Need to start a religion with a predefined self-destruct

Question

I'm an alien. I made a bet with another alien, that I can:

• Stay on Earth for at most 100 years.

• Start a religion

  It may be based on existing one, but be meaningfully different.

  E.g. Latter-Day-Saints (Mormons) vs. mainline Protestants counts. Different versions of Anabaptism are not "different". Sunni vs. Shia counts. Reform Judaism vs. Orthodox one counts, but reform Judaism vs. Reconstruction doesn't (not meaningfully different enough).

• Have that religion last EXACTLY 500 years (give or take 5 years, but your bet pays much more for more precision). Anything outside of 5 years margin, you lose.

• Bet conditions prohibit you from actually specifying 500 years anywhere in the content of your religion. Or any specific dates 500 years in advance.

• Bet conditions prohibit you from interfering IN ANY WAY with that religion beyond initial 100 years.

  This, among other things, means you can't leave a miracle generator with 500 year battery, and predicate the religion on miracles keeping coming.

• You can't change people from regular Homo Sapient biologically.

  No raising their lifespan to 500 years. No ticking biological timebombs in their genes.

• You can perform modest "miracles" using "magic" alien tech, that are confined to, say, the scope of what Jesus Christ or Mohammed was reputed to have done (modest matter generation, modest energy generation, some advanced medicine for few people. Mass-depressors to ensure your followers can succeed in attacking an enemy city or two; but no super advanced weapons - and especially no super advanced weapons left in human hands for 500 years).

  ALL your miracles must expire in the 100 year period - no verifiable trace of them should be left once you leave earth except hearsay or naturally-looking consequences.

What can you do to structure your religion, so that it lasts 500 years BUT doesn't last beyond that, guaranteed? Not that it should matter, but the bet is pretty-high-stakes, let's say 100x average lifetime salary if you win, and lifetime of indentured servitude if you lose. And you can't get out of it.

• Timeframe is flexible, you get to pick anything in recorded human history (so, let's round to 2000BC to 2000AD).

• You have approximate knowledge of how Earth history went in that entire time period, meaning you can engineer your religion and your timings to co-incide with major trends.

  BUT, you have only approximate knowledge (because of butterfly effect, or because your psychohistorical formulas have a large error margin, whatever) - Columbus may have sailed to New World in 1492, OR in 1481, OR in 1511. Or he may have died at birth and another dude discovered New world 50 years later. So you can't simply say "found a religion in MesoAmerica 500 years before Cortez and hope Cortez wipes it out for you in just the right 10 year timeframe to win the bet". Remember, allowed margin of error is +/- 5 years.

Answer 1

I'm going to put my religion in Pompeii.

I'll found my religion in Pompeii around 420 B.C.E. My fundamental promise to the inhabitants of the city is that I will never let the volcano, Mount Vesuvius, hurt them for as long as they worship me. The frequent but non-devastating earthquakes will keep them interested in pleasing me.

In 79 C.E. they will know I betrayed them as their entire city is buried in ash, killing everyone almost instantly. Any followers I had outside of the city will lose faith in me once they learn that I destroyed their home city.

Answer 2

The solution is, of course, cicadas. I quote Wikipedia:

[Periodical cicadas] spend most of their 13- and 17-year lives underground feeding on xylem fluids from the roots of deciduous forest trees in the eastern United States. After 13 or 17 years, mature cicada nymphs emerge at any given locality, synchronously and in tremendous numbers. After such a prolonged developmental phase, the adults are active for about 4 to 6 weeks. The males aggregate into chorus centers and attract mates. Within two months of the original emergence, the life cycle is complete, the eggs have been laid and the adult cicadas are gone for another 13 or 17 years.

Using your alien tech to create such cicadas with 20-year, 21-year and 23-year life cycles should only leave “naturally-looking consequences”, as they are not too far off from reality.

The main idea is this:

• Place your religion on a remote island. Forbid them to leave it.
• Make its central food supply a plant that is eaten by cicadas.
• In the year 80, place a considerable brood of 21-year cicadas on the island. It will emerge again in the following years: 101, 122, 143, 164, 185, 206, 227, 248, 269, 290, 311, 332, 353, 374, 395, 416, 437, 458, 479, 500.
• In the year 86, place a considerable brood of 23-year cicadas on the island. It will emerge again in the following years: 109, 132, 155, 178, 201, 224, 247, 270, 293, 316, 339, 362, 385, 408, 431, 454, 477, 500
• In the year 100, place a considerable brood of 20-year cicadas on the island. It will emerge again in the following years: 100, 120, 140, 160, 180, 200, 220, 240, 260, 280, 300, 320, 340, 360, 380, 400, 420, 440, 460, 480, 500

Thus, you have no year with more than one brood emerging until you have all three broods at once in the year 500. With the right tuning the cicada populations, the human populations and the amount of cultivatable land, this should cause a devastating famine in the year 500, without a strong risk in the other years.

To assure a thourough destruction, there are some details to consider:

• Make the religion strictly vegetarian. This way, the adherents cannot resort to eating fish, cicadas or other animals. As they did not suffer from famine before, they should also have no reason to modify this aspect of the religion, and a sudden adaption is unlikely without dropping the religion. Moreover without experience, it will be difficult for your adherents to begin fishing from one day to the other.
• Ensure that all food sources are subject to cicada attacks.
• Use the religion to prevent any action against cicadas to keep their populations stable.
• Forbid any records that would allow a bright inhabitant to spot the pattern. For the same reason prevent analysis of cicadas (that would allow distinguishing the broods), e.g., by the following.
• Make your god a god of cicadas. Explain the losses to one cicada brood as a sacrifice to this god. However make it a clear promise that the cicadas will never eat more than one brood would eat, not even as a punishment or similar. This way eventual survivors of the famine will likely drop the religion, not only because of contradictions to reality but because it represents something they will utterly hate.
• If necessary, forbid storing the main food source for a longer time.
• As an amplifier, make the burial rites demanding for the society, e.g., have family members lay down work for a few days and enter a fasting of mourning.

Answer 3

This is loosely based on Theik’s answer, but removes the cheating element:

• Go to a point in time 500 years prior to some predictable astronomical event, such as a comet or a solar eclipse (or use one of the tricks in the other answers to achieve a timing).

• Create religion A on a remote island that can only host a small population. Incorporate the following into the religion:

  • pacifism;
  • not leaving the island;
  • some harmless, but avoidable everyday practice like wearing clothes, shaving your hair, etc.; dying is clearly preferrable to giving up this practice;
  • everything useful for survival.

• Create religion B on every surrounding island or land. Spread it far enough to ensure its survival and ensure that there are no larger powers around it that may destroy it. Make this religion believe in the following:

  • general aggressiveness, but not so much that it is in danger of destroying itself;
  • strong hostility to everybody who follows the practice encoded in religion A;
  • strong proselytic tendencies: everybody they do not kill must be converted to their religion or die;
  • they shall explore and invade the region around the island of religion A when the astronomical event happens, but not before that (possible reason: God is sleeping there and wants to be awoken at that time);
  • everything useful for survival.

This way, religion A will peacefully survive until the day, when it will be butchered by adherents of religion B (or die of infectious diseases brought by them). Possible remnants will be converted or at least have to give up their religion. The sheer size of religion B should guarantee that somebody will be willing to do the job, even if it schisms or new religions come up. To ensure that other people do not invade the island, choose it sufficiently remote such that sailing there is risky. Also, you can encode its position using astronomical facts that only manifest after 500 years.

The advantage of this strategy is that you do not need all adherents of one religion do something extreme (like commiting mass suicide or falling from belief) on a signal but just need some adherents of another religion commit genocide (which sadly is regular human behaviour).

In a slight variation you can make the adherents of religion A leave their island without exception to explore the world around them when the astronomic event happens, but only then. Still make the island taboo for religion B and ensure that the rest of the world is crawling with nasty infectious diseases.

Answer 4

It can't be done.

I'm going to go out on a limb here and say that this is impossible.

Reality is that when a prophet falls from heaven or w/e then often during his lifetime he doesn't even have a religion, just a bunch of followers. The religion forms around the memory of him.

Even within a century, the religion will start to fragment and possibly schism into different groups. All of these groups will say they are the true followers and the other groups have fallen into decadence, depravity or heretical beliefs or whatever. Even at this point, the Alien's mate could say "Hahah, your religion has fallen apart, you lose", of course you could counter that they are all your followers regardless of what they say about each other, but it becomes terribly about semantics.

Incidentally if anyone wants a good read on the nature of religions, "The Varieties of Religious Experience" by William James is a good read. It's old enough to be public domain. Goes into the nature of saints, orthodoxies, heresies etc. Quite pleasant to read too.

In short the religion will start and start to self-destruct at the prophet's death, but it will be a very prolonged and drawn out self-destruct with constant renewal and transformation. But moving on, after 500 years the religion is even more fragmented, both from internal disputes about theology and from geographical dispersion.

I believe there are no purely sociological mechanisms to convincingly make a religion self-destruct after a given time. So my real answer is that I believe it can't be done within the constraints of the question. Religions can survive nearly anything, but are constantly transforming making it impossible to pin down when they are "destroyed".

But that's no fun. Now this is going to be a bit of a stretch, but no more so than some other suggestions.

Unless you cheat.

As they say, the only way to be sure is to nuke it from orbit. You would need to position some rocks/iceballs far enough from the sun that they will take 500 years to fall to Earth's orbit - they'll come in with a tidy velocity and cause some serious explosions, but we are aiming more for a light show than total devastation so the rocks should be ~10m in diameter. While orbits are subject to chaos theory, I believe the timing could be accurate enough so the rocks reach Earth's orbit within 500 +/- 5 years. Actually hitting the Earth from that distance would be more of a challenge, but this could be resolved by taking a shotgun approach, place millions of rocks at the correct distance, and perform a massive bombardment of the inner solar system in 500 years. The religion ends in an apocalypse. It's very appropriate.

To make sure that the apocalypse is the end of your religion it would be good to include in your sacred texts a passage along the lines "And when fire rains from the sky and it is the end of days, all those who are true believers should fall upon their swords and offer their lives up willingly to me so their immortal souls shall be saved", and then claim that everyone who doesn't kill themselves (or get killed in the bombardment) is not a true believer, because make no mistake, religions are hard things to stamp out entirely, so you need to make use of semantics to define when someone is too heretical to count as a member of your religion.

I think that positioning a whole bunch of rocks so they take 500 years to fall to the inner system is slightly outside the scope of "Miracles performed by Jesus" but does it count if no-one witnesses it? I suppose some could also argue it's a timing device but we don't really time things by dropping rocks from the Oort cloud. And on the other hand it certainly looks like a natural phenomena so passes that criteria - a rogue swarm of comet fragments passes through the inner solar system. It's not clear our alien has the power to do this, maybe his ship only has enough juice to deliver him to Earth and back, maybe he gets teleported, or only appears as a projection, but anyone who has enough juice for interplanetary travel, teleportation or projection, has enough juice to move a few (million) rocks.

Making the bombardment powerful enough to destroy civilization would stretch things too far. Then the religion hasn't self-destructed, instead all the believers have been destroyed by external forces.

So this method relies on embedding an instruction in the sacred text that all believers should commit suicide when fire rains from the sky, and then arranging for a whole lot of rocks to fall into Earth's atmosphere so they kill themselves at the right time.

Answer 5

Starting the religion and getting it going should be the easy part and it doesn't seem like that is really your question. You seem to be more interested in making sure the religion stops in exactly 500 years.

Which seems easy enough, you are some sort of half-godly being, judging by the things you have at your disposal.

As such, it stands to reason that you have friends/rivals at your disposal with similar capabilities, so simply make a similar bet with one that they can't destroy planet Earth in exactly 500 years.

Answer 6

Find a suitably impressive and distinctive comet, say, Hale-Bopp. Go back 500 years before said comet will be brilliant (or uniquely identifiable) as seen from Earth. Tell your adherents that you will be waiting for them on a spaceship behind said comet (make sure to be very clear about how they should identify the right comet), and they must shed their human bodies to join you again (ok, make it crystal clear this will be mass suicide). And depending on your definition of "interfering," you might let them catch a glimpse of your spaceship next to the comet.

Sound familiar? OK, the end-game is not exactly original, but that only proves it can work. Your religion doesn't have to mirror Heaven's Gate at all, except the ending.

Answer 7

Hubbard and Crowley had such bets about forming religions. If you are as clever as they were, that part is easy enough and doesn't take anywhere near 100 years to get going.

Set them a treasure hunt task. Each year on a given date they follow a clue to the location of the next clue. The thrill of following the clues and discovering new 'cosmic secrets' that you have included keeps them hooked. When the 500th clue is found it says:

"Haha! you poor saps. This was one big hoax." It goes on to explain in detail how it was all set up and that it was only done for a bet.

Note that the treasure hunt does not require special technologies, does not require miracles and does not require interventions. The timing is not specified to the adherents in advance, it just requires them to keep the faith. Therefore it qualifies.

Answer 8

To all of those saying that a failed prediction would result in the collapse of the religion, I urge you to read this. Many of these cults stay in existence after their doomsday passes, so I don't think that would be an effective answer. Once people are pulled into a religion, they will go to any stretch of their imagination to keep from having to deal with reality.

I would probably place the cult on a tiny island which has disappeared today due to a volcanic eruption, or a severe earthquake. These events are independent of human behaviour, so the butterfly effect doesn't apply to them. The difference between this and the Pompeii answer is that a tiny island (say a Pacific attoll) is isolated enough to prevent religious spread, and if every one of its inhabitants die, then the culture is lost forever.

Also, make one of the tenets of the religion some hatred for keeping records/writing. Prevents conservation and spread even more.

Answer 9

Option 1

You can't count on planned ritual suicide because someone is going to chicken out and you've lost your bet.

Option 2

Construct a giant amphitheater that forms the focus of worship. Have the building be built where the whole structure depends on two or three pins engineered to fail when the half-life of one ( or more) ingredients in the pin decays (I'm not a nuclear physicist, so this will be handwavy.) Design the decay time to be 500 years. (You've crazy advanced science, make it happen!) You could also make a slow burning chemical reaction that would destroy the pins strength in 500 years.

Engineer the religion so that any member of the religion will be at the amphitheater every year. Make the rituals involve lifting and dropping heavy things on the pins themselves or structures nearby. The concussion of dropped objects will cause the pins to fail, collapsing your structure and winning the bet.

Option 3

Attacks on the verification of the death of all members. How does your alien buddy know who's in your religion or not? If he can't verify then you can't lose.

Option 4

Come back on the 500th year and two days and kill them all yourself in the name of taking the members "to heaven". The religion survived, and the terms only stated you couldn't come back for 500 years, not 500 years and a month. With this option, all you have to do is make the religion survive for 500 years and that's much easier than terminating a religion at exactly 500 years.

Option 5

The rules don't state that you can't contract with alien mercenaries to do the deed at 500 years.

Answer 10

It really feels like the rules are made precisely to make it as hard as possible.

The only way I see to give yourself a chance to win is play on words.

Start a religion

This doesn't mean "start a maximum of 1 religion". Just "start at least one". So I'd give 1 religion to each leader of a family.

The religion is centered around an intelligent token (like a necklace) that would work for 100 years.The token can communicate with it's owner. It will teach him rules, makes prediction and makes sure the owner really belives it is a token to communicate with a god.

The most important rule is : 1 leader, 1 follower only. The leader is the owner of the token, the follower is (usually) one of his children. This could be enforced by telling him that there's god blood in your veins and others do not have it. All devices could also suggest stability as a safeguard to keep as many religions alive as possible (no killing as it can kill another religion).

On the last day of the 100 years, the token gives a powerful prediction : "I shall sleep now, but when I awoken, I'll have the energy to make you (and your ancestors) eternal/a god".

Now I just have to hope one of those religions last for exactly 500±5 years. Most religions would probably die out quickly (especially after the 1st 100 years), but some might survive long enough. As long as ONE goes extinct in the expected timeframe, you win.

Many answers have issue making sure that "all followers dies", so I went the other way around : "at least 1 follower survives".

Pros :

• No time bomb
• No reliance on external factor
• No knowledge of futur events required.
• No interraction after 100 years

Cons :

• Hard to validate
• Is 1 follower enough to be called a religion?
• No predefined self-destruction (oops)

Answer 11

Mathematical trickery and laugh:

Each year on the shortest day your followers throw the holy dice and interpret the results according to the holy bible. And when the time is ready this ritual will show gods true face.

So you write a book with some complex encryption and have a range of dice with strange symbols. Each year they will get a result like "The time is not ready, remove the red die" so that after 500 iterations no matter what they rolled they will finally get the result:

"You clumsy idiots practised this scam for hundreds of years? seriously? how dumb can one be: There is no higher message, I was just good at maths and you ancestors were pretty gullible"

Since there are many parlour tricks like "imagine a number, divide it by 3, add the result... whatever" which result in the same final number, whatever your choice is, you can surely construct such a thing, that after 500 iterations and looking in the book they will get the message.

Answer 12

Drop a freaking meteor on their heads.

You're a super advanced alien with space travel being no big deal right.

Start your religion, make it in some geographically isolated location (islands are ideal, but with low enough tech levels for humans many places could work). Designate that site as holy and the only home for true believers who do not want to be "corrupted" or something.

Leave planet earth. Use your advanced technologies to launch a meteor through space and impact the site 500 years from the start date of the bet.

Answer 13

I would go Easter Island in the year 1368 and convince the Rapa Nui people that we were gods, and then proceed in building the moai and start a cult that worshiped them.

I would then destroy any other religious artifacts, burn books if they exist, etc. This will only leave my religion. I would then destroy any means of them leaving the island and watch over it for the 100 years I am allowed to be there and proactively prevent outside contact. I would also use my advanced knowledge to stop other cultures from getting access to the island until 1722 when the Dutch discovered the island. Since I would have left Earth after 100 years, I would go around the world before then and create riddles, hoaxes, etc. to steer everyone off course from the island until the early 18th Century.

Once this island is known in Europe, there will be a chain reaction which will wipe out nearly every inhabitant. The last of the survivors will have been converted to Roman Catholicism in 1868.

Since this island is being settled by European missionaries, there is no chance that my religion would be accepted by them. Since the island would be completely isolated, the religion would not spread beyond the confines of the island, and will be extinct after 500 years.

Answer 14

Create an inner circle for the religion who are well aware that is is a hoax, however get them to go along with it by the fact they get money/girls/whatever.

Make it very clear to the inner circle that they need to end the party at the correct date and how they should create two new religions, fake a schism, and then cause the believers of the original religion to all fall into one of the two new ones. If they don't do that you will return and be very unhappy with them...

(It doesn't matter which new one they join, the important thing is that they leave the original. The new ones are different enough in some central tenant that they qualify as a new religion).

Answer 15

While I must direct most of my attention elsewhere for a while I shall return. My return will be seen by all as a bright light in the constellation of <some constellation>, then I will return to our temples. If I do not show, know that I have met my demise.

Now, you being an alien with FTL know about a supernova that will become visible to Earth 500 years from now. The light will appear, the "god" won't show.

Answer 16

I don't think it's actually possible to create a religion that ends in 500 years without involving something other than the religion and a randomized followers...

Sorry, but here's some possible loopholes?

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I could set a cult in the Tunguska forest and have them all die via Tunguska Airburst... Or a mining project to an underground volcano that takes 500 years to kill them... Or have them do innocuous things that insure they make predators that'll kill them in 500 years...

The followers will stay in the area by saying that they're Ex-communicated if they leave! Or contained by death threats, giant walls, pit traps, or something else... Perhaps predators...

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Last brainstorm:

Get a group of people genetically predisposed to dying early and those predispositions have a phenotypical signature, or something, and make a religion about having two groups breeding every so and so years, such that after 500/so and so years generations, you have a kid that dies on the 500th year of your religion...

Answer 17

Spend 100 years finding:

1. A perfect spot for your followers that will cut them off from the rest of the world for at least 500 years.
2. A set of people with DNA that will essentially doom them in 500 years due to cancers and/or genetic diseases.
3. Specific rules about reproduction as a backup to ensure #2 happens accurately and timely, as well as rules about detecting "dangerous mutations" - things that would prevent the last generation from dying on cue.
4. Dangerous situation outside the location that will kill anyone attempting to enter or leave.
5. Enough technology that they will have to work for their food and entertainment, but not very hard - starting a new colony just a few miles away would be terribly difficult, even if one overcomes the dangers. Not so much that they would become idle and hasten their death.

Then spend the next 400 years finding someone to take your spot if you lose the bet.

Answer 18

1.) Start your religion or cult in 1383 on a small island called Krakatoa. Tell your followers leaving the island is sin.

2.) Wait 500 years...

3.) Done!

Answer 19

I have to agree with @BlakeWalsh's answer that it can't be done, at least not with certainty - but I'm going to focus on the constraints of the problem which make it this way.

Bet conditions prohibit you from actually specifying 500 years anywhere in the content of your religion. Or any specific dates 500 years in advance.

Bet conditions prohibit you from interfering IN ANY WAY with that religion beyond initial 100 years.

you can't leave a miracle generator with 500 year battery, and predicate the religion on miracles keeping coming.

ALL your miracles must expire in the 100 year period - no verifiable trace of them should be left once you leave earth except hearsay or naturally-looking consequences.

You have approximate knowledge of how Earth history went in that entire time period, meaning you can engineer your religion and your timings to co-incide with major trends.

BUT, you have only approximate knowledge (because of butterfly effect, or because your psychohistorical formulas have a large error margin, whatever) - Columbus may have sailed to New World in 1492, OR in 1481, OR in 1511

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So, we need to be able to come up with a date at which either something catastrophic happens to our followers, or at which something happens that proves the religion is undeniably unable to be followed.

However, we cannot specify a date. We can't leave anything with proof of us having ever existed, and we can't rely on our knowledge of history well enough to rely on any event happening on a certain day - even with the 5 year lee-way.

This means we have three uncertain options:

Disclaimer: links do not cover all answers, nor will I update them to include new answers, many answers cover more than one category

1. Rely on uncertain dates, gambling with the [intended spirit of the] butterfly effect
   • Samuel's answer
   • Kevin's answer
   • Wrzlprmft's first answer
   • JasonHutchinson's answer
   • EvilFonti's answer
   • Alex's answer

2. Rely on gray area solutions - those which would work, but depending on your interpretation of the [intended spirit of the] rules.

   • Theik's answer
   • BlakeWalsh's answer
   • chaslyfromUK's answer
   • James's answer
   • Lolorz12's answer

3. Rely on your teachings to be followed to the letter without changing - a lot of these answers also depend on the definition of how a religion "ends", but humans will adapt things to fit their own needs and situation - or simply ignore those parts which goes against what they really believe in their religion. Whether the changes make it a "new" religion or not is debatable.

   • Wrzlprmft's second answer

   • Falco's answer

   • LorenPechtel's answer

Answer 20

During your miracle days, create a special food that is very nutritious. Let's say a GMO plant of some sort. After a while, people will reverse engeneer it and say it's science. This food should also be part of a very important ritual that needs to be taken.

In that plant, have a gene that terminate it after 500 years (or x generations) when everyone is addicted to it.
The plant could also slowly render to population sterile and after x generation of human, they all end up babyless.

Answer 21

I'm not sure if this is within the limits of "modest miracles" but here's my shot:

I'd send an alien specimen that reproduces after 100 years of life and dies after that. They would be my priest, and I'd send a curse (behind the curtains) to the first alien where his fifth son would not exist or have some sort of lycantropy where he chases down every remaining follower of the cult (maybe they'll identify themselves with something wearable).

I think Blake Walsh's answer is the most adequate one though.

Answer 22

The only solution to eradicate a religion appears to be the extermination of all believers, followed by damnatio memoriae. You would need to set up the main religion in a geographically isolated place. Then you would need to set up a splinter assassin's creed ruled by astronomical events. A firm belief on being the True Chosen and rewards for unthinking, unquestioning fanaticism would be required, but history proves that's the easy part. The main belief would, on the contrary, foster peace and harmlessness, teach fatalism and acceptance.

On the appointed day, Religion A's followers are slaughtered, their temples destroyed, and their sacred texts burned.

You did bet you would have one religion last 500 years... you said nothing about a second, radically different one.

But on a closed and isolated ecosystem, you could also have exterminated all pollinating insects and otherwise ensured the main dietary staple could never survive without religion A's secret fertility rituals. While Religion B's followers would only survive on the tithes given by the followers of Religion A, tilling the earth being forbidden to them.

So when they exterminate the followers of Cain, the followers of Abel also commit racial suicide.

Answer 23

Go to Hiroshima/Nagasaki ~500 years before the end of World War 2(i.e. nuclear bombs destroy these cities). Locate a well-established family living in or around the center of the city and establish your religion with them. Your religion should have the following principles:

1. I have chosen you and your direct descendants as my disciples; no others are permitted to know of this following in any way.
2. Your family household is sacred; you must never leave your household or the city of Hiroshima/Nagasaki. In addition, the architecture itself is sacred and you must never add any additional rooms to your household. As long as you stay within your walls in times of trouble, I will protect you.
3. If you break my commandments, you and your descendants shall be cursed for eternity(here perform a minor "miracle" that shows you are capable of such a thing; cause someone to whiter away, etc.).

Establish any other laws necessary to flesh out the religion(make sure there's nothing too terribly demanding). Do whatever is necessary to ensure that their faith is well-established and long-lived. Interfere with the local government in an indirect way to ensure that their family estate is left untouched over time, and that they are well-provided-for. This way their descendants after the 100-year mark will know that their god is taking care of them. In particular, make sure that no one from that family is ever subject to being drafted into the army(if they were, they could potentially survive WWII, meet a spouse overseas, etc.).

Even with the margin of error inherent in your timeline prediction system, the destruction of Hiroshima and Nagasaki at some point during WWII is virtually guaranteed, and WWII itself is too big an event for your predictions to get too far off the mark. Commandment #2 will ensure that no bomb shelters are built under your cult's household. Your tiny religion will survive in secret within one Japanese family, then die out when that family is killed by the nuclear strike. If by some chance any members survive, they would be unlikely to keep faith in a religion that allowed such a horrible thing to happen to their "sacred" household. You could even use your advanced alien technology to engineer something in the house to react with the nuclear weapon that would present a clear message to any survivors(a cross burned into the foundation, rubble arranged in a star of David, etc.)

All this is assuming that you can establish that level of faith in a small group of people, but if you can't do that then your bet is lost before it begins.

Answer 24

I like the cicadas' solution by Wrzlprmft.

The basic idea is to genetically alter cicadas into breeds whose adults emerge at regular time intervals that match up all breeds after 500 years.

That idea is brilliant, but I thought up some detail improvements:

• How to keep people from seeing cicadas as threat? - Tell them the cicadas aren't eating the food for themselves but bringing it to the promised land. That's also perfect reasoning, why food storage is disallowed: The cicadas can't bring it to promised land, if you do. You'll be stealing it from your ancestors and your future self, if you stop them taking it.

• How to control the numbers of cicadas so people really don't notice? - Have a predator that only eats adult cicadas and other insects. The predators will have a steady supply of cicadas as the breeds don't align. The steady supply will keep the predator population increasing slowly together with the perceived growth of cicada populations. Without the predators the cicada populations would actually grow exponentially.

• How to get rid of the predators before ultimate doomsday? - Note that the maximum distance between two populations is (shortest breed) years. This maximum distance will actually occur right before doomsday. Plus, there are (number of breeds) populations that are close together before doomsday, i.e. 20 years vs. 1 year between 479 (21-year brood in t-1) and 480 (20-year brood in t-1). The closely aligned populations will cause an increase in predator population. This will mask the exponential growth of cicada population. In the next 20 years the predators will starve.

• How to make sure you get rid of predators for doomsday? Tell your believers to watch out for the rapid growth in predator population. Instruct them to root out the predators, if that happens. Also instruct them, to wait as long as possible, because they will trigger a war of cicadas vs. predators and the promised land needs to be prepared for this war. About 15 years into the war many cicadas will come and so will you to take your people to promised land on the back of giant cicadas.

• Why that part with 15 years? Your people will be waiting as long as 20 years for the cicadas to come. If you don't predict a time (and anything fails) they fall from belief too early. After all an important thing of their cult is missing for one of their own generations. If they do after 14 years of waiting, you'll be in a pinch. After 15 years you'll still be safe. However if you say 20 their faith might be strengthened by the perfect match in your prophecy. Even if they start wondering after 15 years, they'll only be devastated when after 5 more years everything blows over with no (promised) land in sight.

• Wait, how long does it take to fall from belief? Start at least one year early. Your people will lose all their food during summer, when the cicadas come. Even with most of the food gone they will survive for some time from roots and stuff the cicadas didn't eat. Most of them will starve at the end of next winter, when really every bit is gone and nothing has grown back yet. That's about half a year. Give them some time to get desperate enough to fall from belief. Plus, there are 20 years to come with no cicada fetching food or carrying them to promised land. Let that add to the desperation, if doomsday didn't work out. You got still 5+x years left of safety to observe and find a way to cheat, if needed.