Making the right decision is difficult, not least because our brains have many
inbuilt biases that lead us to behave in ways that defy logic and good sense. In
this extract from the New Scientist book, The Brain: A user's guide, we look atwhy that is and some of the most common cognitive biases to avoid.
Why clever people
make stupid decisions
New Scientist Books The Brain: A user’s guide
HOW intelligent are you? When it comes to making good
decisions, it doesn’t matter, because even the brightest
people can do ridiculous things. Clever people act foolishly
because intelligence is not the same thing as our capacity for
rational thinking – and that’s what matters when it comes to
making good decisions.
IQ tests, designed to measure general intelligence, are
very good at measuring certain cognitive abilities, such as
logic and abstract reasoning. But they fail when it comes to
measuring those abilities crucial to making good
judgements in real life. That’s because they don’t test things
such as the ability to weigh up information, or whether aperson can override the intuitive cognitive biases that lead
us astray. Understanding the factors that lead intelligent
people to make bad decisions is shedding light on society’s
biggest catastrophes. More intriguingly, it may suggest ways
to evade the stupidity that plagues us all.Gut reaction
Consider this puzzle: if it takes five machines 5 minutes
to make five widgets, how many minutes would it take a
hundred machines to make a hundred widgets? Most people
instinctively jump to the wrong answer that "feels" right –
a hundred – even if they later amend it to the correct one,
which is five.
When researchers put this and two similarly counter-
intuitive questions to thousands of students at colleges and
universities – Harvard and Princeton among them – only
17 per cent got all three right. A third of the students failed to
give any correct answers.
Here’s another one: Jack is looking at Anne but Anne is
looking at George. Jack is married but George is not. Is a
married person looking at an unmarried person? Possible
answers are "yes", "no", or "cannot be determined". Most
people will say it cannot be determined, simply because it is
the first answer that comes to mind – but careful deduction
shows the answer is "yes" (we don’t know Anne’s marital
status, but either way a married person would be looking
at an unmarried one).
We encounter problems like these in various guises every
day. And regardless of our intelligence, we often get them
wrong. Why? Probably because our brains use two different
systems to process information. One is deliberative and
reasoned, the other is intuitive and spontaneous. Our
default mechanism is to use our intuition. This often serves
us well – choosing a potential partner, for example, or in
situations where you’ve had a lot of experience. But it can
also trip us up, such as when our gut reactions are swayed by
cognitive biases such as stereotyping or our tendency to rely
too heavily on information that confirms our own■ Clear your mind.
Judgements are often
based on information
you recently had in mind,
even if it’s irrelevant.
For example, people bid
higher at auctions when
they are primed to ponder
the height of the tallest
person in the room.■ Don’t fall foul of spin.
We have an inclination to
be influenced by the way
a problem is framed. For
instance, people are more
likely to spend a monetary
award immediately if they
are told it is a bonus,
compared with a rebate.■ Don’t let emotions
get in the way. Emotions
interfere with our
assessment of risk. One
example is our natural
reluctance to cut our losses
on a falling investment
because it might start
rising again.■ Use facts. Don’t
allow your opinion to
cloud your analysis.■ Look beyond the
obvious.■ Don’t accept the first
thing that pops into
your head.How to be less stupid
>