The Art of Thinking Clearly: Better Thinking, Better Decisions

See also Fundamental Attribution Error (ch. 36); Sleeper Effect (ch. 70); Confirmation
Bias (ch. 7–8); Information Bias (ch. 59); Personification (ch. 87); Story Bias (ch. 13)

---

EPILOGUE
The Pope asked Michelangelo: ‘Tell me the secret of your genius. How have you
created the statue of David, the masterpiece of all masterpieces?’ Michelangelo’s
answer: ‘It’s simple. I removed everything that is not David.’
Let’s be honest. We don’t know for sure what makes us successful. We can’t
pinpoint exactly what makes us happy. But we know with certainty what destroys
success or happiness. This realisation, as simple as it is, is fundamental:
Negative knowledge (what 
n o t 
to do) is much more potent than positive
knowledge (what to do).
Thinking more clearly and acting more shrewdly means adopting
Michelangelo’s method: don’t focus on David. Instead, focus on everything that is
not David and chisel it away. In our case: eliminate all errors and better thinking
will follow.
The Greeks, Romans and medieval thinkers had a term for this approach: 
via
negativa
. Literally the negative path, the path of renunciation, of exclusion, of
reduction. Theologians were the first to tread the 
via negativa
: we cannot say
what God is; we can only say what God is not. Applied to the present day: we
cannot say what brings us success. We can pin down only what blocks or
obliterates success. Eliminate the downside, the thinking errors, and the upside
will take care of itself. This is all we need to know.
As a novelist and company founder, I have fallen into a variety of traps.
Fortunately I was always able to free myself from them. Nowadays when I hold
presentations in front of doctors, CEOs, board members, investors, politicians or
government officials, I sense a kinship. I feel that we are sitting in the same boat –
after all, we are all trying to row through life without getting swallowed up by the
maelstroms. Still, many people are uneasy with the 
via negativa
. It is counter-
intuitive. It is even countercultural, flying in the face of contemporary wisdom. But
look around and you’ll find plenty of examples of the 
via negativa
at work. This is
what the legendary investor Warren Buffett writes about himself and his partner
Charlie Munger: ‘Charlie and I have not learned how to solve difficult business
problems. What we have learned is to avoid them.’ Welcome to the 
via negativa
.

---

I have listed almost 100 thinking errors in this book without answering the
question: what are thinking errors anyway? What is irrationality? Why do we fall
into these traps? Two theories of irrationality exist: a 
hot
and a 
cold
. The 
hot
theory is as old as the hills. Here is Plato’s analogy: a rider steers wildly galloping
horses; the rider signifies reason and the galloping horses embody emotions.
Reason tames feelings. If this fails, irrationality runs free. Another example:
feelings are like bubbling lava. Usually, reason can keep a lid on them, but every
now and then the lava of irrationality erupts. Hence 
hot
irrationality. There is no
reason to fret about logic: it is error-free; it’s just that, sometimes, emotions
overpower it.
This hot theory of irrationality boiled and bubbled for centuries. For John
Calvin, the founder of a strict form of Protestantism in the 1500s, such feelings
represented evil, and only by focusing on God could you repel them. People who
underwent volcanic eruptions of emotion were of the devil. They were tortured
and killed. According to Austrian psychoanalyst Sigmund Freud’s theory, the
rationalist ‘ego’ and the moralistic ‘superego’ control the impulsive ‘id’. But that
theory holds less water in the real world. Forget about obligation and discipline.
To believe that we can completely control our emotions through thinking is
illusory – as illusory as trying to make your hair grow by willing it to.
On the other hand, the 
cold
theory of irrationality is still young. After the Second
World War, many searched for explanations about the irrationality of the Nazis.
Emotional outbursts were rare in Hitler’s leadership ranks. Even his fiery
speeches were nothing more than masterful performances. It was not molten
eruptions but stone-cold calculation that resulted in the Nazi madness. The same
can be said of Stalin or of the Khmer Rouge.
In the 1960s, psychologists began to do away with Freud’s claims and to
examine our thinking, decisions, and actions scientifically. The result was a cold
theory of irrationality that states: thinking is in itself not pure, but prone to error.
This affects everyone. Even highly intelligent people fall into the same cognitive
traps. Likewise, errors are not randomly distributed. We systematically err in the
same direction. That makes our mistakes predictable, and thus fixable to a
degree – but only to a degree, never completely. For a few decades, the origins of
these errors remained in the dark. Everything else in our body is relatively reliable

---

– heart, muscles, lungs, immune system. Why should our brains of all things
experience lapse after lapse?
Thinking is a biological phenomenon. Evolution has shaped it just as it has the
forms of animals or the colours of flowers. Suppose we could go back 50,000
years, grab hold of an ancestor and bring him back with us into the present. We
send him to the hairdresser and put him in a Hugo Boss suit. Would he stand out
on the street? No. Of course, he would have to learn English, how to drive and
how to operate a cellphone, but we had to learn those things, too. Biology has
dispelled all doubt: physically, and that includes cognitively, we are hunter-
gatherers in Hugo Boss (or H&M, as the case may be).
What has changed markedly since ancient times is the environment in which
we live. Back then, things were simple and stable. We lived in small groups of
about fifty people. There was no significant technological or social progress. Only
in the last 10,000 years did the world begin to transform dramatically, with the
development of crops, livestock, villages, cities, global trade and financial
markets. Since industrialisation, little is left of the environment for which our brain
is optimised. If you spend fifteen minutes in a shopping mall, you will pass more
people than our ancestors saw during their entire lifetimes. Whoever claims to
know how the world will look in ten years is made into a laughing stock less than
a year after such a pronouncement. In the past 10,000 years, we have created a
world that we no longer understand. Everything is more sophisticated, but also
more complex and interdependent. The result is overwhelming material
prosperity, but also lifestyle diseases (such as type two diabetes, lung cancer and
depression) and errors in thinking. If the complexity continues to rise – and it will,
that much is certain – these errors will only increase and intensify.
In our hunter-gatherer past, activity paid off more often than reflection did.
Lightning-fast reactions were vital and long ruminations were ruinous. If your
hunter-gatherer buddies suddenly bolted, it made sense to follow suit –
regardless of whether a sabre-tooth tiger or a boar had startled them. If you failed
to run away, and it turned out to be a tiger, the price of a first-degree error was
death. On the other hand, if you had just fled from a boar, this lesser mistake
would have only cost you a few calories. It paid to be wrong about the same
things. Whoever was wired differently exited the gene pool after the first or
second incidence. We are the descendants of those