Argumentative Theory is a concept proposed by Mercier and Sperber in, Why do humans reason? Arguments for an argumentative theory: "Abstract: Reasoning is generally seen as a means to improve knowledge and make better decisions. However, much evidence shows that reasoning often leads to distortions and poor decisions. This suggests that the function of reasoning should be rethought. Argumentative theory claims that the function of reasoning is argumentative. It is to devise and evaluate arguments intended to persuade. Reasoning is adaptive given the exceptional dependence of humans on communication and their vulnerability to misinformation. Skilled arguers 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."


From: A Conversation with Hugo Mercier: "Reasoning was not designed to pursue the truth. Reasoning was designed by evolution to help us win arguments. That's why they call it The Argumentative Theory of Reasoning. So, as Mercier and Sperber put it, 'The evidence reviewed here shows not only that reasoning falls quite short of reliably delivering rational beliefs and rational decisions. It may even be, in a variety of cases, detrimental to rationality. Reasoning can lead to poor outcomes, not because humans are bad at it, but because they systematically strive for arguments that justify their beliefs or their actions. This explains the confirmation bias.'" 


Chapter 5

What is Argumentative Theory?

Hugo Mercier, Cognitive Scientist,
French National Center for Scientific Research

Dan Sperber, Social and Cognitive Scientist; Central European University Budapest and French National Center for Scientific Research

Biased assimilation and attitude polarization: The effects of prior theories on subsequently considered evidence -  In a landmark experiment, Lord and colleagues (1979) asked participants who had been previously selected as being either defenders or opponents of the death penalty to evaluate studies relating to its efficiency as a deterrent. The studies given to the participants had different conclusions: While one seemed to show that the death penalty had a significant deterrent effect, the other yielded the opposite result. Even though the methodologies of the two studies were almost identical, the studies that yielded a conclusion not in line with the participants’ opinions were consistently rated as having been much more poorly conducted. In this case, participants used reasoning not so much to assess the studies objectively as to confirm their initial views by finding either flaws or strengths in similar studies, depending on their conclusion.


Janis (1972) recognized the fallacy of the reasoning in his work on group confirmation bias.  He observed that groups of academically brilliant government officials could make horrible mistakes that were actually compounded by their being in groups, he coined this group think.  People like Robert McNamara, Secretary of Defense under Kennedy and Johnson, and Donald Rumsfeld, Secretary of Defense under George W Bush, come to mind – people who, despite their academic brilliance, reasoned poorly, yet were able to persuade many by their false arguments.

Here’s a quote from Psychology Today, October 25, 2018:

Why People Ignore Facts, When it comes to reasoning, identity trumps truth.

Belonging to a particular political party can also shape our perception. In one study, participants were asked to watch a video of protestors. Half of the participants were told the people in the video were protesting the military’s “Don’t Ask, Don’t Tell” policy. The other half were told that the people were protesting an abortion clinic. Liberals reported saying the protestors were more violent and disruptive if they were told they were watching abortion clinic protestors, and the opposite was true for conservatives—the protestors at the abortion clinic were reported less violent and disruptive, even though everyone was watching the same video.  

Why does political identity shape our thinking and perception so dramatically? NYU psychology professor Jay Van Bavel explains the results of studies like these with his “identity-based” model of political belief: Oftentimes, the actual consequences of particular party positions matter less to our daily lives than the social consequences of believing in these party positions. Restated, our desire to hold identity-consistent beliefs often far outweigh our goals to hold accurate beliefs. This may be because being a part of a political party or social group fulfills fundamental needs, like the need for belonging, which supersede our need to search for the truth.

So, as Mercier and Sperber state about argumentative theory, and as Bavel just explained, people maybe not necessarily be after the truth but after arguments that support their views. Remember, synthisophy is integrating the wisdoms of history, based on fact and truth, into present culture.


Why do humans reason? Arguments for an argumentative theory Hugo Mercier, Dan Sperber, Behavioral and Brain Sciences (2011) 34, 57–111

A Conversation with Hugo Mercier [4.27.11] Introduction by: John Brockman

The Enigma of Reason, Hugo mercier and Dan Sperber, Harvard University Press, 2017

Why people Ignore Facts, in Psychology Today

Biased assimilation and attitude polarization: The effects of prior theories on subsequently considered evidence. Lord, C. G., Ross, L. & Lepper, M. R. (1979) Journal of Personality and Social Psychology 37(11):2098–109.

Victims of groupthink. Janis, I. L. (1972) Houghton-Mifflin.

Jay Van Bavel: The Human Mind Evolved in Groups - YouTube

Charles Lord

Irving Janis

Note that our own legal system of trial by jury is itself based on argumentative theory - arguments are presented by the lawyers of the plaintiff and defendant and the jury decides guilt or innocence.

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