Right at the core, the mainstream has it backwards. Warren Buffett often quips that the first rule of investing is to not lose money, and the second rule is to not forget the first rule. Yet few investors approach the world with such a strict standard of risk avoidance.

Do not accept principal risk while investing short-term cash: the greedy effort to earn a few extra basis points of yield inevitably leads to the incurrence of greater risk, which increases the likelihood of losses and severe illiquidity at precisely the moment when cash is needed to cover expenses, to meet commitments, or to make compelling long-term investments.

Loss avoidance must be the cornerstone of your investment philosophy.

The strategy of buying what's in favor is a fool's errand, ensuring long-term underperformance. Only by standing against the prevailing winds - selectively, but resolutely - can an investor prosper over time. But for a while, a value investor typically underperforms.

Costs and liabilities are rarely overstated.

There is no amount of bad news that the markets cannot see past.

The way to maximize outcome is to focus on the process.