Confounding Compounding

The Ice Ages and Why Warren Buffett is Rich

Warren Buffett’s net worth is around $84.5 billion. Of that, $81.5 billion came after his 65th birthday. Our minds are not built to handle exponential growth. We tend to think linearly, which makes compounding feel counterintuitive and almost magical.

The key to Buffett’s fortune is not just that he’s a good investor—it’s that he’s been a good investor for 75 years. Time is the secret ingredient that makes compounding work.

The Buffett Math

If Buffett had started investing at age 30 instead of 10, his net worth today would be approximately $11.9 million—99.9% less than his actual wealth.

His skill is remarkable. His time is what's made that skill pay off so spectacularly.

Jim Simons vs. Warren Buffett

Jim Simons, the mathematician who founded Renaissance Technologies, has compounded money at 66% annually since 1988—three times better than Buffett’s rate. But Simons’ net worth is 75% less than Buffett’s.

Why? Simons didn’t start serious investing until age 50. Buffett started at 10. The difference isn’t skill—it’s time.

"His skill is investing, but his secret is time. That's how compounding works." — The Psychology of Money, Chapter 4

The Ice Age Analogy

In the 1870s, scientists discovered that the Earth had experienced ice ages. The question was: what caused them? The answer turned out to be subtle changes in Earth’s orbit that slightly reduced the amount of sunlight hitting certain parts of the planet.

Here’s the key: the temperature change wasn’t dramatic. Summers just became slightly cooler—cool enough that winter snow didn’t fully melt. The next year, more snow accumulated. Then more. Over thousands of years, these tiny changes compounded into mile-thick ice sheets covering entire continents.

Compounding is Counterintuitive

The ice ages weren’t caused by dramatic events. They were caused by small changes that accumulated over time. This is exactly how compounding works in investing—and why it’s so hard for our brains to grasp.

We intuitively understand linear growth: if you save $1,000 a year for 30 years, you’ll have $30,000. But compounding is exponential, and our brains didn’t evolve to think exponentially.

Why This is Underappreciated

There are books written about economic cycles, trading strategies, and sector analysis. But the most powerful variable—time—gets the least attention because it doesn’t feel like an insight. It feels like stating the obvious.

But it’s not obvious when you see that 96% of Buffett’s wealth came after his 65th birthday. That’s not intuitive—it’s the magic of compounding over extreme time periods.

The Lesson for Everyone

Good investing isn’t necessarily about earning the highest returns. It’s about earning pretty good returns that you can stick with for a long period of time. That’s what makes compounding work.

A strategy that earns lower returns but can be maintained for decades will almost always beat a strategy that earns higher returns but burns out quickly.

Practical Implications

The Impatience Trap

Most people want to get rich quickly. The irony is that the surest path to wealth requires patience. Trying to speed up the process often leads to risks that set you back or knock you out of the game entirely.

Key Takeaways

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