We have no control over outcomes, but we can control the process. Of course, outcomes matter, but by focusing our attention on process, we maximize our chances of good outcomes.
Michael MauboussinEmphasising what's in your control allows you to adopt an attitude of equanimity toward luck. You've done what you can, and from there you have to live with the results - good or bad
Michael MauboussinPeople are, by and large, quite poor at judging correct absolute values but are astute about determining relative values. Psychologists call this coherent arbitrariness, which suggests that individuals are coherent when they compare prices on a relative basis but arbitrary when those prices are considered versus fundamental value.
Michael MauboussinEdge also implies what Ben Graham....called a margin of safety. You have a margin of safety when you buy an asset at a price that is substantially less than its value. As Graham noted, the margin of safety 'is available for absorbing the effect of miscalculations or worse than average luck.' ...Graham expands, "The margin of safety is always dependent on the price paid. It will be large at one price, small at some higher price, nonexistent at some still higher price."
Michael MauboussinA thoughtful investment process contemplates both probability and payoffs and carefully considers where the consensus - as revealed by a price - may be wrong. Even though there are also some important features that make investing different than, say, a casino or the track, the basic idea is the same: you want the positive expected value on your side
Michael Mauboussin