No such thing as “settled science”
Posted by sanityinjection on September 9, 2009
How often have you heard the phrases “settled science” or “scientific fact”? They come up a lot in reference to issues like climate change, evolution, and abortion. Always the intention is to show that the currently prevailing scientific theory is correct beyond any doubt, and that anyone who suggests a contrary idea must be a crackpot.
This is contrary to the very nature of science. The success of science as a way of explaining the world around us is precisely due to science’s ability to revise theories in accordance with new evidence. Just as Einstein’s relativity replaced Newtonian physics, new discoveries continue to challenge our existing theories about life, the universe, and everything. Those who arrogantly insist on the infallibility of any scientific theory such as global warming or evolution are doomed to ultimate embarrassment when they turn out to be wrong.
A wonderful example of this comes to us from the science page of the Independent. Hominid skulls found in the Georgian village of Dmanisi are the oldest ever found outside of Africa, and they are challenging the long-held view that humans must have arisen in Africa and spread from there to Eurasia and other continents. This theory was, until recently, virtually universally accepted as fact. To suggest that one of the stages of human development (Homo erectus) evolved in Eurasia, as these fossils seem to suggest, would have been regarded as batty:
“The question is whether Homo erectus originated in Africa or Eurasia, and if in Eurasia, did we have vice-versa migration? This idea looked very stupid a few years ago, but today it seems not so stupid.”
Ultimately, it may or may not be shown that human ancestors went “back to Africa”. It has little impact for the average person today either way. The point though, is that the out-of-Africa theory is far older, more venerable, and had more evidence behind it than the theory of global warming does. If the former can be called into question by new evidence, the latter certainly can. So the next time that someone tells you global warming is “settled science”, feel free to treat the comment with the disdain it deserves.