Sunday, July 1, 2012

Evolution is Just a Theory - Theory vs. Law

The focus should not be between whether or not evolution is a theory or a law, as in, "I'll take evolution seriously when to goes from a theory to a law." Instead the debate should be between the theory of evolution going from a theory to a disproven theory. The distinction is important and I'd like to briefly outline why.

The usage of the word 'theory' in science is quite distinct from our normal, vernacular usage. In science, the term means 'model' or 'explanation' that incorporates a vast body of knowledge.

Other 'theories' that demonstrate the usage of the word 'theory' in science: cell theory (that tissue is made up of cells), germ theory (diseases and colds are caused by microscopic bacteria, protists and viruses), atomic theory (matter is composed of atoms), theory of gravity (the force of gravity is the explanation for the orbit of stars, planets, galaxies and objects to the Earth), theory of heliocentrism (the Sun is the center of the solar system).

This confusion is the source of some fun internet memes:

A scientific 'law' is not an explanation or model, like a theory, it's a simple statement of this does that. Newton's laws are a go to example--"A body in motion will stay in motion unless acted upon by an outside force". It offers no explanation like a 'theory' would, only a relationship--this does that. If we were to write that law as a theory we'd have to offer some explanation as to *why* it happened that way--something about mass, inertia, Higgs-Bosons, etc.

So in conclusion, the Theory of Evolution could *never* become a law because it could never stop being an explanation as to why biology looks the way it does today. That said, it could become something else--a disproven theory. All it would take for the theory of evolution to be disproven is one fossil, one organism, one anatomical structure, one DNA sequence, one piece of evidence that could definitely disprove common ancestry of life. It shouldn't be shocking that the Theory of Evolution has never become a law, but it should be unbelievably shocking that the theory has never been disproven. The Theory of Evolution has been under constant fire from day one 150 years ago and it has never once shown a sign of weakening. It has only gotten stronger as more evidence has been produced.