The volatility in the stock market AND bond market over the past few days has everyone concerned. Forget that the US market is still up over 10% for the year. We all tend to get very myopic in our vision when the stock market starts to waiver. Especially when bonds, which are supposed to protect us in down markets, are also losing money. It can make the thought of just selling everything and going to cash seem appealing. But as history reveals, that can be a very costly mistake.