Perhaps one of the greatest achievements of Western Civilization over all others is the systemic body of scientific knowledge that has been collected over the past few centuries. Yet what kind of knowledge can be sufficiently called scientific? Certainly most would not venture to call astrology a science. I am indeed treading upon familiar problems within the Philosophy of Science, that of demarcation…
What makes a discipline scientific? Is it the methodology, the questions asked or is it the results? Does a science require a sufficient degree of mathematics? Does a field require a sufficient degree of explanatory power to make it scientific? Predictive power, or maybe reach a reasonable level of verification. What level of empirical work should the field pursue in order to cross the threshold required for science? How much control should the researcher have over the environment? Lastly, should the questions of the discipline be falsifiable? (Can any empirical question ever been sufficiently falsified?) It is because of these questions that I have come to question deeply the ‘scientific’ status of economics and to a lesser degree astronomy. (Although I have more to say about economics than astronomy)
I will go ahead and address each field separately.
The majority of economists go at great lengths in order to inform repeatedly of the scientific nature of their work. Every economics textbooks from the standard entry level Principles, through the intermediate level and graduate level starts chapter 1 with the declaration of the scientific status of economics. But why? Gregory Mankiw, a very influential Harvard Economist, says that it is because economists
“…use the data that history provides. Consider an astronomer studying the creation of galaxies or an evolutionary biologist studying the development of species. These disciplines, like economics, are primarily observational rather than experimental, but they are clearly scientific.” 
That is merely hoping that the audience will accept astronomy as a science and in so do liken the methodology of astronomy acceptable and similar to economics. However, this audience member calls into question the scientific status of astronomy as well, what now?
Most economists fall back upon Karl Popper’s notion of a science as a field in which its propositions are falsifiable. Most economists also believe that their work is empirical, that is describing something going on in the world. Some economists, such as those of the Austrian School shun empirical work for case studies. These Austrian reject the use of mathematics in the field and instead rely on pure reason. Yet when those economists are using pure reason to describe what is going on with prices and wages, inflation and unemployment, are they not talking about facts in the world? If they shun empirical work, then what is economics to be, metaphysics? This is an interesting question, perhaps for another post.
Returning to the previous inquiry, are the propositions of economics falsifiable? Certainly, the laws of Chemistry are falsifiable for there the researcher can control the environment and isolate the particular variable responsible for the causation in question. Can economics and other observational sciences say the same? I do not think so. At this point economists play apologetics and philosophers begin a quibble about the ontology of evidence and observation. Economists are quick to point out that theirs is a field of dynamic processes that are stochastic and thus they must rely on statistical and not deterministic models. Philosophers begin questioning observation and bring into the argument of quantum uncertainty and the effect of the observer on the experiment, thereby questioning the notion of control within the experiment. I do not find this convincing at all.
Without a reasonable, or rather at least sufficient, level of control over the environment the researcher encounters issues of verification of theory. Every phenomena encountered has an infinite number of explanations attributable to it. That is why Chemistry and Physics, when I say physics I mean everything but theoretical physics which is perhaps closer to metaphysics than empirical work, seek to control the experimental environment. They are experimental sciences rather than observational, those fields can influence the variables relevant to the causation at work. Without an experiment holding some important factors constant, how can the researcher adequately construct a theory that identifies the variable responsible for the causation in question? The observational sciences must then compensation for this by means of extra assumptions that makes the work further removed from empirical merit. At this point, the economist will falls back upon statistical inference and the background claim of ceterus paribus while the philosopher calls into question the assumptions assumed when controlling variables. The philosopher is perhaps also apt to remind me of the observation effect that is the observer influencing the results of the experiment by merely observing the experiment. To the former I merely point out the removed from reality nature of ceterus paribus. Changes in one economic factor always change other economic factors. Ceterus paribus is a fantasy, a removed idealization, much like perfect competition. Responding to the latter, the laws and effects of quantum reality are really a non-sequitor for our dryer-sized goods phenomenological experience.
So then, is economics a science? Well, sort of?
Price Theory, microeconomics, is I think the closest that we get to a science within economics. Microeconomics deals with individual actors, not the aggregate figures of macroeconomics. Price theory makes predictions about the choices that rational agents make when confronted with limited resources and unlimited wants (again some assumptions, but I venture to guess these fair assumptions) For the most part price theory makes good predictions, reliable predictions. There are of course instances where standard price theory falters. A sub-branch of microeconomics called Behavioral Economics is currently investigating those difficulties. The sub-field beings economics back in touch with empirical psychology in order to investigate the decision-making processes of economic agents. Microeconomics makes good predictions based upon a reliable methodology that yields results greater than that of pure chance reasoning.
Is the same true for macroeconomics? Is macroeconomics a science? No. The past 50 years of macroeconomic policy failure makes this type of economics not scientific. The sheer level of aggregation based upon individual human actions makes even statistical inference from observation unreliable. This coupled with the fact that the researcher cannot control the environment makes macroeconomics very unscientific. If there ever was a case for the uselessness of ceterus paribus, the prima facie example is macroeconomics.
What about astronomy, is it a science? Maybe, first let us consider the claims of Astronomy. First, that the universe is 14 billion years old, that the Earth is about 4.5 billion years old, and that the number of stars in the universe is roughly the same number as grains of sand on the Earth. These and other claims of what perhaps is hubris are substantiated by mainly observation and reliance of assuming the validity of physics. Astronomy assumes that the laws of physics on Earth are uniform throughout the entire universe, what a claim! Astronomy makes some of the greatest existential claims, that the universe is the sum of all matter while claiming at the same time that the universe is expanding…but into what? Is there a sign at the edge of the universe that states ‘Universe Ends Here.’ The methodology of astronomy relies heavily upon mathematics and the results of chemistry as justification for astronomical claims. Yet my issue with astronomy is the lack of empirical results relative to the claims made. Where is the empirical work to show the existence of black holes, of neutron stars, pulsars, and other galaxies? These are for all intensive purposes theoretical constructs with backing only from other theoretical assumptions from physics, chemistry and mathematics. We have no way to ostensibly point at the phenomena and measure it; Astronomy mainly bases its claims from the telescopic observation. The number of assumptions that astronomy makes are far too many given the poverty of empirical underpinning.
Normally a good philosopher, I am not a philosopher, gives definitions at the outset of his paper. However, science is a notoriously tricky endeavor to define! I am not sure as to what are the necessary and sufficient conditions for a field to be truly a science. Perhaps the following are some useful heuristics:
- That the discipline make good predictions.
- That the discipline employs a reliable methodology.
- That the discipline displays sufficient explanatory power.
- That the discipline controls the environment to a sufficient and reasonable degree.
- That the discipline has several active research programs.
Does this mean then that science is more like a continuum rather than a sharp break-off point?
Perhaps, but even to include astrology and phrenology on that continuum appears to me a front to the spirit of science. Have I diminished the value of economics or astronomy by taking the word science away from them? No, I do not fancy that at all. Philosophy is not a science by any means, but does that take away from the value of philosophy, I think not. (That said, I think a naturalized epistemology is best for philosophy, let’s drop the philosophical methodology) Perhaps given more empirical import to the said fields will I acknowledge those fields as truly capital S sciences.
*Oh, I posted the comic because I find it quite amusing.*
**I changed the original picture because this one is funnier**