Warren Buffett's Two Rules

Rule 1: Never lose money. Rule 2: Never forget Rule 1. These two rules sound almost too simple to be useful. Understanding why they are the most important rules in investing requires unpacking what "losing money" actually means.

Why This Matters

Buffett's two rules are not about avoiding every paper loss — every investor experiences temporary price declines. They are about avoiding permanent capital impairment: situations where you lose money you cannot recover because the underlying thesis was wrong, the price paid was too high, or the business deteriorated beyond repair. The rules are a philosophical commitment to asymmetric thinking — obsessing over downside before upside, because mathematics works against you when you lose large amounts of capital.