Perception Filter: Difference between revisions

{{quote|"The technology involved in making something properly invisible is so mind-bogglingly complex that 999,999,999 times out of a billion it's simpler just to take the thing away and do without it... The 'Somebody Else's Problem field' is much simpler, more effective, and "can be run for over a hundred years on a single torch battery."|'''[[Douglas Adams]]''', ''[[The Hitchhiker's Guide to the Galaxy|Life, The Universe and Everything]]''}}

 

 

 

Very often used by witches in [[Fantasy]]. Power to avert everybody's eyes apparently is a must for them.

 

See also: [[Weirdness Censor]], [[Invisible to Normals]], [[The Nondescript]]. Compare [[Jedi Mind Trick]].

{{examples}}

== Anime and Manga ==

 

* Popped up, of all places, in a [[Mahjong]] game... specifically, in the anime ''[[Saki (manga)|Saki]]''. Touyoko Momoko, the 'star player' of Tsuruga Academy, has a special ability to 'disappear' by blending into the background. Depending on how attentive her opponents are, it may take her a while to disappear, but once she does, the rest of the players at the table simply ignore her, as well as her discarded tiles - allowing her to pull off some truly insidious gambits. It doesn't work on Nodoka once she's in the zone - she's just seeing the entire table like a PC-monitor, and there's no room for tricks like that in Online Mahjong.

* People notice Kagero Usui from ''[[Sayonara, Zetsubou-sensei]]'' only when his balding head is exposed. The reason is never explained.

* In ''[[Ghost in the Shell]]'', sufficently skilled hackers can essentially edit themselves out of people's vision, this trick is used in [[Stand Alone Complex]] by the [[Anti-Villain|Laughing Man]] {{spoiler|And The Major when she's impersonating him}}.

* In ''[[Mahou Sensei Negima]]'', {{spoiler|this is the power of Natsumi's pactio artifact}}.

 

== Comic Books ==

* In an ''[[Archie Comics]]'' story, Jughead justifies his drab, downbeat style of dress to Veronica by showing her that it renders him ''de facto'' invisible to teachers, canvassers for charity, and such, in contrast to her bold, stylish fashions. At the end of the story, an impressed Veronica likewise starts dressing not to be seen.

* In ''[[The Ballad of Halo Jones]]'', Glyph had their sex changed so often they ended up with a gender-neutral body and this ability. While they find it much easier to get whatever they want (being able to bypass a checkout counter and so on), they are ''very'' lonely since they can't turn off this 'power'.

* One of the people who was [[Doctor Fate]] for a while, Inza Nelson, would switch between her civilian identity and Doctor Fate ''right in front of people,'' and got away with it by mind-controlling everyone in the area for a split second to not notice.

 

* It's used to explain how the [[Celebrity Paradox]] can exist in ''[[Rich's Comix Blog|A Time To Kill]]''. The Tenth Doctor tells Donna that "the combination of sounds, vowels, consonants, cadence" in [[James Bond]]'s standard introduction ("[[Bond James Bond]].") acts as an audio perception filter, meaning that Bond can introduce himself to people and they won't remember details about him, including the fact that he's the living embodiment of what ''should'' be a fictional character. Then, to demonstrate, the Doctor uses the line on Donna, and she instantly forgets everything he told her about Bond.

 

== Film ==

* In the ''[[Lord Darcy]]'' books "invisibility" means that people just instinctively avoid looking where you are. They can still see you in a mirror, though. In one of the books a character asks "suppose they made the mirror invisible as well?" and is told they ''could'', but you have to look ''somewhere'', and the more places your eyes slide away from, the more likely you are to become suspicious.

* As well as ''[[Discworld]]'' witches, who get covered above under fantasy, Susan Sto Helit can "fade into the foreground". This seems to be a theme in Discworld: Pratchett maintains that if something is utterly outlandish and impossible enough (for example, a donkey standing on top of a very very high pole), humans will go out of their way to not notice it or subconsciously pretend it doesn't exist. Animals, who do not have the advanced mental perception filters humans have that enable them to see exactly what isn't there and not see what is, do not fall under the blanket of this trope.

** While still a student Lord Vetinari practiced standing so still that no one saw him. It worked.

* The [[Somebody Else's Problem|SEP]] field in ''[[The Hitchhiker's Guide to the Galaxy]]'' works like this.

*** And at one point in the novel {{spoiler|in a total subversion, he discovers that if he gets angry enough, his power can reverse itself, making him ''the only thing'' that the target is able to focus on, to the exclusion of all other conscious thought. As portrayed in the book, this is ''horrifying'' to the person experiencing it.}}

** It eventually became listed among the "officially recognized" psychic powers in Niven's "Known Universe" and was named "Plateau Eyes," based on the fact that the original novel was set on the colony world, Plateau.

** As does The Leaky Cauldron and the door to St Mungos (when it's not disguised as an abandoned department store) and presumably most wizarding establishments.

** It's stated in GoF that the Wizards have spells that make Muggles remember stuff they had to do when they enter the AoE of the spell.

* In the ''[[Wheel of Time]]'' books Grey Men are people who have given their souls to the [[Satan|Dark One]], and as a result always blend into their surroundings. They are used as assassins in public areas, quite capable of walking right up to someone and stabbing them without ever being noticed. They are quite cleverly dealt with in the textual medium by casual insertion into a descriptive passage, so that the reader is likely to ignore them as well as the characters.

 

 

* In ''[[Doctor Who]]'' this is called a "[[Trope Namer|Perception Filter]]". It's used to explain why the TARDIS can go unnoticed even though it's [[Shapeshifter Mode Lock|mode-locked]] in its anachronistic police box form (with some help from humanity's natural [[Weirdness Censor]], of course). A number of other objects have had this applied to them, such as the pavement-stone-lift used by [[Torchwood]]'s Cardiff branch.

** The Chameleon Arch, a [[Gadget Watch]] a Time Lord can store their consciousness in, has one to prevent the newly-created disguise personality from opening it. They'll keep it with them, but will assume it's broken unless their attention is specifically drawn to it.

** In the 2007 finale, the Doctor extends the effect to the TARDIS keys he and his companions carry, allowing them to avoid detection after Mr Saxon has them declared public enemies.

''[cut to longing looks from both Martha and Jack]'' }}

** In "The Vampires of Venice", the titular vampires only look human due to a complicated perception filter disguising their true form (though it doesn't hide the teeth).

* In both ''[[Vampire: The Masquerade]]'' and ''[[Vampire: The Requiem]]'', the vampiric power Obfuscate works this way.

* ''[[Legend of the Five Rings]]'' has an Air Spell that does this.

* In ''[[Mage: The Ascension]]'', Mages can buy this ability as the background "Arcane", which means people tend to forget them right away after seeing them.

 

== Videogames ==

* Koishi Komeiji of ''[[Touhou Project]]'' uses her power over the subconscious mind in this way to move about unnoticed by others.

* The Stone Mask in ''[[The Legend of Zelda: Majora's Mask]]'' has this effect, making the player "inconspicuous as a stone." Link can't see an NPC wearing the mask without the help of the Lens of Truth.

 

== Web Original ==