FrameworkDecision principleInvestingValuationPsychology and behaviour
Price is what the market offers you today. Value is the separate question
Benjamin Graham · The Intelligent Investor
The idea
Graham's two ideas that survive the period detail are Mr Market and the margin of safety. Mr Market is a partner who every day offers to buy your share or sell you his at a price that reflects his mood rather than the business. You can ignore him, and you should unless the price is useful to you. The margin of safety is the discount to a conservative estimate of value that lets you be wrong and still do well. Together they make investing a two-step question: what is this worth, and what is the market offering, with no obligation to act unless the gap is wide.
Decide what a business is worth before looking at the price, then act only when the price is far enough below.
When it works
Any stock pitch, any conversation about whether a market move is a reason to act, and any valuation that starts from the price.
When it may fail
A conservative value estimate is still an estimate, and in a market that stays expensive for a decade the discipline can mean doing nothing for a long time. The idea protects capital; it does not promise opportunities.
How to use it
In a pitch, state your estimate of value and its basis before the current price. Then give the discount as a number and say what error in your estimate it would absorb. That is the margin of safety, stated as the interviewer wants it.
Where it came from
Book The Intelligent Investor · Benjamin Graham
What the source says. Margin of safety and Mr Market: read chapters 8 and 20 first and take the rest slowly, because much of the book is a period piece and the two ideas are the point.
Connected ideas
Says something similar
What is smart at one price is dumb at another: the two tests before a buybackA buyback creates value only with funds to spare and a price well below intrinsic value; above that price the same action destroys it.
Worth knowing first
A DCF is machinery for one sentence: value is the present value of expected cash flowsEvery cell in a DCF is a claim about future cash or about its risk; if you cannot say which, the cell should not be there.
Takes it further
Low risk and high uncertainty are not the same thingLook for situations where the range of outcomes is wide but the chance of permanent loss is small, because the market prices both as risk.
Worth knowing first
An edge usually starts as something you already understand better than the marketStart from an observation you can make and others cannot, then do the work to see whether the market already knows.
Concepts
Put it to work on L3VLUP
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