.
 * And another: Jason gets a Darth Vader mask stuck on his head. After all other attempts at removing it fail, Roger of all people saves the day by showing him where to press on it.

Roger: I used to wear one when the movies came out.

Jason: You mean, you were a fan before I was?

Roger: Search your feelings, you know it to be true.

Jason: NOOOOOOOOOOOOOOOOOOOOOO!!!!!!!!!"

Tabletop Games

 * The fact that the New World of Darkness is, well, a World of Darkness is a secret desperately kept from ordinary humans in the eponymous setting. It's an odd example, though, because the books state that a large part of why all the separate Masquerades are in place is for self-preservation: if all of humanity knew the truth, humanity would fight and the supernaturals would lose. The Hunters cause enough problems as it is.
 * There is also the equally terrifying possibility that humanity would fight the supernaturals and no-one would win. What would inherit the Earth in that circumstance doesn't really bear thinking about.
 * Battle Tech: As the Inner Sphere is getting mauled by the technologically superior Clans some believe that the descendants of General Kerensky's Star League Defense Forces (who fled into unknown space centuries ago to avoid getting caught in a civil war and being forced to fight those they swore to protect) will come back to assist them in their darkest hour. A certain mercenary leader... refutes this theory.


 * Warhammer 40000. Hoo boy... let's just say that the Imperium has a good reason for its proverb "Ignorance is a virtue."
 * Chaos is the prime example of the Awful Truth. The Inquisition is quite willing to sterilize and relocate anyone who might have learned about it to forced labor camps for the rest of their lives. If this isn't practical, the Inquisition will just kill everyone. This policy can be applied to entire worlds with billions of people on them, and is still considered the humane solution compared to what might happen otherwise.

Video Games
"Wakka: We weren't hiding it!
 * Experienced Shell Shocked Senior Auron from Final Fantasy X intentionally keeps the truth regarding the summoners' journey for the Final Aeon, that it is, from the the rest of the characters. When they finally figure it out on their own and demand an explanation from Auron about this, he simply responds, "Would that have stopped you?''
 * The less-obvious reasoning behind this masquerade is that Auron simply saying  wouldn't be enough to change anything, and would more likely result in the party accepting the situation. By only revealing certain key bits of information as the journey continued, Auron was able to direct them on the path he tried to take before:  . Almost Magnificent Bastard levels, when you think about it.
 * Besides, indiscreet revelations of the Awful Truth behind Spira can backfire spectacularly. Look at what happened to Seymour.
 * He actually outright states that very early on but it doesn't take because he doesn't explain the story behind it.
 * Before this, the entire rest the party takes quite a long time to reveal to Tidus that Yuna's journey as a summoner is intended to end with Understandably, Tidus doesn't take it well.

Lulu: It was just... too hard to say."

"Alex Mercer: I looked for the truth. Found it. Didn't like it. Wish to hell I could forget it."
 * A major component of Xenosaga.
 * Kevin  He died in Shion's arms and she was haunted by the memory for years.
 * The fit of agony and rage Shion felt upon her parents' deaths is what  Febronia knew this but spent the better part of 3 games slowly guiding her to where she could retrieve this repressed trauma.
 * From the previous page quote, Alex Mercer spends the majority of the game Prototype trying to figure out who was responsible for the viral outbreak which destroyed his memory..


 * In In Famous, Cole gradually grows to hate the Big Bad, Kessler, as Kessler is both responsible for the event that gave Cole superpowers at the cost of thousands of innocent lives, and eventually  all the while spouting rhetoric about how Cole needs to learn what an awful place the world really is instead of pretending it's any better, never offering even a cursory explanation for why he's doing any of it. In the end, just before Kessler dies from wounds Cole inflicts, Kessler reveals via telepathy that
 * Turning the evil ending into a case of Gone Horribly Right.
 * Metal Gear Solid 4 pulls a complicated Awful Truth on the protagonist. Solid Snake has started to show indications of accelerated aging; by the time the game starts, he's going on forty-one years old, and looks older than his parents (who should be over eighty by then). Otacon explains that it seems like a classic case of Werner's Syndrome, except the tests for the condition say that Snake doesn't have it. They speculate that it's because Snake isn't "normal," meaning that there must have been some fluke in the cloning process that created him, possibly exacerbated by the nanomachine-based artificial virus he was injected with to assassinate certain people by coming into contact with them. In fact, his brother Liquid even suggested as much, saying that the problem arises from the genetic sample that created them being taken when Big Boss was old himself, in his fifties. When Snake finally finds someone who can figure out what's going on, the truth is much worse than any of the speculation: The second problem is solved   but the first problem is most assuredly not, and the only reason we don't watch   is because the ending fades to black instead of fast-forwarding six months.
 * Mass Effect pulls some good ones. First, the set-up; all spacefaring races get into space by use of Element Zero, which, when hit with electricity, alters the mass of matter temporarily (the eponymous mass effect.) Interstellar travel is based on the mass relays, giant mass-effect devices left behind by Precursors who vanished fifty-thousand years ago.
 * Mass Effect:
 * Mass Effect 2:
 * Mass Effect 3:
 * In the final chapter of Mother 3,.
 * Hey, Ange? You know how you're pretty sure that your Ax Crazy aunt killed your beloved parents and brother? Well, it turns out Hope that cheers you up a little!
 * In Silent Hill 2, after barely making it to the hotel where he and his deceased wife spent so much loving tie together, James finally realizes that.
 * Worse yet,.
 * Subverted in the first Ace Attorney game near the end of case four:
 * In Cross Channel, this is how . The awful part wasn't the fact that.
 * In Star Wars: Knights of the Old Republic, the Jedi Council prevent the other party members -- and the player character him/herself from realizing that s/he is.
 * Corpse Party: is already in bad shape from ... Then . We later find out that it was only.
 * In Star Wars: Knights of the Old Republic, the Jedi Council prevent the other party members -- and the player character him/herself from realizing that s/he is.
 * Corpse Party: is already in bad shape from ... Then . We later find out that it was only.

Webcomics
"Breya: I... I really want to know, but I think I'm afraid to ask.
 * Schlock Mercenary hangs common sense on it:

Tagon: That means you don't really want to know."


 * Girl Genius, when Agatha discovers her mother Lucrezia was . Bonus points for off-handed delivery. Later Agatha herself supplies a few missed memos to an impostor pretending to be her. Right after the only scene when Zola acted nice, at that.
 * Chapter 31 of Gunnerkrigg Court might as well be called 'A Delightful Load of Awful Truths for Annie and Renard', because guess what, Renard?  And guess what Annie?   And when Annie runs to the forest, she learns that.
 * In Cyanide and Happiness: it's not the tooth fairy!
 * A side story in Jack  shows a guy in apparently his dream life: a great apartment, nothing to do but play games, and endless, tailor-made sexual partners. Odd things keep happening and he is driven to find out that
 * Worse still,

Web Original

 * Linkara's trademark Magic Gun is Powered By a Forsaken Child.

Western Animation

 * In The Venture Brothers, there are multiple cases of this:
 * Hank discovers that Fortunately, Sphinx is right next door with the mindwipe machine!
 * The identity of Hank and Dean's mom is strongly implied to be this.
 * Triana has a portal to an extradimensional realm in her bedroom closet, and gets repeatedly mindwiped by her father every time she forgets.
 * Two-Ton 21
 * Avatar: The Last Airbender: Well, there's no point in the characters defeating the Fire Nation before Sozin's Comet since they basically lost the war to them already, right? Cue Zuko informing the Gaang that
 * Not just genocide of the people; the plan was to send a wave of fire over the entire, continent. People, plants, animals, buildings... "scorched Earth policy" taken to an utterly terrifying level.

Real Life

 * YOUR PARENTS HAD SEX.
 * NNNNNNNNNOOOOOOOOOOOOOOOOOO!
 * AND YOUR GRANDPARENTS. 
 * MY EYES! MY POOR VIRGIN EYES!
 * SEARCH YOUR VHS TAPES, YOU KNOW IT TO BE TRUE!
 * People have known and admitted to the issue of bullying and have been hard pressed to stop it for years. Yet when bullying does occur in front of their faces...it is quite often shrugged off as "natural".
 * On the Straight Dope forum, several members shared stories of how, when they were children, they'd been told that their mysteriously disappeared pets had been "sent to live on a farm." Cue the inevitable post that went along these lines: "That's a coincidence, because when I was little, I had a dog that was sent to live on a farm.... oh ^#@$% I need to call my parents NOW."
 * Neal Boortz is the self proclaimed "High Priest of the Church of the Painful Truth".
 * Quite possibly apocryphal: the school of Pythagoras was so shocked to discover that the square root of 2 is an irrational number (i.e. cannot be expressed as fractions) that they kept the knowledge a closely guarded secret, and people who leaked it were punished by death.
 * The word Soccer...CAME FROM ENGLAND!
 * The Atheist Experience deconstructed this when a caller asked "What's wrong with a comfortable delusion" by arguing that the trauma isn't caused by finding out the truth, but by discovering you were lied to. How many of these examples would have turned out better if the people telling the lies had just told the truth in the first place?
 * Chances are, you are more likely to be raped by someone you know than a total stranger. 38% of the time it's going to be a friend, someone you already know and trust. There's an also 4-out-of-10 chance that you'll be raped in your home than anywhere else. And guess what? 15 out of 16 rapists will walk free.
 * Factoring in unreported rapes?
 * One reason those who are against corporal punishment give for their position give for their position is that supporting corporal punishment enables child abuse. Unfortunately, some actual methods of corporal punishment do carry a risk of serious harm, such as the belt, which is liable to cause bruising and, if the buckle hits the child, actually break the skin. Also, it has been proven that causing physical harm to another person increases the production of endorphins and decreasing the quality of the person's judgement, making it less likely that they'll remember that they swore that they would never do anything more severe than whatever they're doing to the child as well as giving the person a "high", making it more likely that s/he'll escalate the violent behavior in order to maintain or increase this "high".