As the right of each sentient species to live in accordance with its normal cultural evolution is considered sacred, no Star Fleet personnel may interfere with the healthy development of alien life and culture. Such interference includes the introduction of superior knowledge, strength, or technology to a world whose society is incapable of handling such advantages wisely.First Contact, where a technologically advanced society meets a technologically primitive and culturally different one. Case in point: much of the European age of exploration and colonization, which included a great deal of war, exploitation and cultural assimilation (both forced and not) across Asia, Africa and the Americas, including cultures that, according to modern research, may have been more advanced than we once believed. It's mainly for this reason that Science Fiction writers came up with the concept of the Alien Non-Interference Clause: in the future, it is believed, people will have learned from the mistakes of the past and take steps from preventing the same mistakes from recurring as humans explore space. Of course, like the original Prime Directive, such rules are ultimately a Plot Device that bring conflict to a story. Crash landing on an inhabited world when this rule is in force brings obvious difficulties. Trying to study an alien culture without being discovered is a popular scenario. And where do you draw the line? Is there a point where a species is officially "mature" enough to let them in on the secrets of the universe? Does non-interference mean you're morally obliged to let a species suffer or die because it is their "natural development"? A common twist on the trope is to have such a law in effect, and then come across an alien race that is eager to gain tech and knowledge from the humans. What happens then? Can you get away with telling the aliens You Are Not Ready? Where does the rule stop being about "preserving alien cultures" and start being about "keeping the humans (or The Federation) as the dominant power"? And if the aliens want it bad enough, are we really going to be able to stop them from figuring it out?
- From Marvel Comics: The Watchers have an "observe, don't interfere" law in place (thus their species' name. Eventually revealed to be the result of accidentally destroying another species by giving its members advanced scientific knowledge way too soon.
- In the Buck Godot comics, humans are forbidden from interfering with any race not advanced enough for space travel by Lord Thezmothete.
- In He-Man and the Masters of the Universe, Zodac and other Cosmic Enforcers are tasked with observing all that transpires in the Universe but not interfering except to maintain the balance between good and evil. Because of this on the rare examples when they do interfere they are just as likely to help the bad guys as the heroes.
- Star Maker, a 1937 novel by Olaf Stephenson (who inspired many of the "golden age" sci-fi writers) has the Symbiont race, Sufficiently Advanced Aliens who keep their existance hidden from "pre-utopian", pre-spacefaring races, revealing themselves only after a race achieves both of those so the fledgling races don't lose their "independence of mind". (Pretty similar to the Vulcans that came after.)
- Orson Scott Card's later (chronologically) book in the Ender's Game series, Speaker of the Dead and Xenocide mostly, have had this rule put in place by the Starways Congress years after the obliteration (almost) of the Buggers in the first book, and grown-up Ender's writing The Hive Queen about what they were really like. But after Ender gets involved in affairs between the humans and the pequeninos ("piggies") on his new home of Lusitania, it's discovered that the piggies want spaceships, and to become space explorers themselves, in spite of not having passed a lot of technological milestones such as electricity. This causes considerable commotion among the xenoloigists [[spoiler: leading to the eventual decission to screw the rules.
- Animorphs has "The Law of Seerow's Kindness", a law passed by the Adinites forbidding sharing technology with other cultures after one such incident upset the balance of power in the universe.
- Elizabeth Moon's Remnant Population has "The People", Starfish Aliens who until events in the book, unwittingly share their planet with human colonists. After some humans try to land new colony ships on their nests (and get killed for it), they seek out and find Ofelia, the willing last human of a failed colony hundreds of miles away, who kept the colony's tech running for her own use. Unaware of the non-interference rule (which exists even though humans have never met another intelligent species, as they made many assumptions about what aliens will be like), Ofelia has to show and explain things like electricity to The People, initially so their curiosity doesn't kill them with a high voltage current. But it turns out The People are extremely intelligent and hungry for knowledge, to the surprise of all and the chagrin of the human officials and scientists who get sent to "undo the damage" (some with good but misinformed intentions and some crossing the line into "keeping the humans in charge").
- Star Trek is the Trope Codifier: whether or not they did it first, they're the one most people have likely heard about. The series has been somewhat inconsistent over where the borders of the rule lie, but as noted on the Prime Directive page, there is usually a hole somewhere "big enough to fly the Enterprise through".
- One Next Generation episode, First Contact (no relation to the movie) deals with the justified aspects of the Prime Directive. The Enterprise crew are on a secret first contact envoy to the Malcorians, a species on the verge of warp capability. Over wine with the planetary Chancelor, Picard discusses with him the justifications of the Prime Directive and their obligation to leave the Malcorians alone if that is their wish. The Malcorians, who mirror 20th century humans in many ways, are undergoing cultural turmoil because of their rapid march of technology. Meanwhile, Riker was doing covert surveillance when he was injured and hospitalized: it becomes difficult to hide the fact that he's not one of them and he almost dies because the distrustful minister of security tries to use him to convince the Chancellor not to trust the humans. Because of this, Chancelor Durken ultimately decides that his people are not ready to learn they're not alone, though he promises to spend money and effort on education so they'll be prepared when the time comes.
- Babylon 5 may or may not have had a formal rule but advanced races could and did deny technology to other races believed to be "not ready".
- In the episode, "Deathwalker", a renegade Dilgar scientist named Jha'dur is captured but bargains her freedom with a breakthrough medication that grants immortality. Before her medication can be mass-produced, she is killed by the Vorlons. Ambassador Kosh tells an assembled audience 'You are not ready for immortality'.
- Epsilon III was declared off limits to all (episode "A Voice In The Wilderness") because the technology of the giant computer contained there would give any one race that got it an unfair advantage.
- After the Vorlons had left the galaxy, a number of people attempted to travel to Vorlon to lay claim to the advanced technology there; all of them got shot down. Lyta explains that humanity was not presently meant to have Vorlon technology and won't be for about a million years.
- On the other hand, in the Crusade spin-off series, Captain Matthew Gideon would launch a full spread of modified probes (uploaded with considerable information about Earth and the Interstellar alliance at a pre-hyperspace planet where the local government was supressing knowledge of the humans. He was questioned about whether this violated any non-interference principles and replied "Screw 'em.".
- The races of the Stargate universe vary in their approach to this. The Tau'ri (Earth humans) reject it and hold it as their duty to help humans and less advanced, non-hostile races on other worlds but may withold tech that is "too dangerous". The Tollan follow it strictly after their neighboring planet self-destructed because of technology they were given. The Asgard will share with lesser races (humans most notably) but not weapons tech, the Ori flaunt their tech and meddle all the time, and the Goa'uld play the role of the European conquistadors by posing as gods to less advanced civilizations.
- In Doctor Who, the Time Lords adopted an official policy of neutrality and non-interference, acting only as observers save in cases of great injustice, after granting advanced technology to the Minyans who then destroyed themselves in a series of nuclear wars. Which is not to say they always adhered to it...
- The Pangalactic Federation of ''Star Ocean" has the Undeveloped Planet Preservation Pact, which differs from the Star Trek version in that people don't get in as much trouble if they break out the advanced tech to save their own lives.
- While none of the civilizations of the Mass Effect verse have such a rule, salarian scientist Mordin Solus holds the view that there should be one, citing the fiasco with the Krogan as an example of why.
- [[hottip:Background: As a primitive species, the Krogan had been given advanced technology to help turn around a losing war. But the Krogans' prodigious birth rate (previously balanced out by the fact that their homeworld was a Death World where only one in a thousand Krogan survived to reach adulthood), combined with their natural aggression, led to them turning around and becoming as much of a menace to other sapient species as the aforementioned bugs. It took the genophage to keep them from overrunning the galaxy.]]
- Parodied by Futurama with Directive B10.8:1 A.K.A. "Brannigan's Law"; the law itself is pretty straight but Brannigan doesn't actually understand it himself, and ends up breaking it at one point.
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