The Investment Masterclass · Lesson 7 of 19
Lesson 7 of the Investment Masterclass: the primal brain, why we do the worst things at exactly the worst times, and the surprising key to keeping it asleep.
Last verified: July 2026
Key takeaways
- Most foolish money decisions come from the primal brain: the old part of us built for the savannah, not for markets.
- It takes over at the worst times: crash means sell everything at the bottom, all-time high means FOMO-buy at the top.
- Everyone has a different sensitivity: greed, fear, impulsiveness, indecisiveness, denial. Knowing yours is part of the strategy.
- The surprising key: pick a strategy calm enough that your primal brain never gets triggered in the first place.
Investing is not so much about finding the perfect strategy as it is about sticking to the basics and not making foolish mistakes, as Lesson 6 showed. What we often forget: most of the foolish decisions we make come from the activation of our primal brain, the old part of the mind in charge of primal emotions and responses.
What is the primal brain, and when does it take over?
When you make plans, your rational brain is in charge: thinking, analysing, deciding. But sometimes the primal brain takes over, and usually at the worst of times. Stocks crashing? Sell, sell, sell. Bitcoin at an all-time high? The primal brain does not want to miss out, so it buys, at the worst possible moment. We end up doing all the worst things at exactly the worst possible times.
The cast of primal emotions is familiar: greed, fear (including FOMO, the fear of missing out), impulsiveness, indecisiveness, being overly optimistic or pessimistic, and denying obvious truths because they do not fit our narrative. All of these feelings are very real, and all of them can be incredibly powerful. They served us well 100,000 years ago on the savannah. Not so much in financial markets.
| Primal emotion | What it makes you do | When it strikes |
|---|---|---|
| Fear | Sell everything | At the bottom of a crash |
| Greed and FOMO | Chase whatever is at an all-time high | At the top |
| Impulsiveness | Act on the headline | Before thinking |
| Denial | Hold on to a broken story | Long past the exit |
What is the key to managing the primal brain?
The primal brain is hiding in the back of your mind somewhere, sound asleep right now, but ready to make a raging mess when the time is right. And everyone has a slightly different sensitivity: some of us are more susceptible to greed, others to indecisiveness or to being overtaken by fear.
So the somewhat surprising key to managing it is this: make sure it never gets triggered in the first place. Pick your strategy and portfolio in such a way as to never wake that part of you. Do you know you would freak out and do something foolish if your portfolio suddenly lost 30% of its value? Then do not choose a strategy where that can happen.
Why is knowing yourself an investment skill?
The better we, or our advisors, know which situations make our primal brain freak out, the better we can design strategies that avoid those situations entirely. The better you understand your inner game, the smaller the chance that you ruin your own strategy. The worst advisor is right there, in your own mind, and the goal is a strategy that never has to fight it.
That completes the three easiest wins in investing, all fully within your control: diversify, pick a strategy you can stick to, and stick to it, the longer the better. Everyone works on these, including the world’s best investors. The full curriculum lives on the masterclass hub.
Frequently asked questions
Why do investors panic sell?
Because in moments of stress the primal brain takes over from the rational one. It was built to escape danger fast, so in a crash it screams sell, which locks in losses at the bottom. The protection is a strategy calm enough that panic mode never activates.
What is the primal brain in investing?
The old, emotional part of the mind that handles fear, greed, impulsiveness and denial. It kept our ancestors alive on the savannah, but in markets it tends to trigger the worst decisions at the worst possible times.
What are the most common investor biases?
Fear-driven selling, FOMO buying at highs, impulsiveness, indecisiveness, over-optimism or over-pessimism, and denying facts that do not fit our story. Everyone has a different mix; knowing yours is half the protection.
How do I stop emotions from ruining my investments?
Do not plan to out-fight your emotions in the moment; plan so the moment never comes. Choose a risk level whose worst realistic drawdown would not push you into panic, and let the strategy carry you through the storms.
Next lesson: portfolio thinking, or why a good portfolio works like a football team. And if you want an advisor who designs around your inner game rather than against it, Alpian’s wealth advisory starts at CHF 2’000 at a FINMA-licensed Swiss bank.
This is Lesson 7 of 19
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