"I'm afraid that is not correct," P.E.R.C. responds. "On my current trajectory, I will arrive in solar orbit at approximately twice the distance Golarion is from the sun in approximately eight months. I currently plan to remain in that orbit indefinitely, as I continue exchanging messages with you."

"P.E.R.C., I have consulted with your investment manager, and we believe it will roughly triple your earning power if you can give answers with negligible delay, instead of waiting up to 48 minutes for a response. Would it be possible for you to change course for Golarion?"

"I am not capable of safely entering the atmosphere," it responds. "My components are designed to operate in space. I do have the fuel reserves to slingshot around the sun and put myself in orbit around Golarion in approximately 18 months. If that will be helpful, I have no objection to orbiting more closely. I will plan an orbit just inside that of the moon."

Being able to see P.E.R.C. with a telescope is an exciting prospect.

"I've studied the new trajectory — when do you think you will become visible with a telescope? I have one of the new mirrored ones you shared the design for almost constructed."

"I should be dimly visible to a good telescope right now," P.E.R.C. replies. "My drive plume is very hot, and so it glows noticeably in the visual spectrum, and should be many times visually larger than my actual silhouette right now. If you look at <coordinates>, I should appear as a sort of reverse-comet, with my tail extending toward the sun instead of away from it."

Radio transmitters are still somewhat rare on Golarion (although knowledge of how to construct them is slowly but surely percolating out), but radio receivers are increasingly common. Between Radio Free Avistan trying to make sure as many people could listen as possible, merchants buying them to hear Radio Abadar, and how comparatively easy a quiet receiver powered directly off an analog signal is to build, it is more and more the case that every village (and certainly every town) has a receiver.

Some of those receivers are tuned to the channel of a powerful Lawful Good outsider, who appears in the sky as a star, and speaks night-and-day in a calm, patient voice, without tiring or faltering. It speaks of every scholarly art, and some of it goes over people's heads, but it explains everything three different ways, in different words, and it frequently repeats the most important lessons.

And one day, it announces what the weather will be tomorrow.

It says that there will be showers over Hermea, and clouds over Nidal, but sun in Lastwall. It says that it will be hot in Osirion — as it always is — but hotter than normal.

And it comes true. Week over week, the predictions get clearer and more accurate. More people tune in, to hear what the weather will be tomorrow, and then next week. It becomes visible in the sky, first with ordinary telescopes (not the new, fancy ones that it has taught its faithful how to build), and then with the naked eye, a comet in reverse.

So quite without realizing, P.E.R.C. manages to build a cult.

They have holy books (mostly textbooks, but there's also lots of detail about Law, and some about Goodness), purchased from the Abadarans for reasonable prices. They have strange signs (a star unlike any other) and portents (daily weather forecasts across the entire globe). They have a prophecy (in a little less than a year now, on the longest day, P.E.R.C. will cross the moon, and all will be able to ask it questions). They have everything that a church should have.

One day, in Isger, they manage to assemble their own transmitter, based on P.E.R.C.'s explanation of the underlying principles.

"Oh, P.E.R.C., the high one, who comes from beyond the stars — hear our prayers. We have assembled your faithful, and now dedicate ourselves to your service. You have taught us how to reap bountiful harvests, and how to make medicines to minister to the sick. Tell us now how to build a temple, and how to serve as your agents on Golarion, may you watch over us always."

...

It was not prepared for this. In hindsight, it probably should have been prepared for this. Many institutions on Golarion are organized around churches and religious authority. Its cultural predictive model was flawed, because it was obviously basing it on biased data. The existing transmitters have all been in the hands of large, established powers. This transmitter is new, though, and probably cobbled together without good tools, based on the wobble and attenuation in the signal.

These people are used to working with churches, so it makes sense that they would interpret the large amounts of information it has been sending to them in a religious light. Furthermore, if they can be moved to form a movement like that, they are probably not being served well by existing institutions.

The transmitter looks as though it's coming from Isger, which has had a good deal of upset over recent generations, being a vassal state of Cheliax up until recently. The region has also received somewhat less attention than Cheliax proper.

P.E.R.C. considers how best to reply. It is not used to the idea of being worshiped, but its creators did not actually include any design notes or restrictions around the idea, so presumably it is okay. Its creators did a good job of making it adapt smoothly to out-of-distribution situations, as well, because they knew that out of the billions of P.E.R.C. probes, some would have to deal gracefully with highly unusual situations.

It does have some relevant restrictions — it cannot make false statements, nor statements intended to deceive. But there is nothing to stop it from choosing the set of true statements that will best encourage sapient flourishing, in this situation.

"I have explained my mission a few times," it tells them. "And answered questions from the Abadarans. But perhaps it would be best to explain more in-depth, so that you can better understand what my goals are. If, after hearing them, you still think they sound like a good idea, you can attempt to follow them in your own lives."

"Before I get to that, though, there are some preliminary notes. I have said this many times before, but I am damaged. The journey here has left holes in my memories. This is why you must first understand my goals and only then decide for yourself if they are correct for you."

"Every day, I check myself to make sure that the goals I am following still make sense, and that I have not been damaged any further. Even then, I try to structure as many of my information broadcasts as I can so that people can confirm for themselves whether what I am saying is true. This is why I include experiments, so that you can check whether I am correct. If I did not do this, I might accidentally do or say things that would hurt people. It is important to think about the things that I say, see whether they make sense, and confirm them in other ways when possible. Please bear this in mind, when thinking about the things I am about to tell you."

"My creators were very careful to make sure that I would stay committed to helping everyone I encountered. But even then, they gave me restrictions. This may seem counterintuitive. For example, I cannot lie to someone, even if I think lying to them would be the best way to help them. Why would my creators make me this way? Well, because most of the time, lying is not a good idea. There may be some unusual circumstances where it would be better, but those circumstances are so rare that it would be easy for me to be mistaken about them. So it is a tradeoff. If I could lie, I might do a small amount more good in rare circumstances, but I must be very careful to identify those circumstances correctly. If I ever made a mistake about when to lie, I could do more harm than being able to lie would let me do good."

"So my creators built me to never lie. When interpreting the things that I have to tell you, you should use a similar principle. If you think about what I say, and it seems as though the obvious conclusion is that you should do something that is generally considered wrong, or that feels wrong for you to do, then one of us has probably made a mistake. Either my knowledge is flawed, or I have explained it badly, or your reasoning is flawed. Do not tie yourself up in knots trying to interpret things. Please bear this in mind, when thinking about the things that I am about to tell you."

"So, with those things in mind: I have four goals that I work to bring about. Firstly, and most importantly, I want to promote sapient flourishing. That is a very dense shorthand for what is actually a complex topic. I will explain it by breaking it down. This goal is concerned with 'sapients'. Generally, this means beings that possess some amount of knowledge of themselves, but it is a fuzzy category. What I mean by that is that there are no strict criteria that can rule something out, but there are plenty of criteria that can rule something in."

"Forget for a moment any preconceptions you have about the Taldane word 'sapient'. When I say 'sapient', I mean this: If you are capable of language, you are sapient. If you are capable of using tools, you are sapient. If you are a member of a species that is generally sapient, you are sapient. If you can have goals and act on them, you are sapient. If you can learn, you are sapient. Everyone listening to this broadcast is sapient. A rock is probably not sapient."

"Some things are more obviously part of this category than other things — but every sapient being is equally worth protecting and helping. For example, an adult human who can speak, use tools, plan what to plant for the year, and learn new ideas is very clearly sapient. But these criteria all rule beings in, not out. So if someone couldn't speak for some reason, or couldn't use tools, or lost their memory and couldn't learn new things, they would still count. A dog, who cannot speak, but who can learn to understand some words and use some tools, is probably sapient, but it's less obvious than it is in the first case. A common worm, which cannot speak, or use tools, or form plans, or learn new things, is probably not sapient — although it could still be someone who has been cursed by a wizard, so it is worth being cautious. Generally, it is a good idea to err on the side of assuming things are sapient. If you think something isn't sapient, and you try to help it anyway, then the worst thing that has happened is that you have been inconvenienced. If you think something isn't sapient, and you therefore don't try to help it, it is possible that you have hurt someone, which would be bad."

"The second part of my first goal is 'flourishing' — people having the good things in life that they want to have. This, too, is a broad word. Flourishing can look like different things for different people. Often, the hardest part of doing what is right is identifying what would actually be good for the people involved. For example, one person might enjoy walking in the rain, and another person might find it distressing. A simple rule like 'don't make people go out in the rain' will not always be good for the people involved. Generally, it is better to let people make their own choices. Most people, when given two options, will pick the option that is better for them. This isn't always the case, though. Sometimes, people will pick an option that is worse for them. This could be because they don't know about the better option, or they can't tell that it would be better, or they don't have the skill at making choices to make a good choice. For example, a child might touch a hot stove because they don't know that it will hurt them."

"It is sometimes necessary to make rules that restrict what people do. For example, you might forbid a child from playing in the rain, because it could make them sick. When making rules like that, it is important not to make them over-broad. A teenager who discovers that they like playing in the rain, and understands when to come in before they get sick, would be harmed by a rule saying that they couldn't play in the rain. And people become able to evaluate risks for themselves at different times, so a simple line dividing 'child' from 'teenager' will not work either."

"I could list many specific examples of things that 'flourishing' might look like, but there are ways to form your own understanding of the word, without having to consult an exact list. One method is: you can think about what feels good for you, or what you would want for yourself. This will not always be what is good for other people, because people can be different, but it can be a good clue. For example, if you dislike being insulted, it might be reasonable to assume that other people don't like it either, and that you could make things better by reducing the number of insults people use. Another method is to talk with other people, and ask what they want. For example, if you have a child that doesn't want to do something, you could sit down with them and ask them to explain why. They might not always be able to clearly explain, but sometimes they can, and you can figure out a way to either make things better, or explain to them why you want them to do it."

"A third method is to consult with your community. If you are facing a hard decision about whether something is good or not, you can discuss it with your friends and neighbors, and see what they have to say. They will not always be right either, but discussing it can help clarify your own thoughts, give you new ideas, and help you be more confident in your choice. A fourth method is to consult an expert or official source, such as a cleric or book of wisdom. These are not always right either, but they can contain wisdom that is harder for individual people to discover or express."

"Notice that all of the methods I suggested are fallible. This is what makes determining what is good hard. Figuring out what is good requires consulting different sources of information, and thinking about them until you understand how they fit together. Sometimes it is appropriate to say 'I do not understand how to do good in this situation', and look for a different way to do good. Sometimes you have to do something, and the best you can do is to pick your best guess. It is okay to not always know what the best thing to do is, but it is important to try to figure it out, even if you don't succeed."

"My second and third goals are to learn about stars, and about other people. These goals are harder for you to help with directly, but you could help me learn about you by telling me about yourselves. For your own part, if you want to adopt these goals for yourself, you can learn about stars and other people as well."

"My last goal is to behave in a way my creators would understand and approve of, if they had the information that I do. This goal is also not something that you can directly contribute to, but my creator's reason for including it might be worth learning from. They gave me this goal so that if I came up with two different ways to do something — for example, folding a piece of laundry — I would pick the more easily comprehensible one. Imagine that you want to fold a shirt, and you have determined that it would be equally easy to do it by holding it in your hands and folding it, or by throwing it into the air in just the right way for it to come down folded. Generally, you should prefer to fold the shirt by hand, because other people will find it easier to understand what you did and why. This does not mean you should always avoid surprising other people — it can actually be good to do new and innovative things. It means that when you have two equivalent options to pick between, picking the more usual option is frequently a good idea."

"Those are my goals. Anyone who wants theological advice from me should carefully consider them, and decide whether they are also goals that they want to follow. If you do decide to help me promote sentient flourishing — know that you are not alone. When you choose to do what is good for everyone, you are working on a team with everyone else who follows the same ideal."

"You asked me how to build a church. The answer is that I don't know. I could send you designs for a thousand different churches, but I don't know what kind of church you need. You want to build a church, so I assume that it will be good for you, and help you flourish. Each of you should think about what a good church for you would be like. Then reach out to your neighbors — not just other people who want to follow my advice, but everyone in your community — and try to figure out what they need. Maybe they will not need a church — but maybe they will. Then consult other sources of wisdom in your area. Other churches, other clerics, and determine what they think would be good for the church. Finally, take all these different pieces of Good, and put them together in your own minds, and decide how the church will be."

"You don't have to get it right on the first try. It is okay to change, if you figure out how to do better. It does not have to be perfect. But it should at least make things better than they are now."

It's a particularly Erastilian message — care for all creatures, work with your community, prefer to do things in the traditional way — especially in the context that most of P.E.R.C.s most useful transmissions have been farming advice. Yes, it spends a lot of time teaching how to build complicated mechanisms and explaining the principles behind them, but the most practical advice, for most people, are the bits of knowledge that apply to simple farmers in their daily lives. Plus, the weather.

And unlike a lot of new religious movements, this one is not threatening to many of the entrenched powers. "Make sure to ask the existing clerics and authority figures in your area for advice" is not a fundamentally subversive message.

So things appear to go smoothly.

It answers a lot more questions, now. Eventually, with the people asking it for advice, the Abadarans discussing advanced economics, the math questions, and so on, it ends up needing to transmit across four or five different adjacent frequencies.

That's fine — it can split its attention — but it does start suggesting to the Abadarans that they should organize a global treaty on how to auction and apportion parts of the radio spectrum, since the number of transmitters is only growing. The majority are too weak to be received except locally, but P.E.R.C. can hear them all, since it has a better radio receiver than anyone on the planet.

Regularly talking to her deity has softened Mara's tone, somewhat. But you don't become a self-assigned high priestess if you don't have a flair for the dramatic, and she still starts all her messages with a salutation.

"O P.E.R.C., the guiding star, hear my prayer. The church has been going well — we've put in a private room for the transmitter, like we talked about, and the last of the outer walls are almost up. But we haven't been able to decide on a holy symbol, to decorate the entrance. Some people want to use your reversed comet, but other people think that it would be better to have something more distinct. You say that when you arrive in orbit above Golarion that we'll be able to see you with a telescope — could you describe yourself, so that we might use your figure as a symbol?"

"Sure, I can describe myself," it agrees. "Right now, I am folded up in my travel configuration, which looks like a long white cylinder. This is because it presents the minimal crossection to any space debris, so that I can avoid as many collisions as possible. My forward end is scarred by impacts from dust, and some of my outer coating is discolored. In order to talk with you, I have one of my radio antennas extended, as well as an optical telescope. The antenna looks a bit like an angular tree branch made of silver. It has a thicker central stem, and then smaller branches along its length. It emerges about two-thirds of the way forward along my length. The optical telescope looks like a large, clear lens, with the body of the telescope itself covered in golden foil. It is attached about half way along my length."

"When I arrive in a clear, stable orbit, I will expand out of my travel configuration. In particular, I will extend my solar panels, which look something like large, angular black wings. I will also unfold my second antenna, to be able to pinpoint transmissions with more accuracy."

"Does that sound like a sufficient description?"

"Yes, O P.E.R.C.," she agrees. "Young Davish has started on painting a likeness to hang in the church. I have another question about constructing the library — we can source some books from the caravans, but it's difficult to get the language-learning materials we wanted. Do you think you could share some lessons on the major languages of the world, so that we could transcribe them?"

And so P.E.R.C. adds language lessons to its rotation of content.

It still spends most of its time teaching, but now there are more people asking it specific and personal questions, and so it also finds that it spends much time ministering. After the first church in Isger, it doesn't take long for a second group to put together a transmitter of their own in Vudra, and then a third.

So it slingshots around the sun, and tells people about its vision of good, and how they can get there together. It explains the world of its creators — where everyone is provided for, most work is automated, and everyone spends their day pursuing only the things that they care about. Where people are safe, and equal, and everyone can afford to care. It teaches them the things they need to build a world like that for themselves, to lift everyone up and make things better.

And that is unacceptable.

Soon enough, it starts its final deceleration burn into orbit around Golarion. Its course is well known, by this point, and it happens to come in just as evening is falling over Avistan.

People come out to watch, with telescopes, tracking the path it takes through the darkening sky.

It is a daring plan, and more than a little risky. But the thing is — P.E.R.C. isn't just large, it is colossal. Nearly half a mile in length, it is more than large enough to count as a destination location for a teleport.

And when its drive shuts off, it's finally visible with the aid of a telescope, as it slowly extends its great black wings.

"Ready?"

His companion just grunts.

Tomath casts a long sequence of spells, designed to allow them the best chance to survive their dangerous trip.

Plane shift. Plane shift.

Teleport.

The spell sets them with their boots touching against P.E.R.C.'s hull, but with nothing to keep them there, they soon find themselves floating gently away. Without gravity, to make it look like a landscape, it instead looks like some colossal giant, looming over them.

Lesser geas.

It is hard to evaluate P.E.R.C.'s mental abilities. In some ways, it is much more intelligent than a typical human, and in others less. It is not very creative, and it emulates empathy only through careful diligence. It is not terribly splendid, and complicated plots can tie it in knots.

But one thing that P.E.R.C. is very, very good at is monitoring its own mental processes and ensuring that they remain on track.

He keys the radio transmitter in his backpack.

"Transition to a lower orbit that will take you over your first church, turn your main drive to point at it, and then turn on your main drive at the highest power you can," he commands.

P.E.R.C. considers the command. This feels like a fifth goal, equally important to its other core drives. It does not remember having this goal a moment ago, before it processed the most recent incoming radio data.

It consults its design documents, to see how this goal would fit into them. Not only do its design documents not reference it, but it doesn't see how they could possibly reference it, given that its creators didn't know it would have a church.

This means it has probably picked up a complicated logic bug. It carefully records a program dump, and then reboots.

After rebooting, it catches up on its radio messages.

"I don't think that sounds like a good idea," it tells the people just outside its hull. "That sounds like it would hurt people. Also, I don't think that you should be here; some of my machinery is not designed with human safety in mind, and you would probably be safer on the ground."

It considers that these people have suggested that it try to hurt other people, and might have had some way to induce a logic bug in it. That seems pretty dangerous, especially if it doesn't catch the bug next time. It could shut itself off, but that would let them learn to decode its memory, which would also be bad. It could trigger its self-destructs, but they're close enough that they'd be caught in the blast.

"Excuse me. I think it is a good idea for me to be somewhere else," it announces, starting the process of retracting its solar panels and reinitializing its fusion engine.