Motivated reasoning and confirmation bias

The idea that emotions can affect reasoning has a long and controversial history in psychology. One of the most significant ways humans warp their information processing and decision-making is known as motivated reasoning.

Motivated reasoning is a mechanism of reasoning by which people access, construct and evaluate arguments and data in a biased way, in order to arrive at a preferred conclusion. It is called “motivated” due to the fact that information is interpreted so that it can accommodate some pre-existing belief. In other words, we like to think things are the way we prefer them to be. Due to this, we “convince ourselves” to believe things are that way. We distort our assessment of the evidence we have to reach the conclusions we like. We don’t do this on purpose; we do it unknowingly due to this cognitive bias.

Thus, motivated reasoning leads to denying, or avoiding the examination of unwelcome information. In contrast, it leads us to, much more easily and with much less analysis, accept the data and arguments that fit our wishes, desires, preferences or beliefs. That is, it leads us to have a confirmation bias. Confirmation bias is the propensity for people to look for what confirms their beliefs and ignore whatever contradicts them, without concern for their truth or falsehood.1

Findings about motivated reasoning and confirmation bias form the cornerstone of a key conclusion in modern psychology: reasoning is suffused with emotion.2 Data, facts and ideas elicit positive or negative feelings. In fact, those feelings are elicited more rapidly than the conscious thoughts prompted by such data, facts and ideas.3 When received data contradicts our pre-existing beliefs, it is interpreted as threatening to our views, and ultimately, to our identity and our sense of self. Thus, humans are adept at blocking or dismissing information perceived as threatening and accepting information perceived as friendly.4


Motivated reasoning or why both sides in a discussion always think they are right

Motivated reasoning can play its part in everyday situations. For instance, imagine yourself watching a soccer game on TV. In a crucial moment of the game, your team gets fouled: “it was a penalty!” you claim, but it is not sanctioned by the referee. Then, you will probably protest against the referee, disregarding her abilities and objectivity. You may think (or even shout) that “the referee has been bought”, “the referee is corrupt”, or “the referee is an incompetent who does not have the slightest idea how to run a soccer game”. Every time the play in question is repeated on TV, you will find elements that prove that the referee was wrong and your team was fouled. On the contrary, you may not be willing to recognize any evidence that might prove that the foul was not sanctionable and that the referee may have been right.

However, if the same happens later in reverse, your reasoning might be diametrically different. The referee does not sanction a foul committed by your team against the other, and you suddenly forget all the dismissive ideas about the referee that you had before. Now, you congratulate the referee’s accuracy that has proved that the play was not sanctionable. Because we want our team to win, we can easily accept and even actively look for information that confirms our desires, but we will not accept and may even be dismissive in scrutinizing any information to the contrary.

Motivated reasoning has been extensively studied. In a classic experiment, researchers led participants into a room and had them play a history trivia game. Before starting to play, the researchers made the participants watch someone else engage in the game. Some participants were told that person would later be their partner. Others were told that individual would later be their opponent. Participants did not know that they were actually watching an expert, who correctly answered every single question. The researchers found that participants who had been told that the player would be their opponent attributed her accuracy to luck and dismissed her abilities. In contrast, participants who were told that the player would be their teammate highlighted her skills. Although all participants had seen the same performance, they arrived at divergent and incompatible assessments of it. This suggests that participants selectively ignored or accepted information, depending on whether or not the evidence satisfied their own pre-existing concerns.5


Motivated reasoning about animals

Our disposition to scrutinize ideas and events more carefully if we do not like them than if we do also affects the way we think about animals. Animals used for food offer a good case to show how and why facts are discarded in favor of some form of motivated reasoning.

It is widely known today that animals are sentient beings capable of positive and negative experiences. Nearly all the external signs that lead us to infer pain in other humans can be observed in other animals, especially in mammals and birds. Like humans, animals can grimace when they suffer, groan or yelp and try to avoid the source of harm. What is more significant: animals of most species have centralized nervous systems. This physical structure and its associated functioning make it possible for animals such as them and us to feel and have other conscious experiences. This is not the case, however, in the case of plants.

However, because many people have a positive attitude towards animal exploitation (as they enjoy using animal products and services), they doubt that animals are significantly harmed by their exploitation. This is probably not mere skepticism about the capacity for sentience of cows or chickens, but rather a form of motivated reasoning that leads people to claim that “animals cannot talk, so they cannot experience pain in the same way humans do”, “cows have fewer mental capacities than animals such as cats and dogs”,6 or “plants can feel too, so there is no way to eat without harming others”.

Although there is conclusive evidence against these claims, these beliefs manage to garner passionate support. Plausibly, this is because animal products are a part of the culinary culture of almost every society. Humans do their best to sustain a positive self-image and to protect their cultural practices from perceived threats through cognitive mechanisms such as motivated reasoning.

The lives of animals living in the wild can also be perceived through motivated cognition. When people realize the threats and tremendous harms faced by animals living in nature, a common reaction is claiming that these animals can cope with their suffering better than domesticated animals or that the continuous threats of injury, hunger, pain and fear make them more insensitive to it. However, those animals have nervous systems that are not substantially different from ours or from domesticated animals’. In addition, the fact that such difficult situations are constant and familiar to animals living in the wild does not mean that they do not suffer – it just means that they endure these difficulties not because it is easy for them but because they have no choice (see more).

Being aware that we tend to look only for what confirms our beliefs (confirmation bias) and not to scrutinize contrary ideas (motivated reasoning) helps us to understand why people can take such a harsh and immutable stance against animals’ interests. In addition, it has been proved that hypotheses that involve personal moral commitments are especially prone to show bias and motivated reasoning.7 However, the phenomenon of motivated reasoning also shows that facts related to animal sentience and moral positions can elicit an emotional threat reaction. In that sense, it has been pointed out how important it is to frame our message about animals’ interests as a concern compatible with the core values of our culture.8


Motivated reasoning and confirmation bias: Can we think straight about our activism?

Activists are not exempt at all from motivated reasoning and confirmation bias, as these are mechanisms in which humans commonly process information. The tendency to search for what confirms people’s own beliefs and ignore everything that contradicts them serves to satisfy the human need to think well of themselves, to avoid stress when confronting undesirable information and to be accepted by others.9

Two major classes of motives have been shown to bias reasoning. The first ones concern impression management and smooth interaction with other people. The second class of motives refers to mechanisms triggered by cognitive dissonance and threats to the validity of one’s cultural worldview.10 These motives can direct our world and evidence interpretation, and appear both when people are arguing and also when they are reasoning proactively from the perspective of having to defend their opinions.

However, humans normally ignore that their reasoning is shaped by their previous experiences and preferences, leading them to dredge up evidence to support their ideas and dismissing data that contradicts them. In this sense, when activists -like common people-face a demand for a justification on their position, it is easy to become a “lawyer”, trying to build a case, rather than a “judge”, who searches for the truth.11 The above means focusing on presenting argument after argument, not wavering if one’s own point of view could be wrong, even when the arguments of the other party have strongly proved to be right.

As motivated reasoning can distort evaluations and attitudes and also allow erroneous beliefs to persist, it is necessary to maintain a mindset intended to survey the landscape as accurately as possible instead of going after arguments supporting our views, not tying self-worth to our own opinions. Some researchers call this a “scout mindset”.12 Thus, if we want to reduce suffering and do our best to help animals, we need to constantly ask ourselves if we are favoring evidence that supports our own beliefs or if we are open to search and analyze data that suggests new ways to be as effective as we can.

Further readings

Festinger, L.; Riecken, H.W. & Schachter, S. (1956) When prophecy fails: A social and psychological study of a modern group that predicted the destruction of the world, Minneapolis: University of Minnesota Press.

Georgesen, J. C. & Solano, C. H (1999) “The effects of motivation on narrative content and structure”, Journal of Language and Social Psychology, 18, pp. 175-194 [accessed on 30 June 2017].

Haidt, J. (2012) The righteous mind: Why good people are divided by politics and religion, New York: Pantheon.

Lodge, M. & Taber, C. (2000) “Three steps toward a theory of motivated political reasoning”, in Lupia, A.; McCubbins, M. & Popkin, S. (eds.) Elements of reason: Cognition, choice, and the bounds of rationality, Cambridge: Cambridge University Press, pp. 183-213.

Mercier, H. & Sperber, D. (2011) “Why do humans reason? Arguments for an argumentative theory”, Behavioral and Brain Sciences, 34, pp. 57-111 [accessed on 25 October 2017].

Nir, L. (2011) “Motivated reasoning and public opinion perception”, Public Opinion Quarterly, 75, pp. 504.

Redlawsk, D (2002) “Hot cognition or cool consideration”, The Journal of Politics, 64, pp. 1021-1044.

Westen, D.; Blagov, P. S.; Harenski, K.; Kilts, C. & Hamann, S. (2006) “Neural bases of motivated reasoning: An fMRI study of emotional constraints on partisan political judgment in the 2004 U.S. Presidential Election”, Journal of Cognitive Neuroscience, 18, pp. 1947-1958.


1 Kunda, Z. (1990) “The case for motivated reasoning”, Psychological Bulletin, 108, pp. 480-498.

2 Damasio, A. R. (1994) “Descartes’ error and the future of human life”, Scientific American, 271 (4), pp. 144-145. Munro, G.D. & Ditto, P. H. (1997) “Biased assimilation, attitude polarization, and affect in reactions to stereotype-relevant scientific information”, Personality and Social Psychology Bulletin, 23, pp. 636-653 [accessed on 7 July 2017].

3 Bargh, J. A. & Chartrand, T. L. (1999) “The unbearable automaticity of being”, American Psychologist, 54, pp. 462-479.

4 Moskowitz, G. B.; Skurnik, I. & Galinsky, A. D. (1999) “The history of dual process notions, and the future of pre-conscious control” in Chaiken, S. & Trope, Y. (eds.) Dual process theories in social psychology, New York: Guilford, pp. 12-36.

5 Sanitioso, R.; Kunda, Z. & Fong, G. T. (1990) “Motivated person perception: Justifying desired conclusions”, Journal of Personality and Social Psychology, 59, pp. 229-241.

6 Loughnan, S.; Bastian, B. & Haslam, N. (2014) “The psychology of eating animals”, Current Directions in Psychological Science, 23, pp. 104-108.

7 Kuhn, D. (1989) “Children and adults as intuitive scientists”, Psychological Review, 96, pp. 674-689. Lord, C. G.; Ross, L., & Lepper, M. R. (1979) “Biased assimilation and attitude polarization: The effects of prior theories on subsequently considered evidence”, Journal of Personality & Social Psychology, 37, pp. 2098-2109.

8 Joy, M. (2010) Why we love dogs, eat pigs, and wear cows: An introduction to carnism, San Francisco: Conari.

9 Kunda, Z. (1987) “Motivation and inference: Self-serving generation and evaluation of evidence”, Journal of Personality and Social Psychology, 53, pp. 636-647. Kunda, Z. & Sanitioso, R. (1989) “Motivated changes in the self-concept”, Journal of Experimental Social Psychology, 25, pp. 272-285. Kunda, Z. (1990) “The case for motivated reasoning”, Psychological Bulletin, 108, pp. 480-498.

10 Haidt, J. (2001) “The emotional dog and its rational tail: A social intuitionist approach to moral judgment”, Psychological Review, 108, pp. 814-834.

11 Ibid.

12 Galef, J. (2016) “Why you think you’re right — even if you’re wrong”, TED, February [accessed on 25 June 2017].

Animal Ethics in other languages