GDP is a useful abstraction that can help guide policies. Do you have concrete examples of its unjust use that were supported by economists?

I don’t know any government that considers maximizing GDP as its primary goal.

Maximizing GDP doesn’t need to be the primary goal to as you say guide policies. There are plenty of policies aimed to increase economic growth as measured by GDP.

Economists however are on all sides of this issue, it isn’t some monolithic field where everyone agrees on even basic ideas.

What economists are on the side that GDP is a perfect measure that precisely captures the increase in well-being? I have never heard of one. If you look at the IMF website you will find a nuanced explanation of what GDP is and is not. For example, it states that

> It is also important to understand what GDP cannot tell us. GDP is not a measure of the overall standard of living or well-being of a country. Although changes in the output of goods and services per person (GDP per capita) are often used as a measure of whether the average citizen in a country is better or worse off, it does not capture things that may be deemed important to general well-being.

Tirades that when economists calculate GDP the human society is serving "abstractions" or the devil over the "real" and God is just fearmongering.

Again your taking things to unreasonable extremes, plenty of economists think GDP is good enough to be useful. Which means it’s informing their decisions or it wouldn’t be useful.

You can’t say measure X is useful, and it’s flaws are well known therefore it’s flaws are irrelevant. If it’s useful then it’s flaws are part of any decision made using it.

>plenty of economists think GDP is good enough to be useful. Which means it’s informing their decisions or it wouldn’t be useful

Yeah, that's precisely my point. It's informing their decisions.

>You can’t say measure X is useful, and it’s flaws are well known therefore it’s flaws are irrelevant. If it’s useful then it’s flaws are part of any decision made using it.

Measure X is useful, its flaws are well known therefore people who use it account for its flaws during the decision making process.

There are a lot more differences than that. You are communicating a subjective model of reality, one model of many, many models.

Within the context of a Model. Models that don’t capture the very large scale effects are useless and therefore not worth talking about. What’s left is models that used to capture large scale effects and all the smaller effects that where never captured by the model.

This sounds more like an argument for systems design. You can easily build models and meta-models that help navigate various scopes. For example the concept of the long tail is by definition a widely-scoped way of gaining leverage in a situation where smaller details are important.

Traffic control systems, computer hardware design...these all incorporate the same combinations of depth and breadth of thinking. I think it's wise to keep an open mind and ask whether it's really necessary to exclude a given model or entire set of them.

It’s not a question of excluding the model, it’s a question of the feedback loop where the model is used to both inform your decisions and validate they where correct.

Goodhart's law is an adage often stated as "When a measure becomes a target, it ceases to be a good measure"

> it’s a question of the feedback loop where the model is used to both inform your decisions and validate they where correct.

Who exactly are we criticizing for doing this? Seems a bit like a straw man argument tbh. I'm not even sure how that relates to the more general concept raised above, of a single model of reality being reliable.

If you want just one example, the IMF uses GDP data for critical decisions and to measure the results of those decisions.

At any granularity, knowledge consists of models in the consciousness of the thinker.

Direct observation exists alongside models. You may not be able to correctly interpret that observation, but it is still a form of knowledge.

This is true even if what’s being observed is by a simulated entity, the observation exists outside of it’s internal models and is indirectly related to things in the underlying reality. Ie, physical states of various bits of physical RAM.