Theory and Reality: Evolution is Both

Sent to The Star, Johannesburg Sat 12/11/2011 10:23, published published Thu 17/11/2011 minus the parts in blue as “Evolution is a fact, and that’s a fact”.

Bob Holcombe, in Readers' Letters of Friday November 11 ("Telling that his books have been taken off the shelves"), lambastes UFO-believers.  And so he should, because this is fringe stuff and highly debatable.

However, having deplored this deception, he tries a worse one of his own: To denigrate what he calls "unproven theories of macro-evolution" and promote the bible as good cosmology.

When someone says that evolution is "only a theory" he is not making a statement about evolution, he is showing his abysmal lack of understanding of basic science.

In science, some words have a more precise meaning than in everyday speech.

I am an engineer. If you tell me that you are "under pressure", I may ask "how many kilopascals?” Pressure is defined as force divided by area.  (All people live under pressure: About 100 kPa of atmospheric pressure)

Similarly, to a layman, a "theory" is something unproven, a guess, a conjecture.

When a scientist talks of a "theory" she means a coherent explanation of empirical phenomena, that is well-proven and logically consistent with observed facts.  It takes a lot of work by many scientists for a system to graduate from a "hypothesis" to a "theory".

Would Mr Holcombe like to tell us that Electromagnetic Theory (proof: electric light) or the Theory of Relativity (proof: the atomic bomb) is also "just a theory"?

The reason evolution is taught in schools is that it is fact: Proven beyond doubt to the satisfaction of all serious scientists.  The evidence is overwhelming that simple creatures evolved into more complex ones over millions of years.

Only those blinded by misguided "faith" in a literal interpretation of scripture believe –despite all evidence to the contrary– that the universe was created magically in six days.  Oddly, these same people question the existence of the Tooth Fairy and Santa Claus.

There are also scientific words for the biblical story of creation. They are "myth" and "fallacy".