Sudden Question: (i dare you to name one western cartoon that dealt with Quantum Mechanics, Time Travel, Sexual Identity, Psychology, Nature of Existence and Human Souls, Natural Disasters, Cruelty of War, Discrimination, Bio-terrorism, Detailed Futuristic Technology .. etc etc) .. NEVER any of these topics been discussed in any western cartoon and probably will never be.
Very few western cartoons are mature (some Batman movies are good and Avatar the Last Air Bender is wonderful).. but almost 99% percent of western cartoons are made for kids and are far from mature (either crude humor or brainless comedy stuff) .. there might be some European cartoons that have mature/grown-up themes but they are mostly rare and obscure to say the least.
As for anime .. of course nobody is talking about mature=fanservice (nudity and sexual scenes) and gore .. although they are necessary sometimes to set the mature tone .. and as long as they aren't excessive or crude they enhance the experience (Best example would be Berserk).. yeah there are many cheap animes that only focus on sexual themes, brainless humor or repetitive hot blooded fights and that kind of stuff .. but as much as there are cheap animes that does that there are numerous animes that have mature stories/topics/themes that western cartoons wouldn't even dare discuss or approach in 50 years.
((Examples))
--Mature TV animes that depend on fully developed and deep themes--
-Monster
-Ghost in the Shell
-Darker Than Black
-Ghost Hound
-Gankutsuou
-Guin Saga
-Himitsu
-Mouryou No Hako
-Planetes
-Natsume Yuujinchou
-Paranoia Agent
-Patlabor
-RD Sennou Chosashitsu
-Seirei No Moribito
-Evangelion
-Tokyo Magnitude 8.0
-Twelve Kingdoms
-Mushishi
-Fantastic Children
-Serial Experiments Lain
-Baccano!
-Casshern Sins
-Death Note
-Full Metal Alchemist
-Clannad. Orphen
-Cowboy Bebop
-Samurai Champloo
-Kanon
-Ergo Proxy
-Eureka Seven
-Fruits Basket
-Flag
-Gundam 08th Team
-Gungrave
-Noein
-Zone of Enders: Dolores
-Yugo: The Negotiator
-Crest And Banner of the Stars
-Legend of Galactic Hereos
-Starship Operators
-Infinite Ryvius
-Eden of East
-House of Five Leaves
-The Garden of Sinners
-Black Lagoon
-Eve no Jikan
-Noir
-Sora no Oto
-Texhnolyze
-Gilgamesh
-Wolf's Rain
-Sky Crawlers
-Michiko to Hatchin
-Witch Hunter Robin
-Gunslinger Girl
-Le Chevalier D`Eon
-5cm Per Second
-Ai Monogatari: 9 Love Stories
-Battle Angel Alita
-Bonen no Xamdou
-Toward the Terra
-Armed Librarians - The Book of Bantorra
-Revolutionary Girl Utena
-Ayakashi: Japanese Classic Horror
-Mononoke
-Kaiba
-Red Garden
-Rainbow
-Senkou no Night Raid
-True Tears
-White Album
-Cross Game
-Giant Killing
-FREEDOM
--Mature TV animes that do use blood, gore and sexual themes "correctly"--
-Aoi Bungaku
-Elfen Lied
-Berserk
-Basilisk
-Blue Gender
-Speed Grapher
-Shigurui: Death Frenzy
-The Portrait of Cosette
-Requiem from the Darkness
-Ninja Scroll
(PLUS Numerous Anime Full-Feature Movies that rival Hollywood movies .. Grave of Fire Flies, Patlabor WXIII, The Girl Who Lept Through Time, Paprika, Princess Mononoke, Akira, The Wings of Honneamise, Perfect Blue -recently ripped off by hollywood-, Vampire Hunter : Bloodlust, Spirited Away, .. etc etc etc .. just to name few)
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Sorry guys .. but people who really think that anime is all about hot blooded dudes fighting, nudity, gore and titties .. you are dead wrong and obviously know nothing about anime .. at best the ratio of good show to crappy ones is 50/50 .. and not only that .. but that 50% of good mature anime includes numerous show (in hundreds) and encompass all sorts of topics and mature themes that are never discussed in cartoon and probably will never be like i said above once (name one western cartoon that dealt with Quantum Mechanics, Time Travel, Sexual Identity, Psychology, Nature of Existence and Human Souls, Natural Disasters, Cruelty of War, Discrimination, Bio-terrorism, Detailed Futuristic Technology .. etc etc) .. NEVER any of these topics been discussed in any western cartoon and probably will never be .. mature western cartoons my ass.
The Boondocks
Family Guy
Futurama
Afro samurai
Samurai Jack
Batman
Young Justice
Justice leauge
All these american/western cartoon might use crude humor or approach some decent topics .. but never in the way the animes above do and not with the same fidelity and quality in both narration and art .. far from it.
Heck .. if you want to compare anime to a western mediums you would have to compare it to (Hollywood Movies+Western Cartoons+Western Novels+TV shows) combined to be fair ... actually many animes are inspired by mature western novels (like "Ghost in the Shell" is inspired by the Neruomancer Sci-Fi novel) ... and "Legend of Galactic Hereos" single-handedly outdoes all western TV shows about sci-fi space-operas .. so comparing the totally shallow western cartoons to anime is laughable and pathetic really .. so please learn about the subject you are talking about before spouting nonsense XD