Prof. dr. Jan-Willem van Prooijen

Endowed Professor of Radicalization, Extremism, and Conspiracy Thinking

Welcome!

Prof. dr. Jan-Willem van Prooijen is a behavioral scientist who received his PhD from Leiden University in 2002, and currently holds positions in Psychology and Criminology. He works as Associate Professor of Social Psychology, and Program Director of the Psychology Bachelor, at VU Amsterdam; he is Senior Researcher at the Netherlands Institute for the Study of Crime and Law Enforcement (NSCR); and, he is Endowed Professor of Radicalization, Extremism, and Conspiracy thinking at the Department of Criminal Law and Criminology at Maastricht University. Prof. van Prooijen is interested in the dark side of human beings, particularly in the context of politics, law, and society. His research has three main thematic pillars: (1) conspiracy theories, (2) unethical behavior, and (3) radical ideologies. More details of Prof. van Prooijen’s research on these issues can be found under “research”. Prof. van Prooijen published his work in journals such as Perspectives on Psychological Science, Journal of Personality and Social Psychology, and Personality and Social Psychology Bulletin, and published various books including The Psychology of Conspiracy Theories (Routledge, 2018), The Moral Punishment Instinct (Oxford University Press, 2018), and HOAX (A. W. Bruna, 2024). He received research funding from various sources, and was in 2006 awarded the Early Career Contribution Award by the International Society for Justice Research (ISJR). He has been Associate Editor for Personality and Social Psychology Bulletin, European Journal of Social Psychology and Social Justice Research, and has been on the Editorial Board of various prestigious journals, including JPSP-IRGP and Psychological Science. He was president of ISJR from 2016 to 2018, and regularly appears in the Dutch and International media.

What’s new?

New Books and Special Issue:

Van Prooijen, J.-W. (2024). Hoax: Waarom mensen in complottheorieën geloven. Amsterdam: A. W. Bruna.

Wagner, W., Durmuşoğlu, L., Holá, B., Kroeze, R., Van Prooijen, J.-W., & Werner, W. (Eds.) (2024). Punishment in international society: Norms, justice, and punitive practices. New York, NY: Oxford University Press.

Van Prooijen, J.-W., & Imhoff, R. (2023). Conspiracy theories. Current Opinion in Psychology (Special Issue). Check it out HERE

Recent publications:

Papaioannou, K., Pantazi, M., & Van Prooijen, J.-W. (in press). Rejection of the status quo: Conspiracy theories and preference for alternative political systems. British Journal of Social Psychology.

Van Prooijen, J.-W. (in press). Group-oriented motivations underlying conspiracy theories. Group Processes & Intergroup Relations.

Wang, H., Van Prooijen, J.-W., & Van Lange, P. A. M. (in press). How perceived coercion polarizes unvaccinated people: The mediating role of conspiracy beliefs. Journal of Health Psychology.

Dong, M., Van Prooijen, J.-W., & Van Lange, P. A. M. (in press). Status cues and moral judgment: Formal attire induces moral favoritism but not for hypocrites. Current Psychology.

Schlette, A., Van Prooijen, J.-W., Blokland, A., & Thijs, F. (in press). Information, identity, and action: The messages of the Dutch anti-vaccination community on Telegram. New Media & Society.

Schlette, A., Van Prooijen, J.-W., Blokland, A., & Thijs, F. (in press). The online structure and development of posting behavior in Dutch anti-vaccination groups on Telegram. New Media & Society.

Zhao, Q., Ma, R., Liu, Z., Wang, T., Sun, X., Van Prooijen, J.-W., Dong, M., & Yuan, Y. (2024). Why do we never have enough time? Economic inequality fuels the perception of time poverty by aggravating status anxiety. British Journal of Social Psychology, 63, 614-636.

Zeng, Z.-X., Tian, C.-Y., Mao, J.-Y., van Prooijen, J.-W., Zhang, Y., Yang, S.-L., Xie, X.-N., & Guo, Y.-Y. (2024). How does economic inequality shape conspiracy theories? Empirical evidence from China. British Journal of Social Psychology, 63, 477-498.

Van Prooijen, J.-W., & Böhm, N. (2024). Do conspiracy theories shape or rationalize vaccination hesitancy over time? Social Psychological and Personality Science, 15, 421-429.

Durmuşoğlu, L., Van Prooijen, J.-W., Wagner, W. (2024). Punishment beyond borders: Attitudes towards punishment in interpersonal and international contexts. Chapter in W. Wagner, L. Durmuşoğlu, B. Holá, R. Kroeze, J.-W. van Prooijen, & W. Werner (Eds.), Punishment in international society: Norms, justice, and punitive practices. New York, NY: Oxford University Press.

Wagner, W., Durmuşoğlu, L., Holá, B., Kroeze, R., Van Prooijen, J.-W., & Werner, W. (2024). Norm violations and punishment beyond the nation-state: Normative orders, authority, and conflict in international society. Chapter in W. Wagner, L. Durmuşoğlu, B. Holá, R. Kroeze, J.-W. van Prooijen, & W. Werner (Eds.), Punishment in international society: Norms, justice, and punitive practices. New York, NY: Oxford University Press.

Van Sintemaartensdijk, I., Van Gelder, J.-L., Van Prooijen, J.-W., Nee, C., Otte, M., & Van Lange, P. A. M. (2024). Assessing the deterrent effect of symbolic guardianship through neighbourhood watch signs and police signs: A virtual reality study. Psychology, Crime, and Law, 30, 1-21.

Fousiani, K., & Van Prooijen, J.-W. (2023). Instrumental goals shape EU citizens’ attitudes to the Russia-Ukraine war over time. International Journal of Psychology, 58, 563-573.

Van Prooijen, J.-W., Amodio, D. M., Boot, A., Eerland, A., Etienne, T., Krouwel, A. P. M., Onderco, M., Verkoeijen, P., & Zwaan, R. A. (2023). A longitudinal analysis of conspiracy beliefs and Covid-19 health responses. Psychological Medicine, 53, 5709-5716.

 Papaioannou, K., Pantazi, M., & Van Prooijen, J.-W. (2023). Is democracy under threat? Why belief in conspiracy theories predicts autocratic attitudes. European Journal of Social Psychology, 53, 846-856.

Bertin, P., Delouvée, S., McColl, K., & Van Prooijen, J.-W. (2023). Rage against the machine: Investigating conspiracy theories about the Video Assistant Referee on Twitter during the 2018 FIFA World Cup. Sports Management Review, 4, 495-516.

 Azevedo, F., Pavlović, T., Rêgo, G. G. d., Ay, F. C., Gjoneska, B., Etienne, T., … Sampaio, W. M. (2023). Social and moral psychology of COVID-19 across 69 countries. Nature Scientific Data, 10, 272.

 Martinez, C. A., Van Prooijen, J.-W., & Van Lange, P. A. M. (2023). The hateful people: Populist attitudes predict interpersonal and intergroup hate. Social Psychological and Personality Science, 14, 698-707.

 Fousiani, K., & Van Prooijen, J.-W. (2023). Motives for punishing powerful vs. powerless offenders: The mediating role of demonization. Victims & Offenders, 18, 1070-1092.

 Van Prooijen, J.-W., Wahring, I., Mausolf, L., Mulas, N., & Shwan, S. (2023). Just dead, not alive: Reconsidering belief in contradictory conspiracy theories. Psychological Science, 34, 670-682.

 Fousiani, K., & Van Prooijen, J.-W. (2023). The effects of culture on active and passive reactions to financial offenders: The moderating role of type of harm. Victims & Offenders, 18, 961-987.

Van Prooijen, J.-W. (2023). Complottheorieën als vermoeden van een onrechtvaardige overheid. In A. van Ravenzwaaij & O. Fajgenblat (Red.). Reflecteren op rechtvaardigheid: Over de betekenis van rechtvaardigheid in de relatie tussen overheid, ambtenaar en samenleving. (pp. 143-155). Den Haag: Boombestuurskunde.

Van Prooijen, J.-W., Etienne, T., Kutiyski, T., & Krouwel, A. P. M. (2023). Conspiracy beliefs prospectively predict health behavior and well-being during a pandemic. Psychological Medicine, 53, 2514-2521.

 Wang, H., & Van Prooijen, J.-W. (2023). Stolen elections: How conspiracy beliefs during the 2020 American presidential elections changed over time. Applied Cognitive Psychology, 37, 277-289.

 Van Prooijen, J.-W. (2023). Feelings of insecurity as a driver of anti-establishment sentiments. In J. P. Forgas, W. D. Crano, & K. Fiedler (Eds.), The psychology of insecurity: Seeking certainty where none can be found (pp. 368-388). Oxon, UK: Routledge.

 Spadaro, G., Molho, C., Van Prooijen, J.-W., Romano, A., Mosso, C. O., & Van Lange, P. A. M. (2023). Corrupt third-parties undermine trust and prosocial behavior between people. Nature Human Behaviour, 7, 46-54.

Dong, M., Kupfer, T. R., Yuan, S., & Van Prooijen, J.-W. (2023). Being good to look good: Self-reported moral character predicts moral double standards among reputation-seeking individuals. British Journal of Psychology, 114, 224-261.

Papaioannou, K., Pantazi, M., & Van Prooijen, J.-W. (2023). Unravelling the relationship between populism and belief in conspiracy theories: The role of cynicism, powerlessness, and zero-sum thinking. British Journal of Psychology, 114, 159-175.

Other news from Prof. van Prooijen's research group:

In September 2023, Selen Goksal has started with her PhD project on the psychological basis of ideological punishment. The project will take place at the VU’s department of Experimental and Applied Psychology, and she is being supervised by Prof. van Prooijen and Dr. Giuliana Spadaro.

In April 2023, Astrid Bastiaens has started with her PhD project on leaking behavior among terrorist suspects. The project will take place at Maastricht university, and she is being supervised by Prof. van Prooijen and Prof. Jelicic.