Yesterday, I reminded my undergraduate economics students that modern economics, with its quantitative bias, is not about what is "fair" in life. While we can use economics to identify what isn't "fair" and how to better allocate resources, at its core economics is the study of efficiently allocating scarce resources. Math is not moral; it is an amoral aspect of economics that should be informed by philosophical inquiries.
For example, quantitative economics can answer when a person is "unproductive" and "inefficient" within the system. But, economics does not answer if it is moral to reallocate resources from the unproductive to either the currently or potentially productive members of a community. Raw numbers tell us the money spent on extending the last year or two of life might be best spent on educating the young. But is that the right way to approach problems?
Economic models do not tell us if stock market gains driven by low interest rates and stock buybacks funded by lower borrowing costs are morally right. What the models do tell us is that those with stocks do benefit from low interest rates more than those without equity holdings. The judgment of "fairness" is beyond the scope of economic models — fairness is philosophical and, inherently, political.
I'd argue that economics often leads us to the "worst" choices when we apply only mathematics and statistics in a manner that seeks to optimize capital and resource efficiencies. Instead, we must ask much larger questions about what we want, what we consider utility for ourselves and others.
With my biases of culture and experience, I'm a believer in markets, with their bubbles and flaws and asymmetrical transfers of knowledge. Central planning is "efficient" in theory… and lousy in practice.
Statistics alone can tell me what I "should" do to maximize whatever it is I want to maximize, but most of us want to make "inefficient" choices that conflict with what we consider our core values from time to time.
Eugene Fama has argued that markets are efficient over time. The trends are what we study, not the day-by-day, minute-by-minute human transactions. Days are unpredictable, but years or decades tend to follow trend lines. That is because all those unreasonable, irrational, emotional choices we make average out over time.
Markets, free and open, let me decide if I want to "waste" money on my pets, my cars, my games, my lawn. Markets let me decide to eat expensive meals I don't "need" and buy clothes (like ties) that serve no logical purpose. I've long theorized an economist could prove that the production and wearing of ties costs the global economy, diverting resources better allocated to other needs. But, I don't want to be told that I can't buy nice silk ties.
The math of behavioral economics studies we have done to predict what we will do. It doesn't tell us what we should do. The math of macro monetary economics doesn't tell us what interest rates should be, only what they will likely be in specific circumstances. Models are information. What we do with that information is much different question.
If you want to allocate a resource "fairly" you have to make a moral choice, a judgment, of what is fair and why. Mathematics cannot do that for you.