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.
The investor should recognize that the more he succeeds in imitating the professional, the more likely it is that he wil...
Cycles will never stop. The rhythm of economic and market cycles is the most reliable feature of the investing world.
Think of life as a machine. If you can understand the cause-effect relationships that govern it, you can improve it.
An investor who has all the answers doesn't even understand the questions. Humility is essential for long-term success.
Does the company have a worthwhile profit margin? Growth without profit is meaningless.
We prefer investments where a catalyst exists to unlock value. Time is money - we want to know why and when value will b...
Fund returns tend to revert to the mean. Yesterday's winners become tomorrow's losers, and vice versa.
Owner earnings are the relevant item for valuation purposes — not reported earnings.
The concept of opportunity cost is the most basic idea in economics.
Cyclicals are companies whose sales and profits rise and fall in regular fashion.
To achieve satisfactory investment results is easier than most people realize.
Well-bought is half-sold. The most important thing is not what you buy, but what you pay for it.
Make believability-weighted decisions. Not all opinions are equal - weight them by the track record and expertise of the...
If you want to have a better performance than the crowd, you must do things differently from the crowd.
Does the company have a strong sales organization? Great products mean nothing if they can't be sold effectively.
The stock market is the story of cycles and of the human behavior that is responsible for overreactions in both directio...
Simplicity is the master key to financial success. The winning strategy is the simplest: own the market, keep costs low,...
Look at market fluctuations as your friend rather than your enemy; profit from folly rather than participate in it.
Know your circle of competence and stay within it. The size of that circle is not very important; knowing its boundaries...
Fast growers are small, aggressive new enterprises that grow at 20-25% a year.
The defensive investor will place his chief emphasis on the avoidance of serious mistakes or losses.
Skillful risk control is the mark of a superior investor. Great returns don't tell you much about risk - you need to kno...
Be radically transparent. Hiding things requires a lot of energy, builds barriers, and makes everyone worse off.
Search for value where others aren't looking. The best opportunities are often in the most unpopular sectors or countrie...
Does the company have an above-average research and development program that can continue to develop products that will ...
Most investors are primarily oriented toward return. We are primarily oriented toward risk. Return will take care of its...
Time in the market beats timing the market. Nobody can consistently predict short-term market movements.
We insist on a margin of safety in our purchase price. If we calculate the value of a common stock to be only slightly h...
I think it's important to reason from first principles rather than by analogy.
Stalwarts are large companies that grow faster than slow growers but aren't going to double overnight.
Explore core insights from different masters across investment topics