"Many empirical controversies in economics are essentially disputes about whether or not certain variables constitute valid instruments" - Econometric Theory and Methods, Davidson & MacKinnon
"Many empirical controversies in economics are essentially disputes about whether or not certain variables constitute valid instruments" - Econometric Theory and Methods, Davidson & MacKinnon
Pretty broad statement. Some micro-economic theories, like the game theoretic models in auction theory, contract theory, mechanism design and behavioral economics are probably the most successful, accurate and impactful theories in all of social sciences, including psychology.
You may not realize how much your buying behavior, your salary, your interactions online and your use of technology are dependent on these models. But comparing their success and use to fields like sociology, management and even psychology, their track record is frankly amazing.
We already know that Macroeconomics amounts to modeling systems that do not aggregate meaningfully from these successful micro-models.
Saying economics is not a science based on this, is like saying physics is not a science because we still can not find a unified theory. Which is a pretty good analogy for a Macroeconomic model that forecasts GDP (aka, everything).
You've never looked at a macroeconomics model, have you?
Economics is complicated because it is modeling the behavior of human beings.
Math is easy, computer science is easy, modeling the collective behavior of humans is hard.