It's only a theory?

The above phrase is one I have heard endlessly when discussing the theory of evolution with theists. The usual retort is "yes, but it's only a theory". Evolution is a fact. It has a staggering amount of supporting evidence, and is now well established within the scientific community.

The word theory has at least two very distinct meanings. One refers to a systematic body of knowledge that coincides with observation. This is it's more formal usage, as used within the scientific community, including the natural sciences. Other well known theories include Computational theory, Quantum theory and Chaos theory (to name just a few). These are well understood, and have considerable evidence to support them.

The other meaning of the word theory refers to a hypothesis, an idea or conjecture. This meaning of the word does not have the supporting evidence or systematic body of knowledge as the previous definition does. It is this interpretation of the word that theists jump upon when criticising Darwin's theory of natural selection. Whether through scientific ignorance, or to create deliberate confusion, theists continually attempt to dilute the usage of the word to mean the latter.

Extracted from the Oxford English Dictionary:

• Meaning 1 - A scheme or system of ideas or statements held as an explanation or account for a group of facts or phenomena; a hypothesis that has been confirmed or established by observation or experiment, and is propounded or accepted as accounting for the known facts; a statement of what are held to be the general laws, principles or causes of something known or observed.


• Meaning 2 - A hypothesis proposed as an explanation; hence, a mere hypothesis, speculation, conjecture; an idea or set of ideas about something ; an individual view or notion.

Meaning 1 is obviously the one which would accomodate evolution. Meaning 2 is the one identified by theists. There are more meanings for the word defined, but these are the two that are of interest to this discussion.

Several American schools have received demands from parents and/or school governers to have stickers added to the front of books on Evolution stating that "Evolution is just a theory". If you are using the stricter definition of the word 'theory' i.e. Meaning 1 above, then the preceeding statement is anything but a criticism, as any scientist would wholeheartedly agree that evolution is a theory, and a very good one at that. To state that evolution is 'just' a theory shows a lack of comprehension of scientific enquiry and the scientific process, as you have not understood how the word theory is used within science.

Theists simply cherry pick their targets, as they presumably have no demands to have similar stickers placed on books relating to mathematics, physicics or computing (Chaos, Quantum and Computational theories respectively).

Evolution is a fact. Period. It is backed by a huge body of supporting evidence including carbon dating, genetics and gene theory. No scientist would contradict its message. While there may continue to be new knowledge brought to light that allows scientists to review their understanding of some of its details, none of that takes away from the fact that as an over-arching theory, it is fundamentally correct.

The theory of evoluiton is both elegant and simple. It has stood up to one hundred and fifty years of criticism from theists. It is surely one of the most important theories ever discovered, having huge implications to our understanding of ourselves, and our place within the natural world.