Born to argue: the new theory of rational thought

A new theory has caused a storm among psychologists by suggesting that rational thought is a way to win fights and that faulty reasoning may actually be a good thing.

A pair of French social scientists have ignited a fiery debate in the world of psychology. In a new academic paper, published in the Journal of Behavioural and Brain Sciences, they question the nature of one of mankind's most fundamental qualities: the ability to reason.

Rational thought is what makes humans special. As far as we know, we are the only animals with the power of language and logic. We can imagine so-called 'counterfactual' scenarios, asking ourselves 'if this were true, what would the world be like' or 'if I do this, what will happen'.

Conventional wisdom says that human reason evolved to help us understand the world around us. For generations of philosophers, reason was a divine tool, a gift that allowed humans to cut through confusion and mystery and seek out the light of truth.

But this latest paper has set conventional wisdom on its head. In fact, say the paper's authors, reason has nothing to do with seeking the truth, or with being right. Instead, they argue, it evolved in the same way that teeth, claws or antlers evolved on other animals: as a tool for winning fights and achieving dominance.

A strong ability to reason makes us good at winning arguments, regardless of whether or not we're actually correct. It also makes us better at destroying the arguments of others. Winning arguments gives us influence and power, and that gives us a direct evolutionary advantage.

Many scientists are unconvinced by the new theory, but it does explain some mysterious flaws in the way human reason works. Psychologists call these 'biases' and they seriously harm our correct understanding of the world by distorting the way we weigh up and evaluate evidence. Until now, it was thought that these biases should have been squeezed out by evolutionary pressure, but under this new theory they actually make sense. Picking bad evidence doesn't get us to the truth but it works perfectly well in helping us to win a debate.

Reasonable doubt

So reason may be flawed, not by accident but because of its fundamental evolutionary design. As we grapple with the deep questions of existence, are we doomed to failure by the natural limitations of the human brain?

On the other hand, if this theory proves correct, maybe the lesson is simply to change the way we think. The traditional image of the philosopher is of a solitary thinker, seeking the truth alone. But if humans are so good at arguing, maybe we need to look at problems together. By attacking each other's points, and pointing out mistakes in the ideas of others, we may finally refine our own.

You Decide

  1. How important is reason and rational thought to you?
  2. Are humans better at finding answers alone or together?


  1. Find a classmate who disagrees with you about something, then try to convince them they're wrong. What strategies work best?
  2. How can we guard against bias in our thinking? Write a list of five mental steps you could take to make sure you were thinking fairly.

Some People Say...

“Instinct is much more useful than reason or logic.”

What do you think?

Q & A

Tell me more about these 'biases' then.
There are lots of different ones, but the most important is called 'confirmation bias'. It basically means that we naturally pay most attention to things that confirm our theories, while things that disprove our theories can easily pass us by.
And what difference does it make in the world?
A big one. Take any controversial question and look at the people arguing on each side – you'll find people who honestly believe in totally different answers to the same question. Confirmation bias leads to beliefs which look absurd to everyone else. There are still people, for example, who think that the world is flat.
It just shows how hard it is to get things right. There's even a philosophy, called 'scepticism', which says you can't really know anything at all.

Word Watch

The scientific study of the mind.
Basic and important
Counterfactual scenarios
A 'counterfactual' is basically a 'what if'. It's a scenario that goes against (or 'counter') to the established facts.
Conventional wisdom
Anything that's generally considered to be true.
Evolutionary advantage
Evolution happens when some characteristics in an animal give it an advantage over others. That animal then survives longer and has more children, which carry the advantageous characteristic into future generations.

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