We've all heard Buffett's famous saying—"Be fearful when others are greedy, be greedy when others are fearful." It sounds very right, but how does it actually work in practice? I’ve found that most traders simply can't do it.

Let me share my own experience. Once, I had a position that had risen to a good level, and I was eager to take profits and lock in gains. As a result, I sold too early, only for the market to skyrocket, earning several times more. Another time, I forcibly resisted taking profits, hoping the profit would run further, but the market reversed unexpectedly, catching me off guard, and I lost everything. That’s when I realized the problem isn’t greed itself, but that I simply couldn’t tell when to be greedy and when to be fearful.

In markets like stocks, futures, and forex, the same situations happen every day. Buying at lows, the price rises to a profitable level, and then the market begins to correct. Should I sell or hold? Ten people will have ten different opinions. If I sell and the price goes higher, I regret it; if I don’t sell and it crashes, I start blaming my greed. Everyone can be a genius after the fact, but when actually in the market, nerves are tight, and it’s hard to stay calm.

I’ve observed many unsuccessful traders, and they all tend to have these four flaws: taking profits early, cutting losses quickly; adding to losing positions and holding on stubbornly; blindly chasing the market up and selling down; going all-in on a big position. The first two are driven by excessive fear; the latter two are pure human greed. These behaviors might occasionally win a few trades, but mostly it’s luck, and the final outcome is often a bigger loss.

The core of Buffett’s saying—"Be greedy when others are fearful"—actually requires a reliable trading system. Cut losses quickly, let profits run—sounds simple, but in practice, it demands clear entry rules, exit rules, and money management rules, then strictly follow them. With this system in place, you can truly overcome greed and fear, rather than being controlled by them.

Interestingly, human society has evolved from agricultural civilization to the information age, but human nature hasn’t changed in thousands of years. However, individuals can evolve. Professional traders succeed through practical experience and reflection, overcoming their inner fears and greed, ultimately becoming market winners. Most retail traders can never change this flaw because they lack the resolve for self-evolution.

So my advice is: don’t always think that "others are greedy, I am fearful" is some profound truth. Instead of guessing market psychology, respect the market, rationally view your trading state, and continuously improve your trading system within familiar and controllable boundaries. With rules and discipline, greed and fear will naturally cease to be problems.