I get puzzled when I hear my graduate students confront me with the following: “You are saying something that totally contradicts what you told me about this problem x months ago”. Sometimes they get really upset about it, but I am at a loss! If I have indeed changed my point of view, I say, it is likely because I have been exposed to some new data that have changed my opinion. Isn’t it logical? In fact, I submit that we aren’t really scientists unless we constantly adjust what we think upon availability of new evidence that challenges our previously held views. But I have to confess: I am not always good at doing this.
While it is often possible to change one’s view, it is by no means a comfortable thing to do all the time. I would even go one step further and say that one of the common shortcomings of our reasoning is failure to reconcile new evidence that is in conflict with our strongly held views. This phenomenon is referred to as cognitive dissonance and it describes excessive mental stress when we are forced to hold two or more contradictory beliefs or ideas at the same time. The assumption is that we seek consistency between our expectations and reality. So we build a fortress of knowledge in a particular domain and consider everything there to be factual. When a contradictory piece of evidence is upon us, we have a natural tendency to dismiss it and find ways of convincing ourselves that there must be something wrong with the evidence. This is, of course, very dangerous. Here is a trivial example that happened to me before Christmas: I went to buy a new TV and I had a strong view that it is the plasma TV that I ought to get. When I was in the store and the sales rep listed several difficult-to-argue facts about the virtues of the LCD technology, I dismissed them and was looking for an excuse to brush off any argument aside (“this sales guy was kind of weird anyway, he was too pushy,” I said to myself). This unimportant encounter aside, I wonder how ready are we to accept evidence that destroys our cozy view or theory? There is a lot of food for thought here. So (I am talking to the students who run research projects), next time you come across an NMR spectrum that looks a bit odd and is nowhere near what you expected to get, do not put it aside and forget about it. Discovery is a study of conflict and I have seen it time and again in my own lab. The best students are able to get over cognitive dissonance and make interesting discoveries.