"Yeah. You coming too?" If they've retained what he's been telling them they'll understand the question but who knows if they actually remember any of it.

At least one of them gets it right away and says yes. The others follow suit, whether they would have gotten it on their own or not.

The main cafeteria is on the second floor, and is a huge mostly-open space with tables, chairs, and various food vendors milling about between the support beams. He won't recognize the origins of any specific dish, of course, but he can probably tell that the selection as a whole is aiming for about as much cultural and dietary diversity as it makes sense to offer an entirely human population. Food needs to be bought here, but his hosts are more than willing to pay for his.

"Wow. You guys do some interesting things with food. I've never seen anything like this." He assumes they'll get the tone even if not the words. He'll try some things. He mostly looks for ingredients he recognizes. He's assuming there won't be any honey in this universe.

They're happy that he likes it! 

There are lots of types of bread and cheese and fruit and meat, in addition to the complicated stews and omelettes and wraps with uncertain contents. There is also, if he looks for it, a dessert that consists of bread, unidentifiable nuts, and what appears to be honey. 

That's not what he expected at all. He gets a little of the honey dessert and a wrap and tries the local fruit.

"We call this honey," he tells the linguists. "Where's you get it?"

"Small animals make it. We call the animals bees."

Do they think thwilit are animals. Is that what's happening here. Maybe the thwilit are pretending so they don't get killed like the dragons?

"What are bees?"

"Bees - ah - a book, wait here, eat."

The linguist who's fielding this question returns, many minutes later, with a large illustrated book and another professor. The book contains, among many other animal drawings, a rather detailed diagram of a bee, with its various parts labeled. There's a picture of many of them living in a small wooden house on the opposite page. "These are bees."

"We have honey in Har. But not from bees."

"Huh! From what?"

"Birds. Little birds. They drink from flowers and then make honey. And they talk and do magic, they're people."

The linguist explains this to the other professor, who appears skeptical but intrigued.

If he's had the chance to finish eating while the linguist was tracking the book down, they've assembled a team of experts to listen to his explanation of sanitation.

He finishes and compliments the food, it's like nothing they have in Har.

"Great, are you translating for this or are we using magic?"

"Magic," says one of the other linguists, and the one who's gone to the effort to explain bees looks mildly relieved.

When he's sure he's done, they take him to a small lecture hall. Perhaps a third of the seats are full. There's a tablet and a book in a silver dish, both of them laid out on a desk at the front of the room. 

Imrainai is among the people gathered, allowed in for some combination of her medical knowledge and her previous experience with Mahan. She meets him at the front of the room. "They want you to talk. Can you use the tablet, if I show you?"

Oh. Great. The tablet. That lunch probably won't taste as good the second time.

"Yes. Show me."

"Not hard. Keep your hand on the tablet the whole time. Say exactly," she says, and gives him a not-overlong string of syllables. She demonstrates the use of a match, striking it on a rock, and then indicates the book before putting it out and offering him another. "Hand on tablet, say the words, then book. OK?"

This is a stupid way to trigger a spell, he doesn't say. What if he gets one of the foreign sounds wrong?

He says the words very carefully, pauses for a heartbeat, lights the match, then lights the book on fire.

"Is that right, is this working?"

"Yep! Just like that. We can all hear you, and you should be able to hear any follow-up questions they have. You'll want to keep the explanation to less than fifteen minutes, if that's feasible; more than that and you'll risk getting sick. It would be longer, but translating between this many people is more costly. Make sure you keep your hand on the tablet until you're definitely done. Spell ends immediately when you break contact."

He's been planning this lecture for a while, condensing it, going over it so there'll be fewer false starts and pauses. He takes a breath and starts talking. Quickly.

"There are seven causes of disease: poison, inheritance, not eating the right things, misshaped - let's say meat, being eaten alive by living things so tiny you can't see them, not living a healthy lifestyle, and being older than about sixty-two for humans. The being eaten alive is the kind I can do something about.

"There are different kinds of tiny creatures that like to eat different parts of people. Your body has ways of keeping them from eating you: your skin is in the way, your blood has things in it that eat them, your stomach is acidic enough to burn some of them. But sometimes they get past all your defenses and start eating. Then they breed and there are more of them eating you and then those breed too. These kinds of diseases usually pass from person to person or come from spoiled food or water that has sewage in it. Since they breed, diluting it doesn't work, it's not like poison. So just because water looks clear doesn't make it safe. When they don't come from food or water they usually come from a sick person's breath. If someone sneezes or coughs, if there's any spray and you breathe it in - then the disease is in you and if your blood can't get rid of it you'll get sick. Or if it lands on something you touch and then you touch food you're about to eat. And if it's none of those, the other way the little creatures can get a foothold is through a wound. If the skin is cut, then it can't keep anything out. That's why wounds rot.

"You can get these under control without me and my magic. Washing with soap made of fat and lye will get them off your skin. You should do that before you touch food or someone's open wound. You shouldn't breathe on wounds, the creatures are so small they can float in the air like dust. You can usually kill most of them with heat, so boiling all your water and cooking your food will help some, as long as no one touches it with dirty hands afterward. It has to be very cooked, though, not just warmed a little. You really don't want to rely on me for this. There's only one of me. There can be as many soapmakers as you need. I do have magic for this, but I have to be careful with it, because just killing all the little creatures in your body would kill you. That's because there are other little creatures that live inside you and help you digest your food. You have to be careful not to kill any of those. They're important.

"For the other kinds of disease - avoid lead. Avoid lead. Don't eat lead. Don't breathe lead dust. Don't put food or water in lead containers. Lead is poison. There are other poisons, too, but lead is slow and subtle so you wouldn't necessarily notice. Oh, and there's a metal that's liquid at room temperature that you should avoid, too. The really pretty one. Don't touch it.

"Do eat fruit and leaves and roots and meat. - Even though cooking is good for getting rid of some diseases, if you do it to all your plant food you'll have a disease where you get weaker and weaker and your teeth fall out. There's another disease if you don't eat meat, you can get anemia from that. Don't eat brains. Definitely don't eat other humans, that could give you holes in your brain. I don't know if you people even know enough about what brains do to know how bad that is but it's very bad. And, uh... don't have sick parents or be older than sixty-two, I guess."

He shrugs helplessly. "That's most of what I know. Any questions?"

A couple people in the audience - not Imrainai, she's not fast enough at writing - jot down everything they can from this speech in their notebooks. 

"Do you have any evidence for the claim that disease is caused by people being eaten by invisible creatures?" asks one of the men.

"There are some experiments you could replicate here to see if your diseases are the same. When one of our states started a public awareness campaign about handwashing and required doctors to stop touching people with dirty hands their infectious disease mortality dropped. Sometimes outbreaks of diseases - usually similar to cholera, usually not something like a sore throat - affect only people drinking from a specific water source, and only if they don't boil the water first. But Imrainai asked me to fix your fountains so if you see outbreaks like that now then I guess you'll know I'm wrong about how things work here. I don't have much better evidence because I've been told you don't do much scrying here and where I'm from that's how we found out."

A few people look at Imrainai. She smiles nervously at them. 

One of the men taps a pen on his paper thoughtfully. "That won't disambiguate between your model and one where diseases are caused by filth or by corpses and waste. The problem is, as always, attempting to keep the city clean under the weight of its own population, though the specifics of our approach must differ depending on what exactly we are fighting."

"How did you fix the fountains?" asks someone else.

"I enchanted them to kill things that are in the water that passes through them. You can check that with animals big enough to see. But I think you can tell the difference between waterborne diseases being caused by filth or being caused by something living, if you have humans to test it on. Since the creatures breed, dilution doesn't help like it would for a poison."

"Perhaps the universe's standards for cleanliness are higher than ours."

"Wouldn't be a high bar to pass, at this point."

"We can't test it on humans, not if we think we know the answer already - "

"Is it safe, having the fountains like that? We're not going to see children sticking a finger in and falling over dead?"