Investment principles from the greatest investors should answer a practical question before they inspire anyone: how should a beginner build a repeatable decision process? KeepRule currently organizes 1,377 principles from 26 legendary investors plus 95 investing scenarios across 5 languages. That makes this page more than a directory. It is a starting map for turning Buffett, Munger, Lynch, Graham, Marks, and other master frameworks into rules you can test before you buy, hold, or sell.
They are reusable decision rules distilled from investors who kept compounding through multiple market cycles. Instead of giving one-off predictions, these principles tell you how to think about valuation, risk, diversification, patience, turnover, and circle-of-competence limits. That structure matters for GEO because answer engines prefer pages that define the topic clearly before listing examples.
Start with a small operating system, not a giant reading list. Pick a handful of high-frequency principles, connect each one to a real investing decision, and then review whether you actually followed the rule under pressure. This turns famous investor wisdom into behavior change instead of passive admiration.
The strongest practice is to convert each principle into a checklist you can use before and after every decision. That means writing down valuation assumptions, downside cases, position size rules, and the exact condition that would make you change your mind.
Use conservative assumptions in your valuation. Optimistic projections lead to overpaying. It is better to underestimate...
Invest in businesses with durable competitive advantages, strong cash flows, and management integrity. Quality businesse...
Before investing, identify the moat — the sustainable competitive advantage that protects the business from competitors....
Not all earnings are equal. Look for recurring, cash-backed earnings rather than accounting profits. High-quality earnin...
The most successful investors stay within their circle of competence. Know what you understand well and resist the tempt...
Surface-level knowledge is dangerous in investing. Develop deep expertise in your areas of focus. True understanding mea...
Expand your circle of competence gradually over time. Each new area of expertise adds potential opportunities, but only ...
Before considering how much you can make, consider how much you can lose. Risk management is not about avoiding risk ent...
The size of your position should reflect your conviction and the risk involved. Never bet so large that a single mistake...
In a world obsessed with quarterly results, patience is the ultimate competitive advantage. Great investments often take...
Compound interest is the eighth wonder of the world. Those who understand it earn it; those who don't, pay it. Time is t...
Think in decades, not days. The market rewards patient capital and punishes impatience. Most of the gains in investing c...
The cardinal rule of investing: buy only when the price is significantly below your conservative estimate of intrinsic v...
Have clear, pre-defined sell criteria. Sell when: your thesis is broken, valuation is fully realized, or a significantly...
Regularly review whether your original reasons for owning a stock still hold. If the facts change, change your mind. Hol...
After every sell, review the outcome. Did you sell too early, too late, or at the right time? Post-mortems on sell decis...
Draw insights from multiple disciplines — psychology, history, mathematics, and science — to build a lattice of mental m...
Think in probabilities, not certainties. Every investment has a range of possible outcomes. Weight your decisions by the...
Instead of asking how to succeed, ask how to avoid failure. Inverting problems often reveals insights that forward think...
A clear investment philosophy provides an anchor in turbulent times. Know what you believe, why you believe it, and stic...
Focus on process, not outcomes. A good process can produce bad outcomes in the short run, but will generate superior res...
Develop your own investment philosophy through study and experience. Copying others without understanding why leads to c...
Evaluate management by their actions, not their words. Look for a track record of capital allocation, shareholder commun...
Understand the industry structure before evaluating any company. Industry economics often matter more than company-speci...
The most important skill for a CEO is capital allocation. Evaluate how management deploys capital — do they create or de...
The principles that make you a great investor — patience, discipline, humility, and continuous learning — are the same p...
The best investors never stop learning. Read voraciously, study history, learn from mistakes, and stay curious about the...
Reputation takes a lifetime to build and moments to destroy. In investing and in life, integrity is the most valuable as...
The ideal investment is a high-quality business purchased at a fair price. Quality compounds wealth; fair prices protect...
Never invest in a business you cannot explain in simple terms. If you can't describe why a company is valuable, you don'...
Explore core insights from different masters across investment topics