Religion Is Wrong

Isaac Asimov once said that most Science Fiction is written by atheists. There are a number of notable exceptions, and it might not be literally true, but Sci Fi probably has more atheist authors than other genres do. A lot of these writers insert this personal outlook into the story. Sometimes they just portray atheists as good and rationally thinking people. Sometimes they go further.

For instance, say we have a Crystal Dragon Jesus cult which has something material as the object of worship. Let it be the Church of the Moon Goddess. Then we invent spaceships, fly to the moon and see that it's just a piece of lifeless rock and the goddess is absent. Or we have a Goddess of Harvest living in the mountain and then find out that it's just a semi-sentient weather control machine.

That's the trope: Setting up a proof that atheism is right. May lead to Outgrown Such Silly Superstitions, No Such Thing as Space Jesus, etc. Religious characters will react to it either negatively ("My entire faith is a liiie!" perhaps, or "I reject your reality and substitute my own,") or unnaturally positively ("Oh, God's not real? Welp, that's thirty years of time wasted. Do atheists have cookouts?"), leading us to Belief Makes You Stupid and even, confusingly, some instances of Hollywood Atheist.

Notice that most examples come up with some kind of masquerade around a fictional religion, rather than talking about a real-world religion. That's because of the complicated, baroque cease fire fire negotiated between atheists and religious scholars called Non-overlapping magisteria. Briefly, this means that modern religions are non-falsifiable: They can't be proven wrong, but, in turn, they can't make any claims that can be proven wrong.

Compare Scam Religion, Unwanted False Faith and The Presents Were Never From Santa. Contrast Religion Is Right. For a musical version, this trope is also a goldmine of Religion Rant Song material. For an emotional, rather than scientifical, denounce see There Is No God.

Anime And Manga

 * This seems to be the case in the Death Note universe. At the beginning of the series, the Shinigami Ryuk tells Light Yagami that anyone who uses the titular notebook can "neither go to heaven or hell", but at the very end,  we see a flashback were Light deduces that this simply means that there is no afterlife at all. Also, Word of God has apparently stated at least once that there are no gods in the manga's universe, aside from the shinigami. This is at least the case in the manga; the anime series is much more ambiguous on the question of God and the afterlife.

Literature

 * In His Dark Materials, God exists, but Magisterium is wrong and corrupt, they must die, their churches must be destroyed and characters will team up with anything, be it good or evil, to fulfill it. Priests are depicted as being nothing but Card Carrying Villains. Word of God was that  is god, the magisteriums god just stole credit for it in an attempt to grab power.
 * H.P. Lovecraft was an atheist, and this made its way into his stories. He imagined a universe where humanity and religion are essentially just annoyances to gigantic monsters from outer space who we foolishly perceive as gods. Interestingly, he mixes it with a heavy dose of Science Is Bad and/or Science Is Wrong at the same time, so it's more like Any Human Attempt To Understand The Universe Is Wrong. And liable to get you eaten.
 * Bob Shaw's The Ragged Astronauts features twin planets and the cult claiming that all people reincarnate cycle between these two planets eternally. Then the characters make an expedition to the second planet. You can guess whether they find people there or not. Then the cult is reborn in The Wooden Spaceships, but with a distant planet of the same solar system. What happens then? You got the idea.
 * This happens in Clive Barker's play The History of the Devil.
 * In The Light Of Other Days, the technology is invented to open windows to any point in space and time and watch events as they happened. Amongst other things, Moses never existed, being a composite of various historical figures, and Jesus did exist but never performed any miracles. Although the was explained as being the result of.
 * In the Space Odyssey series by Arthur C. Clarke, the idea of God apparently comes from the Monolith, specifically the version that uplifted hominids into humanity. In 3001, humanity has finally discovered this Monolith (dubbed TMA-0), and traditional religion comes to an end. Curiously, though, many people are still either Deists (believing in not less than one god) or Theists (believing in not more than one).
 * Philip K. Dick loved to explore this topic, too. Religion is either mocked, played with or downright condemned in many of his novels.
 * The Doctor Who book Night of the Humans plays out this trope in a truly bizarre fashion. The Doctor responds to a crash-landed alien race on a massive pile of space-junk that is threatening a nearby planet. This interesting premise is quickly overshadowed by an incredibly unsubtle Strawman Political message that turns the entire book into one long and extremely dubious Aesop about how all religion is completely eeeeeevil. The chosen 'god' of the crashed humans turns out to be a creepy, creepy, clown called Gobo used as a (very) heavy-handed metaphor for all religion.

Live Action TV

 * Star Trek: Voyager:
 * An episode concerned a planet that was filled with corpses. The crew found one person who was not quite dead and revived him. It turned out that on his planet, people who are about to die are sent through a portal to the afterlife, and he was understandably distraught to find that it was actually sending them to another planet where they stayed dead. However, the episode had an ambiguous ending, where it's hinted that their afterlife does exist in the planet's rings, and the planet filled with corpses is probably just some kind of temporary holding space.
 * Voyager also had an episode about Neelix questioning his faith after dying and being resuscitated, which showed him that there is nothing after death, instead of the Talaxian afterlife he expected.
 * Many times in Star Trek: The Original Series:
 * In "Return of the Archons," the people of Beta III are all zombies under the control of the omnipotent Landru.
 * In "For The World is Hollow and I have Touched The Sky," the people of the spaceship Yonada have forgotten they're in a spaceship and are ruled by an unforgiving Oracle that can deal out instant, painful death should anyone disobey.
 * In "The Apple," Kirk once again.
 * The most egregious example in the whole of Trek has to be the Star Trek: The Next Generation episode "Who Watches the Watchers". In it, the Enterprise crew accidentally injure a member of a primitive society and take him back to the ship for treatment. When he recovers consciousness and sees Picard, he decides the captain is God and manages to convince the rest of his people to worship him. Cue Picard and co sitting in the observation lounge going "Religion is bad. Don't follow a religion. 'Cos religion is bad." Gene Roddenberry expected the episode to be controversial but it had so little relevance to real world religion that no-one cared.
 * Red Dwarf:
 * A news report reveals that archaeologists have discovered the long lost first page of The Bible - "For my darling Candy. The characters and events depicted in this novel are fictitious. Any resemblance to actual persons, living or dead, is purely coincidental." Apparently the page "has been universally condemned by church leaders."
 * Averted with the Cat people. Despite Cloister being Lister, Cat does not believe for one second that Lister is him.
 * Of course, Cat is so self-centered that if he even considers the idea of God worth bothering with, he's convinced that he is God. Not to mention that Lister both dislikes the idea that he was deified, is perfectly aware of the fact he is not even remotely divine, and has personal habits that would make just about any faithful religious person disown the very thought he could actually be their god.
 * Subverted in Stargate SG-1. Our heroes constantly prove to societies that they are serving false gods and that their religious artifacts are actually advanced technology, but various members of the SGC retain a belief in God that no one ever tries to dispute.
 * In fact, Daniel Jackson half accepts that The Ori are God-esque, but he measures them as unworthy. Believing that any 'God' that would request genocide SHOULD NOT be worshipped. This actually seems to reflect the way he judged himself and The Others when he was ascended. As far as he is concerned The Ori are, higher plane or not, evil. Therefore the moral concept put forth seems to be, whether they are real or not doesn't matter, don't let 'Gods' force you away from healthy human morals.

Video Games

 * The central aspect of the Assassin's Creed metaplot concerns advanced technology that was used to perform the miracles in various religions. The ending of the sequel reveals that . If you're willing believe Ancient Conspiracy, of course - which is exactly what they want you to think.
 * Deus Ex Invisible War makes this one of its major themes in a glaring change from its predecessor, Deus Ex. In Deus Ex, religion and spirituality were themes that ran parallel to the setting and plot, but never outright stated to be either "right" or "wrong." In Invisible War, however, all religion is subsumed into The Order, and The Order is . The player is given the chance to break the news to an Order member, with predictable results.

This change can be seen easiest with The Knights Templar in both games. In Deus Ex, they were the surviving descendants of the original Knights, who had remained as religious bankers. In Invisible War, they're one of the only truly "black" factions who will plunge the world into an extremist, theocratic dark age if they win.
 * As an example on how religion is treated in the first game, Morpheus (an A.I.  developed by a surviving Knights Templar) claims that God is not only man-made but made out of a desire to be observed. Morpheus believes humans feel pleasure when they're watched, so he concludes religion was invented to give this pleasure. JC Denton, however, disagrees and argues with Morpheus on the matter ("Electronic surveillance hardly inspires reverence. Perhaps fear and obedience, but not reverence").

While Morpheus is never proven "right" or "wrong" about religion, he does foreshadow plot details with the conversation. Later on, JC Denton is given the option to reject  desire to play God.
 * Dragon Age: Origins is either an aversion or a subversion. Chantry says that the Maker is just lazy, prayers are not answered, religion is not magic (note that Religion Is Magic in all other BioWare games which have magic), templars are dumb, killers and drug-users, and clergy even refuses to bless an army at some point, making you think that trope is played completery straight... and then the game starts quoting The Lord of the Rings without Deconstruction. In case you didn't know, The Lord of the Rings is about Iluvatar's guidance. The religious outlook of the game is probably something like "God Is Good" but religious organisations can do some pretty stupid things.
 * Religion in Dragon Age is a lot more complicated than that. Supposedly, prayers aren't answered because of mankind's hubris. The priest refused to bless the knights because what they were asking for wasn't a simple blessing, but a guarantee of divine protection, something she couldn't provide. The Templars are a lot more morally grey than their name implies, and overall, the game leaves the existence or nonexistence of The Maker ambiguous. Word Of God is that they intend for it to stay that way.
 * Invoked in Fallout 3:
 * The cult formed around Harold, a ghoul who has turned into a large tree. The cult in the Oasis worship him as a god and blithely ignore and over-interpret his protests otherwise. If the player character finishes the relevant quest by killing Harold (which is what he wants) the cult more-or-less thank you for freeing them from their religion, and are suddenly able to see that Harold wasn't a god after all.
 * This trope is also in play with the church of Atom in the town of Megaton, who worship an atomic bomb as a potential creator billions of universes. Confessor Cromwell, who is effectively a preacher for the religion, stands all day in a pool of irradiated water and it's implied that this has driven him mad, or at least less sane.
 * Which is based on an idea that scientists have thought about in that in every atom is a universe. So there is some credit to it.
 * They also made sure that a less moral (or simply more nosy) character can find out he's a hypocrite. Despite his insistence that Children of the Atom be sober pacifists, in his desk are a bottle of whiskey and a gun.
 * Averted with the other Fallout games, namely the Followers of the Apocalypse and the Mormons now called New Cannan.
 * In The Last Resurrection Jesus is the final boss, and is portrayed as a genocidal lunatic personally responsible for Nazism.
 * In Halo, activating the Halo Array will not ascend the Covenant to godhood but wipe out all life in the Galaxy.

Western Animation

 * There is one episode of the Simpsons where Homer proves that God does not exist mathematically. Flanders destroys all the evidence.
 * Futurama parodies this trope when Leela finally finds out the truth about the origins of the universe and the meaning of life (which we the audience do not get to hear), the only thing she says is, "so every religion is wrong!" Contrast the example on Religion Is Right where Bender meets God. Or what could be part of God after being hit by a satellite.