Ratings agencies are highly conflicted, unimaginative dupes. They are blissfully unaware of adverse selection and moral hazard. Investors should never trust them.

Speculators are obsessed with predicting: guessing the direction of stock prices. Every morning on cable television, every afternoon on the stock market report, every weekend in Barron's, every week in dozens of market newsletters, and whenever business people get together. In reality, no one knows what the market will do; trying to predict it is a waste of time, and investing based upon that prediction is a purely speculative undertaking.

The risk of an investment is described by both the probability and the potential amount of loss. The risk of an investment-the probability of an adverse outcome-is partly inherent in its very nature. A dollar spent on biotechnology research is a riskier investment than a dollar used to purchase utility equipment. The former has both a greater probability of loss and a greater percentage of the investment at stake.

Here’s how to know if you have the makeup to be an investor. How would you handle the following situation? Let’s say you own a Procter & Gamble in your portfolio and the stock price goes down by half. Do you like it better? If it falls in half, do you reinvest dividends? Do you take cash out of savings to buy more? If you have the confidence to do that, then you’re an investor. If you don’t, you’re not an investor, you’re a speculator, and you shouldn’t be in the stock market in the first place.

Be sure that you are well compensated for illiquidity - especially illiquidity without control - because it can create particularly high opportunity costs.

Bad things happen, but really bad things do not. Do buy the dips, especially the lowest quality securities when they come under pressure, because declines will quickly be reversed.

Wall Street can be a dangerous place for investors. You have no choice but to do business there, but you must always be on your guard. The standard behavior of Wall Streeters is to pursue maximization of self-interest; the orientation is usually short term. This must be acknowledged, accepted, and dealt with. If you transact business with Wall Street with these caveats in mind, you can prosper. If you depend on Wall Street to help you, investment success may remain elusive.