In any kind of complex system where the underlying outcome generating processes aren’t well understood – whether a company, or a society – the effects of changing the process won’t be well understood either. Unintended consequences must ensue.
Regular readers know how little time I have for macroeconomics. One reason is that it’s obsessed with the targeting of interest rates, GDP, inflation, unemployment, exchange rates, et cetera, as though such a thing was possible without unintended consequences. Since such variables are actually outcomes of a complex process, most macroeconomics seems to me to be an embarrassingly naïve study of outcomes which completely neglects process.