Theories, Laws, Models, Hypotheses, Facts, and Leppik’s Law

Leppik's First Law of Empiricism: The empirical support for a scientific theory is inversely proportional to the grandiosity of the name.

Corollary: Leppik's First Law of Empiricism can be applied to Leppik's First Law of Empiricism.

Science deals with two types of information: experimental data and observations about the world around us; and ideas which help explain, understand, and predict the data and observations. Of course, it is impossible to explain 100% of the data, since some data is inevitably wrong, but in some fields like physics and chemistry scientists have done an amazingly good job. In other fields, like economics, not so good.

Scientists use a lot of different names for their ideas: Laws, Theories, Models, Hypotheses, and so forth. Some of these names imply absolute inviolability ("Law") while others seem to imply more tentativeness or uncertainty ("Model" or "Theory").

But the scientific theories with the most data behind them and the strongest ability to explain observed facts also tend to have the most tentative-sounding names.

Let's take some examples:

Newton's Laws (physics): Newton's Laws are taught in beginning physics classes, and are very useful when calculating the motion of stuff that isn't too big, too fast, too small, too slow, too heavy, or too light. Outside this range, Newton's Laws have been replaced by the Theory of General Relativity and the Theory of Quantum Mechanics.

Theory of Evolution (biology): The most valuable tool in the biological sciences, the Theory of Evolution explains all kinds of observations, many of which were impossible to make before Darwin proposed the idea well over a hundred years ago. Evolution predicts that different fossils will be found in different rock strata, that different species will have many similar gene sequences, that isolated populations of a species will have observable differences from the main population, and many many other observations. Despite this scientific success, biblical creationists (or "intelligent design" proponents as they call themselves today) never tire of claiming that Evolution is "just" a theory.

The Standard Model (physics): The Standard Model is one of the most successful scientific theories ever, as measured by its ability to predict experiments to lots of decimal places. It predicts the behavior of elementary particles like electrons and protons, as well as ones with weird names like gluons, quarks, and pions.

The Law of Supply and Demand (economics): The law of supply and demand has been around for over a century, and basically predicts that as prices go up, demand goes down, and supply goes up (and vice versa). It makes a lot of sense in theory, but has been tested (at best) only in extremely limited circumstances. Supply and Demand assumes that everyone is at least mostly rational, an assumption which can be disproved by simply standing at the entrance to a Wal-Mart on the day after Thanksgiving. Supply and Demand also fails to explain such common behaviors as hoarding (demand goes up when price goes up) and loss adversity (refusing to sell something like a house or stock in a company at a loss, even if the market value is far below the price paid).

Hubble's Law (astronomy): Hubble's Law is the idea that the further away from us distant objects are in the universe, the faster they appear to be moving away. This is true in the broadest sense, but only if you look at lots of distant objects and sort of average them out. In reality, Hubble's Law should be Hubble's Rule Of Thumb (or if you prefer alliteration, Hubble's Heuristic). On a related point: Hubble's Constant turns out to be not so constant after all.

The Big Bang Theory (cosmology): The name sounds lighthearted, maybe even derisive (in fact, the name was originally coined by opponents of the Big Bang Theory as a way to mock it), but there's little scientific doubt today that the universe began a finite time in the past, and expanded from very small size and high density to what we observe today. In fact, about the only people who don't accept the Big Bang are the same people who don't accept Evolution, and for pretty much the same reasons. The Big Bang explains Hubble's Law, and is closely related to The Inflationary Model, which is a generally-accepted mathematical explanation of the large-scale structure of the universe.