I have been reading David Romer’s Advanced Macroeconomics for some work I am doing and came across this. He is trying to explain why a particular equation doesn’t seem to capture the actual reality of the world. So he writes:

“There are other possible interpretations: the education and skills of the labor force, the strength of property rights, the quality of infrastructure, cultural attitudes toward entrepreneurship and work, and so on.”

And having noted all this in passing, he goes on his way.

To which I have added after a post in the comments which read: “Romer is referring to technology in Solow’s exogenous growth model and he does not simply move on. In fact, Romer devotes chapters 3 and 4 to a discussion of the drivers of technological growth.”

And indeed he goes on with an assembly of other factors of which the ones in the list are largely the specific ones ignored, such as the importance of property rights, say, or cultural attitudes, and the role of and attitude towards entrepreneurship.

If you cannot quantify some cause, so far as economics today is concerned it may as well not exist.