Have you ever wondered—how could such a brilliant mind like Newton get so badly caught in the stock market?

This happened in 1720. The South Sea Company, which had a monopoly on trade in the Americas and was backed by the royal family, drove the entire UK crazy. From nobles to commoners, no one could resist the temptation of "certain appreciation." In less than half a year, the stock price soared from £128 to £1,000, nearly an 8-fold increase.

At the time, 77-year-old Newton was head of the Royal Mint. He was initially quite rational. He invested £7,000, and when it rose to £14,000, he decisively sold, making a tidy profit. Surely, he should have stopped there, right? But the subsequent turn of events was heartbreaking—after selling, the stock kept rising, and people around him used this to buy mansions and estates. Newton couldn’t sit still. Watching the missed opportunity and driven by greed, he poured his entire fortune of £20,000 (his ten years’ salary) into the bubble.

Guess what happened next? The bubble burst right at that moment. When the Bubble Act was enacted, stock prices plummeted from heaven to hell, ending the year at just over £100. Newton lost all his previous gains and even lost his principal. He later famously said, "I can calculate the orbits of the planets, but I can't predict human madness."

This story is still repeating itself today. In the crypto market and traditional stocks, what drives prices has never changed—it's always a game of greed and fear. Ordinary retail investors who want to survive longer should follow one core principle: control your position size, never go all in. When the market hits its peak, that’s actually the best time to review your holdings and take profits. Keeping some cash on hand is true confidence. Before placing your next order, think about Newton’s lesson: even a mind of that caliber can stumble—maybe we should learn a bit of reverence.