Why do we overestimate agreement?

The 

False Consensus Effect

, explained.
Bias

What is the False Consensus Effect?

The false consensus effect describes how individuals frequently overestimate how much others share their beliefs, values, and behaviors. This implies that people often project their personal attitudes and ideas onto others, assuming they are more common or widespread than they actually are.2

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Where this bias occurs

Imagine you are a fitness enthusiast who works out daily and maintains a strict, healthy diet. Over time, you've noticed that you feel better and more energetic. You start believing everyone should adopt a similar lifestyle to reap the same benefits. You assume that most people are interested in regular exercise and healthy eating, just like you. 

So, at your next family gathering, you decide to open up the topic and discuss your newfound discovery. But, surprisingly, not everyone is as enthusiastic about it as you are. Some family members prefer a more relaxed way of life, while others have different hobbies and interests. Shockingly, they don't share the same commitment to fitness and nutrition. You are taken aback to discover that your perception about the general consensus on fitness and health was incorrect.

This personal anecdote exemplifies the false consensus effect in action. The bias led you to mistakenly believe that your dream lifestyle of squats and smoothies would be accepted by all. But instead, it highlights how easy it is to project our own behaviors onto society at large.

Related Biases

Sources

  1. Ross, L., Greene, D., & House, P. (1977). The false consensus effect: An egocentric bias in social perception and attribution processes. Journal of Experimental Social Psychology, 13(3), 279–301. https://doi.org/10.1016/0022-1031(77)90049-X
  2. Good, H. (2023, February 7). What is the false consensus effect. Cognitive Biases. Retrieved from https://dovetail.com/research/false-consensus-effect/
  3. Tversky, A., & Kahneman, D. (1974). Judgment under Uncertainty: Heuristics and Biases. Science, New Series, 185(4157), 1124-1131.
  4. Festinger, L. (1954). A Theory of Social Comparison Processes. Sage Journals, 7(2). https://doi.org/10.1177/001872675400700202 
  5. Steele, C. M. (2008). The Psychology of Self-Affirmation: Sustaining the Integrity of the Self. Science Direct.  https://doi.org/10.1016/S0065-2601(08)60229-4 
  6. Moore, P. (2014, August 22). Poll Results: Ice Bucket Challenge. YouGov/US. https://today.yougov.com/entertainment/articles/10183-poll-results-ice-bucket-challenge 
  7. Luzsa, R., & Mayr, S. (2021). False consensus in the echo chamber: Exposure to favorably biased social media news feeds leads to increased perception of public support for own opinions. Cyberpsychology: Journal of Psychosocial Research on Cyberspace, 15(1), Article 3. https://doi.org/10.5817/CP2021-1-3
  8. Dastin, J. (2018, October 10). Insight - Amazon scraps secret AI recruiting tool that showed bias against women. Reuters. Retrieved September 18, 2024, from https://www.reuters.com/article/world/insight-amazon-scraps-secret-ai-recruiting-tool-that-showed-bias-against-women-idUSKCN1MK0AG/
  9. Choi, I., & Cha, O. (2019). Cross-Cultural Examination of the False Consensus Effect. Frontiers in Psychology, 10, 428636. https://doi.org/10.3389/fpsyg.2019.02747
  10. Kahneman, D., Sibony, O., & Sunstein, C. R. (2021). Noise. William Collins.

About the Authors

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Dan Pilat

Dan is a Co-Founder and Managing Director at The Decision Lab. He is a bestselling author of Intention - a book he wrote with Wiley on the mindful application of behavioral science in organizations. Dan has a background in organizational decision making, with a BComm in Decision & Information Systems from McGill University. He has worked on enterprise-level behavioral architecture at TD Securities and BMO Capital Markets, where he advised management on the implementation of systems processing billions of dollars per week. Driven by an appetite for the latest in technology, Dan created a course on business intelligence and lectured at McGill University, and has applied behavioral science to topics such as augmented and virtual reality.

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Dr. Sekoul Krastev

Sekoul is a Co-Founder and Managing Director at The Decision Lab. He is a bestselling author of Intention - a book he wrote with Wiley on the mindful application of behavioral science in organizations. A decision scientist with a PhD in Decision Neuroscience from McGill University, Sekoul's work has been featured in peer-reviewed journals and has been presented at conferences around the world. Sekoul previously advised management on innovation and engagement strategy at The Boston Consulting Group as well as on online media strategy at Google. He has a deep interest in the applications of behavioral science to new technology and has published on these topics in places such as the Huffington Post and Strategy & Business.

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