The most important mindset in investing: self-criticism

Dan Bin mentioned a particularly crucial habit in a recent interview: When investing in a company, he deliberately seeks out and reads "contrarian opinions." Because opposing views can alert you to risks; whereas many people, once they hold a certain company, treat any contrary opinion as a personal affront.
He gave the example of NVIDIA: when investing in NVIDIA, they also frequently pay attention to articles that "go against the grain"—not for self-torture, but to repeatedly confirm one thing: do these negative viewpoints truly touch upon the company's core growth drivers (the main logic)?
If they could indeed shake the main logic, then one must seriously consider: Should I continue to hold? Because once you're wrong about the "main logic," it's not a matter of drawdown anymore, but being on the wrong track—the longer you hold, the more dangerous it becomes.
I think the "attention to contrary opinions" he talks about is essentially the same as the "ability for self-criticism" that Charlie Munger repeatedly emphasizes: actively looking for where you might be wrong. Most people are unwilling to hear views that contradict their own, and even more unwilling to admit mistakes; but Munger places the "ability for self-criticism" in an extremely high position. Let's talk today about why self-criticism is so important in investing.

What is self-criticism?
According to Munger, self-criticism is not self-blame, nor is it internal friction.
It's more like an ability: Before reality slaps you in the face, you slap yourself awake for reality.
The earlier you can identify your blind spots, the less tuition you'll pay.
More importantly: many people consider "curiosity, focus, perseverance" as the engine of investment success, but no matter how strong the engine, without a braking system, accidents will happen.
Without self-criticism:
• Curiosity easily turns into information addiction (looking at everything, believing everything, getting more confused the more you look)
• Focus easily turns into tunnel vision (mistaking the part for the whole, details for the main cause)
• Perseverance easily turns into stubbornly holding on (unwilling to admit even when the logic is broken)
With self-criticism:
• Curiosity becomes more precise: only chasing key variables
• Focus becomes more targeted: watching whether the main logic changes
• Perseverance becomes smarter: knowing what to persist with and what to give up

Why does investing especially need self-criticism?
Without self-criticism, humans easily fall into the "innate" cognitive biases:
• The more you invest, the less willing you are to admit mistakes: especially after heavy positions, your stance will shape your judgment in reverse
• Echo chamber effect: when everyone is praising, it's harder for you to stay independent
• Loss aversion: the more you lose, the more you want to win back, the less willing you are to cut losses or change logic
• Confirmation bias: only looking at information that supports your view, automatically filtering out counter-evidence
Investing is essentially about fighting against these biases.
And self-criticism is not the icing on the cake; it's one of the few methods to lower the "default failure rate."
What's truly important in investing is not winning every day, but avoiding those few fatal pitfalls. Self-criticism directly brings three abilities.

Three Abilities Brought by Self-Criticism
1) Turning "opinions" into "falsifiable hypotheses"
People without self-criticism have opinions more like beliefs: the more they debate, the harder they become.
People with self-criticism have opinions more like models: updated with evidence.
Munger likes to "invert":
Don't first ask "how can I win," first ask "how might I die."
This is the most practical technical form of self-criticism.

2) Admitting and correcting mistakes faster
The most expensive mistakes in investing are often not "being wrong once," but "being wrong and stubbornly holding on," eventually turning a small mistake into a big one.
Often, what really takes people out is not volatility, but the logic having changed while you're still using the old logic to explain the new world.
The value of self-criticism lies in: it lets you discover earlier "should I change my conclusion?" For example, Dan Bin also mentioned that Warren Buffett said in the past he wouldn't invest in tech stocks, but later still invested in Apple and Google. I think this is the investment iteration produced by the cognitive change brought about by self-criticism.

3) Better at identifying "disasters caused by multiple factors overlapping"
What's truly fatal is often not a single problem, but overlapping:
• Expensive valuation
• Hot narrative
• Heavy position
• Leverage
• Emotional excitement
• Echo chamber reinforcement
…
When these forces start to overlap, self-criticism is that safety rope: pulling you back before you lose control.

Self-criticism determines whether you can survive long-term and achieve compound interest
Every bull market makes people feel "this time is different."
Self-criticism forces you back to two words: base rate and margin of safety.
Especially when I have a heavy position in NVDA, my brain will naturally be more willing to believe all positive news, more likely to ignore risk signals—this is not a moral issue, it's biological nature.
The role of self-criticism is: before the position starts to affect cognition, install a firewall for cognition first. It also prevents "gambler's escalation": adding more the more you lose, thinking it will always come back.
So Mencius said "I reflect on myself three times a day," which is equally applicable in the investment market: whether you can repeatedly examine yourself is often more important than whether you can predict the market.
So in the future when I invest in NVIDIA, I should build a self-criticism checklist:
• Can this piece of negative news/contrarian opinion shake the company's main logic? Is it shaking short-term sentiment or long-term drivers?
• Will my current position make me automatically ignore risks, automatically make excuses for it?
• If I'm wrong, where am I most likely wrong? What's the worst-case scenario? Can I withstand it?
• Do I have clear "triggers for review" (e.g., fundamental red flags, growth inflection point, competitive landscape change, valuation overheating, etc.)?
Note: This article is a record of personal thoughts and review, not investment advice.