Here's a study that rings true: People tend to hold more extreme positions on complex policies when they don't know very much about them, according to a research article in the academic journal Psychological Science. Having people attempt to explain how the policies work is enough to reduce their sense of certainty, as well as the extremity of their political positions.

Research subjects stated their positions on six political policies on a scale from strongly against to strongly in favor, and then rated their understanding of the policies. After that they were asked to provide a detailed explanation of two of the policies. "Attempting to explain policies made people feel uncertain about them, which in turn made them express more moderate views," the researchers concluded.

In contrast, people didn't seem to change their minds much when they were simply asked to explain why they felt they way they did about a policy.

David Fuller's view I though the article was interesting but it did not cover behavioural aspects of market views.

In my opinion, as investors we often have stronger but perhaps less objective views about a position we hold, or have held recently. In other words, it is often easier to be objective if we carry no baggage in the form of either our own positions or a view that we have stated.

So how can we stay objective about a position in which we also have an emotional interest? It is not easy but price charts can be a useful reality check.