FTR, I'm not sure how this follows. Government exists because we agree to being governed. I exist because probably no one has agreed to kill me. Contracts exist, etc., etc. I mean, there is an imaginable universe where nothing has value, but that doesn't make this one any less real.

I wouldn't say economies are alone in their consensual reality, and government is a good example, but as ita points out, there's a way in which the economy is the most ephemeral example.

But I'm not saying that there's an imaginable universe where nothing has value, I'm saying that economies only exist when large portions of us can agree that the same thing has value, and that it has roughly the same value from day to day. Not to mention the fact that the universe in which none of us can agree on much of anything is at least as real as the universe in which we all agree that certain things have certain values. Those two realities bump up against each other a lot, and not always pleasantly.

Perhaps this is a bit pat, but people disagree about the value of things, but that actually doesn't mean that a system where people trade things for value is lesser or something. In every transaction we disagree about value-- I value that People Magazine more than $2, you value that $2 more than your People Magazine. I value that bushel of wheat more than my three chickens and you have the opposite opinion.

Not sure of the definitions and differences between causally and identically here

Causally means that one of the items is the cause of the other one (it is imaginary because...) and identically means both items are equivalent (it is imaginary, which is the same as...)

Okay, I get what you're asking. Unfortunately, I'm still not sure of the answer. Just because I'm making some bold declarative statements about economics doesn't mean I understand it or have any greater insight into the subject than professional economists.

I just dig talking about economics because of its semi-imaginariness. Actually, that's probably why I dig talking about government and religion as well, but somehow the shared hallucination seems the most striking aspect (to me) about economies.

that actually doesn't mean that a system where people trade things for value is lesser or something

I'm confused. Who said it was lesser?

In every transaction we disagree about value

I do disagree a bit here here. If I'm buying something for $5, it means I want the thing more than I want the $5. But I may think the thing's only worth $2.50, and I'm being fucked over. Or that it's worth $10, and I'm getting away with highway robbery.

There are two values there--one that makes the transaction possible (otherwise I'm not giving up the goods or the cash), and something we pretend is more objective.

I think the word value can be used meaningfully in both scenarios, but can get confusing when the scenarios are not clearly distinguished, so that's why I'm rambling.

I'm saying that economies only exist when large portions of us can agree that the same thing has value, and that it has roughly the same value from day to day.

I disagree that this makes them ephemeral. The modern global economy seems precarious because we've evolved an economy where you can literally trade nothing for nothing and end up making millions (which you can then use to buy real, tangible things).

But I don't know of any human society that does not exist on some level because people agree to trade things for other things -- economies develop because it is better to specialize and trade than to be self-sufficient.

In every transaction we disagree about value-- I value that People Magazine more than $2, you value that $2 more than your People Magazine.

It's not the minor disagreements about relative values involved in individual transactions that's threatening to any given economy, though. It's when we all lose faith in the value of one particular unit of trade that catastrophies happen. And it's intriguing because in many cases, nothing about the unit in question changed between the day when everything was fine and the next day when the economy was in ruins. What changed was people's confidence.

The problem is (IMO) some economists are much more confident that they should be given the degree of uncertainty in both their theories and data, and that in general a lot of economic theories are acted upon as though they are certain.

I think it's more of a case of people in power deciding what they want to do and then finding economists that agree with the policy to give it credibility.

And it's intriguing because in many cases, nothing about the unit in question changed between the day when everything was fine and the next day when the economy was in ruins. What changed was people's confidence.

An economy in ruins still exists, though -- the disappearance of a market (for tulips, comic books, or Enron stock) does not imply the disappearance of the larger system of supply/demand/exchange in which that market existed.

I disagree that this makes them ephemeral.

Fair point. Economies are real, and changes in them have very real effects. I think I would characterize them as ephemeral because it is possible for economies to not just collapse, but disappear entirely and need to be replaced by something else. Sometimes that's because of political calamity like war, or some natural disaster, but sometimes it's only because we stopped believing.

Something comes along to replace the economy in question, because the reality of our need to trade doesn't change, but we can disbelieve our ability to trade effectively out of existence for a time.

I think what Sean is trying to say is that economics is much more emo than government or law, and can trash its hotel room way faster. (Or, presumably, make a hotel room out of nothing way faster, although I think still slower than it can trash one.)

All abstractions can be metaphorized into rock stars, didn't you know that??