Begley, Sharon. "The Limits of Reason: Why Evolution May Favor Irrationality." NEWSWEEK August 5, 2010.

The fact that humans are subject to all these failures of rational thought seems to make no sense. Reason is supposed to be the highest achievement of the human mind, and the route to knowledge and wise decisions. But as psychologists have been documenting since the 1960s, humans are really, really bad at reasoning. It’s not just that we follow our emotions so often, in contexts from voting to ethics. No, even when we intend to deploy the full force of our rational faculties, we are often as ineffectual as eunuchs at an orgy.

An idea sweeping through the ranks of philosophers and cognitive scientists suggests why this is so. The reason we succumb to confirmation bias, why we are blind to counterexamples, and why we fall short of Cartesian logic in so many other ways is that these lapses have a purpose: they help us “devise and evaluate arguments that are intended to persuade other people,” says psychologist Hugo Mercier of the University of Pennsylvania. Failures of logic, he and cognitive scientist Dan Sperber of the Institut Jean Nicod in Paris propose, are in fact effective ploys to win arguments.

That puts poor reasoning in a completely different light. Arguing, after all, is less about seeking truth than about overcoming opposing views. So while confirmation bias, for instance, may mislead us about what’s true and real, by letting examples that support our view monopolize our memory and perception, it maximizes the artillery we wield when trying to convince someone that, say, he really is “late all the time.” Confirmation bias “has a straightforward explanation,” argues Mercier. “It contributes to effective argumentation.” . . .

http://www.newsweek.com/2010/08/05/the-limits-of-reason.html

Burkeman, Oliver. "This Column Will Change Your Life: the Power of Persuasion." GUARDIAN November 27, 2010.

Faced with any choice, especially big ones, we use our rational minds to identify reasons for and against, test them if possible, then do what seems most sensible. We know we're not infallible: numerous biases lead us astray, and we're horribly prone to rationalisation – that is, misusing our reasoning faculties to corral our emotions into line. But these are exceptions, we tell ourselves. After all, we're rational beings. That's what separates us from horses, or sardines, or Jeremy Clarkson.

Yet a forthcoming paper by the cognitive scientist Dan Sperber and the philosopher Hugo Mercier, "Why Do Humans Reason?", proposes a radical alternative. What if we evolved the capacity to reason not to get closer to the truth, but to persuade others (and ourselves) of viewpoints, regardless of their relation to truth? In evolutionary terms, the survival benefits of such a talent are obvious. Maybe – to borrow the analogy used by Jonah Lehrer, who highlighted the paper on his blog at wired.com/wiredscience – we don't go about life as quasi-scientists, as we flatter ourselves, but as quasi-talk radio hosts, devoting our reasoning energies to concocting arguments that feel persuasive.

This is speculation, but Sperber and Mercier show it makes sense of countless psychological quirks that otherwise seem mysterious. Lehrer cites the famous study in which people were asked to rate five jams previously rated by food experts. Non-experts ranked them the same as experts – except those who were asked to provide reasons, who diverged hugely, preferring jams that (according to expert opinion) were worse. Seemingly, they were casting about for convincing-sounding reasons – "Smoother jam is better", say – which threw them from their instinctive preference for the jams everyone else agreed were best. If reasoning is about truth-finding, this is bewildering, but if it's about generating fuel for persuasion, it makes sense. Rationalisation, from this perspective, isn't a failure of reasoning. It's what reasoning's for. . . .

http://www.guardian.co.uk/lifeandstyle/2010/nov/27/reasoning-gut-instinct-oliver-burkeman

Cohen, Patricia. "Reason Seen More as Weapon than Path to Truth." NEW YORK TIMES June 14, 2011.

For centuries thinkers have assumed that the uniquely human capacity for reasoning has existed to let people reach beyond mere perception and reflex in the search for truth. Rationality allowed a solitary thinker to blaze a path to philosophical, moral and scientific enlightenment.  Hugo Mercier is among the researchers now asserting that reason evolved to win arguments, not seek truth.

Now some researchers are suggesting that reason evolved for a completely different purpose: to win arguments. Rationality, by this yardstick (and irrationality too, but we’ll get to that) is nothing more or less than a servant of the hard-wired compulsion to triumph in the debating arena. According to this view, bias, lack of logic and other supposed flaws that pollute the stream of reason are instead social adaptations that enable one group to persuade (and defeat) another. Certitude works, however sharply it may depart from the truth. 

The idea, labeled the argumentative theory of reasoning, is the brainchild of French cognitive social scientists, and it has stirred excited discussion (and appalled dissent) among philosophers, political scientists, educators and psychologists, some of whom say it offers profound insight into the way people think and behave. The Journal of Behavioral and Brain Sciences devoted its April issue to debates over the theory, with participants challenging everything from the definition of reason to the origins of verbal communication.

“Reasoning doesn’t have this function of helping us to get better beliefs and make better decisions,” said Hugo Mercier, who is a co-author of the journal article, with Dan Sperber. “It was a purely social phenomenon. It evolved to help us convince others and to be careful when others try to convince us.” Truth and accuracy were beside the point.       

http://www.nytimes.com/2011/06/15/arts/people-argue-just-to-win-scholars-assert.html?_r=3&pagewanted=all

Mercier, Hugo, and Dan Sperber. "Why Do Humans Reason? Arguments for an Argumentative Theory." BEHAVIORAL AND BRAIN SCIENCES 34.2 (2011): 57-74.

Reasoning is generally seen as a means to improve knowledge and make better decisions. However, much evidence shows that reasoning often leads to epistemic distortions and poor decisions. This suggests that the function of reasoning should be rethought. Our hypothesis is that the function of reasoning is argumentative. It is to devise and evaluate arguments intended to persuade. Reasoning so conceived is adaptive given the exceptional dependence of humans on communication and their vulnerability to misinformation. A wide range of evidence in the psychology of reasoning and decision making can be reinterpreted and better explained in the light of this hypothesis. Poor performance in standard reasoning tasks is explained by the lack of argumentative context. When the same problems are placed in a proper argumentative setting, people turn out to be skilled arguers. Skilled arguers, however, are not after the truth but after arguments supporting their views. This explains the notorious confirmation bias. This bias is apparent not only when people are actually arguing but also when they are reasoning proactively from the perspective of having to defend their opinions. Reasoning so motivated can distort evaluations and attitudes and allow erroneous beliefs to persist. Proactively used reasoning also favors decisions that are easy to justify but not necessarily better. In all these instances traditionally described as failures or flaws, reasoning does exactly what can be expected of an argumentative device: Look for arguments that support a given conclusion, and, ceteris paribus, favor conclusions for which arguments can be found.

Download the paper here: http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1698090.