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by sudosysgen 2237 days ago
The law of gravity is actually not super simple. Relativistic gravity is an incredibly difficult and complex concept to understand, and the Newtonian law of gravity is simply wrong, enough that it has big impacts on the real world.

Whereas the law of supply and demand is not only preceded by a lot of assumptions that never are true in practice, and even with all those assumptions still has serious exceptions that apply to more and more and more goods as you move from theory to practice.

The laws of supply and demand are simply not useful for analyzing this market. Any attempt to use them will have to be accompanied by more classical incentive analysis and experiments that mean that ignoring it will give you better results than relying on it in this situation. Attempting to apply it gives you ridiculous conclusions, like that demand for housing is increasing everywhere in the world at the same time faster than supply, even when in practice supply is often greater than demand, leading to empty buildings, while prices still rise.

1 comments

> Relativistic gravity is an incredibly difficult and complex concept to understand

You're right, but the underlying rules are simple.

> leading to empty buildings, while prices still rise

That's still supply & demand. In this case, it is likely that the demand is rising fast enough that delaying renting the building will result in higher rents in the future for that building.

It's a chaotic system, and I mean that in the mathematical sense, where simple rules lead to complex (and counter-intuitive) behaviors.

No, the rules for Einsteinian gravity are not simple. Absolutely not. The underlying rules are not simple either. Simply calculating the instantaneous change in trajectory of an idealized two body system under Einsteinian gravity is an ordeal, and idealized bodies are a lot less useful under Einsteinian gravity than under Newtonian gravity.

I agree, it is indeed a chaotic system, and is even worse than that because there is no simple rule any agent is following.

If it is the case that not renting a building will result in higher revenue because rents will be higher in the future, then that building will not be rented out and neither will similar buildings, which will continue increasing rent at increasing speeds; and at the end rent will increase towards infinity. The simpler explanation is that no, not renting a unit does not lead to higher revenue, as leases are at most YoY, the YoY increase in rent would have to be over 50% for this to make sense, which isn't the case, and in fact actors in the market simply do not act as one can accept in any way, which is why you can't use supply and demand, or any basic economics for that matter.

For rent, for instance, you could have supply completely equal or even significantly higher than demand, as in there are significantly more buildings than tenants and more empty buildings that tenants looking for landlords, and still see prices increase. Indeed, if the landlords are coordinated or if they know that their tenants will not act rationally in the economic sense, you can simply have a system where all landlords continuously increase rent every year. And there is nothing that any tenant can do, so they have to pay increasing amounts of rent every year. In such a system, because commodities are not perfectly fungible, because actors are very far from fully rational, because knowledge from every actor is imperfect and because there are hidden costs both monetary and non-monetary, you can have a system where supply is higher than demand, and yet prices rise. No matter how you dice it, no matter which definition of supply and demand you use, the laws of supply and demand aren't being followed. Rental markets tend to follow this pattern, in even more complex ways with other effects that lead to supply and demand breaking down even more.

This is why trying to use macro-economic laws such as supply and demand without carefully going through each assumption behind them is a very dangerous mistake.

> The underlying rules are not simple either.

They are. By the principle of equivalence, it is just mapping the Lorentz frame onto curved spacetime.

pg. 386, "Gravitation", Misner

> actors in the market simply do not act as one can accept in any way

If other actors are acting irrationally, others can make money off of them. There are always smart people looking to make money off of irrational people, to the latters' detriment. Hence it is self-correcting.

> knowledge from every actor is imperfect

Imperfect knowledge is a common reason given for free markets not working. This is not true at all - another word for "imperfect knowledge" is "risk", and risk is certainly priced in everywhere.

> not perfectly fungible

Another word for this is "friction" and it is priced in to supply & demand, it is not separate from it.

> no matter which definition of supply and demand

I prefer not to make up my own definitions of terms in order to win an argument. I'll stick with the standard one.

> the laws of supply and demand aren't being followed

Your preconditions are incorrect, and hence your conclusion isn't, either.