I find commentary regarding open vs. closed minds to be vapid. For example, I saw this tweet:
Minds are like parachutes – they only function when open. -Thomas Dewar
I responded with this:
Minds are like castles under attack; they function well when the drawbridge is up, moat full, & the defenders are ready.
I’m a value investor. I do well partly because I am skeptical. I implicitly trust few opinions shared over the internet, or among my acquaintances. There are many out to bamboozle the naive.
Now, I’m not saying never believe anything. I am saying that you should test claims that you receive from others. What is the historical evidence? What are the biases of the writer? Few in investing write neutrally, so analyze the angle of the writer.
But after that, once you understand the biases, read the contrary data. They may know something that you or I don’t know. Compare it against other opinions, and ask those that would likely disagree for their opinions. Analyze, asking which opinion is most likely, or whether yet another opinion not yet imagined could be right.
This isn’t easy to do; it takes humility, which makes it hard for me to do, but the effort must be made.
Odd opinions must be made to jump high hurdles. We don’t want to be like those that believe things merely because they are odd. (I have known more than my share of those.) For investors, in prosperous times, oddity yields bad results. In unprosperous times, oddity yields volatile results. Some do incredibly well, and some very badly.
If someone proposes a novel investment idea to you, be wary. Few novel ideas pay off. This is not to say that classic ideas always do well, but the odds are skewed against novel investments.
In closing, be sensitive to your economic environment. There are no economic environments that offer unlimited potential. There are many that limit “normal” economic opportunities. Don’t force an overly optimistic view on the markets, or an overly pessimistic view.
Do your “due diligence.” Analyze your assets, and potential replacements. Then make businesslike decisions to buy and sell, after you have analyzed the situation in entire.