The more you know about your psychological biases, the better you can function in the volatile stock market.

Everyone has opinions and psychological biases.  However, people may not know their own biases.

The more you know about your psychological biases, the better you can function in the volatile stock market.

The entire market may be influenced by psychological reasons, not by fundamental reasons alone.

From an investment perspective, the bottom line is that the market will continue to fluctuate and give you solid opportunities every so often.

Value in the long run is determined by fundamentals, while short-term gyrations reflect market participants' psychological weaknesses, such as herding.  

Knowledge is the best antidote to making wrong decisions.

If you are a long-term investor, the rational thing to do is to make decisions based on long-term fundamentals of the business.