Of old. my people have divided the clouds by altitude. Near the ground we have fog. Many people don’t know it, but fog is actually a cloud called a “stratus” cloud. Stratus clouds can be higher than ground level, but not always. The other major type of low-altitude cloud is “cumulus” which are the puffy clouds you see in old storybook illustrations. Stratocumulus are a combination of the two: thin like stratus, but puffy on top like cumulus. In the middle range are the alto clouds: the altocumulus and the altostratus clouds that are wispier than the low-altitude clouds. These are the ones that give you haze in the summer. Up at the tippy-top are the high-altitude cirrus clouds, the cirrocumulus herringbone clouds and the wispy pure cirruses and the bad omen cirrostratus that make halos around the sun and the moon. Crossing the layers are the nimbus clouds, and the biggest of the lot are the cumulonimbus, also known as thunderheads.

And then there are the oddball cloud formations. Big ol’ mammatus clouds look like an upside-down pot of boiling water. Roll clouds look like someone’s laying turf in the sky. Funnel clouds mean someone’s about to go homeless, and a crazy lenticular makes you think that space aliens are about to land. Fallstreak holes are the noticeable lack of clouds in an otherwise overcast sky, like a giant had punched though a rotten piece of plywood. But whatever the variety, whatever the altitude, whatever the genesis, you can bet that a person on the ground will have a hard time resisting the urge to look at the clouds and daydream a little. Maybe dwarves are bowling. Maybe Thor and Zeus are sharing grappa and mead, maybe that’s one’s a dog and that one’s a mouse. Maybe we’ll all be swept up and out of Kansas to live in a magical land over the rainbow. I don’t know what the link between clouds and imagination are. Maybe it’s got something to do with distance or how the blood in your brain shifts around when your chin is tilted up. Whatever it is, it’s persistent. I sometimes wonder if dogs look at the clouds and see shapes they recognize.

Clay: “Smell is dogs’ most important sense. If they come up with stories, it’s probably through the nose, not through the eyes.”

Anika: “That’s a good point. Do you think they have stories though? I bet they do.”

Clay: “If they do, they probably aren’t stories we can understand very easily.”

Anika: “I’m not sure I always understand human stories every time.”

Clay: “That’s very grown-up of you.”

Following any large-scale environmental disruption, the populations quickest to return are almost always pestilent. Among the reasons pests are bothersome is their fantastic capacity to reproduce quickly and aggressively. Whether it’s an algae bloom or an overexuberance of midges, you can almost always count on an out-of-equilibrium ecosystem to fill up with troublesome critters. We don’t like apex predators because we’re fond of marauding tigers, we like apex predators because they’re a reliable sign that nature’s red teeth and claws are harmonious. No one wants to end up a bear’s lunch, but neither is it much fun to waste away from the depredations of parasites, plague, and the slow exsanguination of micropredators. Anika had grown up in bayou country, well aware of the folksy wisdom of how to minimize contact with the creepy-crawlies of the field and the sky. Clay had not.

Clay: “Damned bugs. Sorry. Dang bugs. They don’t seem to be bothering you.”

Anika: “I guess they like the way you taste or something.” Witch hazel was hard to come by out here and there was still enough summer left that sharing her dwindling supply meant being gnawed on in the thick of mosquito season. “Have you tried breathing through your nose?”

Clay: “Does that work?”

Anika: “Can’t hurt to try, can it?”

On level ground, in good weather, and reasonably unencumbered, it isn’t too much to ask a human in decent physical condition to hike twenty miles during daylight hours. Clay and Anika easily managed 25. That put them on pace to arrive about half a day ahead of schedule. Not ones to either dilly or dally, they took advantage of their progress to forage.

Anika: “Clay, do you know what osmium is?”

Clay: “Osmium? It’s an extremely dense, extremely rare metal. Why do you ask?”

Anika: “I once asked Sam where prices come from and he told me to think of osmium. I don’t get it.”

Clay: “So it’s supposed to be an economics koan or something?”

Anika: “A cone?”

Clay: “Koan. K-o-a-n. It’s something you’re supposed to think about deeply to create a deeper understanding.”

Anika: “Now I really don’t get it.”

Clay: “Me either. Hey, is this edible?” He held up a handful of purple berries.

Anika: “What, from that?” She pointed to a bush just a bit bigger than Clay.

Clay: “Yeah, you know what it is?”

Anika: “That’s elderberry. It’s fine, but don’t eat them raw. I didn’t think elderberries were in season yet. Let’s get as many as we can carry. Elderberry jam is great.”

Clay: “Okay. Do you have an extra bag?”

Anika: “I think so.” She rummaged around and eventually wrested an Army mess kit that was an antique when I was her age from the canvas bag that held it. She offered the bag to Clay. The two denuded the elderberry bush in short order and moved on to the next.

Clay: “I’m not sure I get it, you know, for sure, but maybe he was making some kind of scarcity point.”

Anika: “What?”

Clay: “The osmium. It’s an extremely rare earth mineral. It’s mined only as a byproduct of platinum refinement.”

Anika: “Yeah? So what?”

Clay: “Its density means that it has a number of very good military applications. Bunker buster warheads, for example. Osmium won’t ablate as it penetrates rock and concrete. It’s even more durable than depleted uranium.”

Anika: “They used to use osmium for weapons?”

Clay: “No, but that’s the point. Tungsten and old reactor fuel are also pretty scarce, but not nearly as scarce as osmium. To refine enough osmium for serious military use, you’d have to devote most of the military budget just for mineral exploration.”

Anika: “But it could be done?”

Clay: “Maybe. I don’t think anyone knows how many actual tons of osmium physically exist in the crust of the earth, but that’s almost never the question.”

Anika: “Just like the elderberries, right?”

Clay: “Yes, exactly. I see more bushes over there, and we could keep searching for more and filling up our pockets until we’re unable to walk another step, so our choices have to account for what we’re missing out on. If refining another ounce of osmium means giving up an infantry platoon, maybe it’s not worth it and maybe we should have gone with the tungsten instead. Sure, tungsten can’t penetrate a bunker as well, but the tradeoff is worth it.”

Anika: “So prices have something to do with what you have to give up?”

Clay: “It may even be more than that. Maybe one way to think of a price is to imagine that it’s sort of a conversation.”

Anika: “How do you mean?”

Clay: “Well, one person says, ‘I want you to do something for me,’ and that thing could be raising chickens and milking cows so that I can have breakfast, or it could be writing a piece of software, or it could be risking life and limb to build a magnificent skyscraper.”

Anika: “Okay, but I don’t see what that has to do with price.”

Clay: “Well, the other person replies, ‘how much do you want it?’ After all, some things are difficult to do, and they very often require convincing other people to do other things. If I want cheese on my eggs, I have to convince someone to make the cheese out of milk and rennet, but I also have to convince someone to raise cows and to grow cattle feed and to make milking machines and to do all the little things that contribute to cheese production. I have to convince someone that it’s worth their while to make a special kind of cloth.”

Anika: “So prices are this conversation?”

Clay: “Yes, and conversations happen between people. You can’t convince the planet to all of a sudden produce osmium from thin air, but you can convince people to put more effort into searching for it and refining it.”

Anika: “I think I see where you’re going.”

Clay: “If that’s true, then the only actual scarcity is people’s time and attention. That’s always been true I think.”

Anika: “You’ve obviously never gone hungry.”

Clay: “How do you mean?”

Anika: “Have you ever planted a field of corn only to have the entire thing ruined by bugs? Or lost a whole crop of potatoes and been forced to eat whatever grubs you could dig out of old rotten logs? That’s real scarcity, and it has nothing to do with any conversations.”

Clay: “Not immediately, no. One way to look at my old job as a hedge fund manager was that I used to buy and sell that part of the conversation. I used to trade in risk. When you plant a crop in May-”

Anika: “If you’re waiting until May to plant your crops, you have no one to blame but yourself when you go hungry in September.”

Clay: “Well, whenever. I’m not a farmer. When you plant your crops or set up your factory or start your political rebellion or whatever it is you want to do, there’s always some risk involved. There’s usually some uncertainty too and often some non-ergodicity.”

Anika: “What’s the difference between risk and uncertainty? And what the heck is ‘non-erocdicty?'”

Clay: “It’s got something to do with our knowledge of the underlying probability distributions. The point is, no one can tell the future. You can over-plant your land, over-engineer your factory, over-dig your mine, but the choice to avoid risk has a price tag, the same as anything else. What technology does, what cooperation does, what commerce does is to increase the available budget. And I think by ‘budget’ what I mean is the inverse of the amount of time and effort it takes to complete a task. Technology alters tradeoffs, but it can never eliminate them.”

Anika: “So what things are worth are a matter of how much time and effort went into making it?”

Clay: “I don’t think I was clear enough. That’s only half of it. Not even half. What things are worth depends on the alternatives for both buyers and sellers, and to a lesser extent other people affected by the sale. Alternatives include what else you could be doing with your time, but the heart of it nearly always has something to do with effort and attention and next to nothing to do with the abundance of raw materials.”

Anika: “Prices are about people, not about things?”

Clay: “That’s a nice way to think about it.”

Anika: “I’m not sure I saw how you get that from osmium, but I like that idea. So what do you suppose happened to everything now that no one makes anything big anymore?”

Clay: “If I understood that…”

Anika’s bag of elderberries slipped from her hand. Her eyes went wide, her jaw fell, and her index finger traced a horrified arc skyward.

Anika: “Uh…”

Clay glanced up. To the north, the witch-brew sky that heralded the End of the World was back again, sickly violet and phthalic hues spitting gangrenous tendrils towards the bilious earth below.

Clay: “Let’s take cover.”

Anika: “I hope Sam and Brigit are okay. That’s about where they should be by now.”

Clay: “Try not to think about it.”

The dull rumble of distant thunder played them a mournful lullaby as they tiptoed towards a restless night’s sleep. In Anika’s dreaming, faceless obsidian horrors defiled statues of dead emperors.

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