Last night was a big debate between Bill Nye the Science Guy and Creationist Ken Ham. This was to help inform people that the science supporting evolution and how that refutes the “science” behind creationism. One of the key questions during the debate was around what would be required to convince Bill Nye that creationism was true and evolution was false. He said “Evidence” essentially. While, this is the ideal answer for a scientist, I find it unlikely. This, of course, isn’t a popular oppinion. It’s not that Bill Nye doesn’t believe that he would change his mind or that he would change his mind quickly, but it’s unlikely. People aren’t purely rational, in a purely rational world, yes that’s exactly what would happen. Even scientists have a serious problem with this. Scientists still suffer from the same sort of denial that global warming denialist, however, this impact is the largest inside of their field rather than outside.
Why do we know that this is true? According to Karl Popper whenever theories are incommensurate it’s unlikely that a leading theoriest in that field will switch to the new theory or paradigm. What does this mean? Well, if we think about scientific theories in terms of technology it will become easier to understand. Let’s look at jets and propellors for airplanes. It was clear in the early 50’s that jet engines were the way to go, but not all companies decided to pursue that type of engine. Instead these companies decided to continually tweak the capabilities of props instead. A similar reaction happened with sail technology and steam engines in this case sail techology was still more effective than steam, it took years before steam would catch up let alone surpass sail.
This similarly happens with scientific theories. What happens is that flaws start to appear that the theory cannot easily explain. For example, in the Geocentric theory planets would seem to track backwards over time and then begin to move forward. Theories about how these planets had small circles that would regularly appear through the course of their normal revolution around earth. The mathematics for this theory became increasingly complex and seemingly less realistic. The heliocentric approach reduced the complexity and eliminated the small circles and allowed for the eventual creation of Newtonian physics. However, whenever this started to break down and Einstein proposed relativity, it was largely ignored for decades. Essentially, it took until that generation retired for relativity to finally get accepted by the broader scientific community. This happens to scientific theories on a regular basis.
In fact, there are some pretty serious debates going on about the full mechanics of evolution. The original basis of the theory are still true, heredity, competition/pressure, and variety, however the nuances are being debated. For instance Richard Dawkin’s theories have started to fall a bit out of favor, while we’re learning that there are some things that we do in our lives that impact our genes. Those changed genes could be inhereted, which could change the next generation – this was Lamarcain to the core. However, Dawkins will likely not accept a different theory than the one he’s devoted to his life to. So, while to some extent it’s true that scientists will and do change their mind, it’s more likely that Science will change while individual scientist will take significantly longer if they ever do.